Upgrading brake on a 96 Dodge 2500 to 3500

Tiny
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  • 1996 DODGE RAM
  • 8.0L
  • V10
  • 2WD
  • AUTOMATIC
  • 72,000 MILES
I am thinking of upgrading my brakes on my dodge 2500 to 3500 brakes. I know I would or most likely need to change the calipers and rotors on the front along with the master cylinder. Would the spindles need to be changed out and/or any other suspension parts. On the rear I don't know if there was a 96 3500 that had rear disk brake and if so would a 3500 disk brakes and rotors go on my rear brake drum axle? Would I need to change out the rear end housing?

Please don't answer if you do not know for sure and know what all needs to be done if it can be done. There will be no donation for guessing.
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Tuesday, June 30th, 2015 AT 3:20 PM

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Tiny
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I need to mention the upgrade is not a dually
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Wednesday, July 1st, 2015 AT 5:51 AM
Tiny
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I see you've been waiting two days for a reply. I read it earlier but I can't answer some of your questions. What I CAN suggest is the brakes are already strong enough to lock up the wheels, so going to anything larger isn't going to give you more stopping power, including when pulling a trailer. What you will get is larger rotors will build up heat at a slower rate, and that leads me to an important point you should be aware of. A few decades ago, I had a car with a rotor I had cut a total of 1/8" under the legal limit, and under the other rotor. It never caused a problem, however, ...

On the newer vehicles, trucks in particular, two different size rotors will cause a horrendous brake pull when they get hot. Dodge had a 32 page service bulletin about this, and in fact I was involved with three of those trucks. One was a truck the owner had just bought. The previous owner sold it for this elusive problem shortly after having a brake job done. The other two were lemon law buybacks that would have been solved if the mechanics had just followed the service bulletin. Those rotors were about 1 1/4" thick, but on one truck, one rotor was.020" thinner than the other one. On the second truck, one was.007" thinner! That's the thickness of two sheets of paper, but it caused a very hard brake pull after about a half dozen fairly hard stops. The customer's truck got two new rotors. On both lemon law trucks, I cut the thinner rotors to true them up, then cut the thicker ones to match within.001". It's important to note the speed of cut has to be identical too. That results in the same number of grooves, and therefore the same pad-to-rotor contact area. This brake pull never shows up right away or during normal braking. It results from repeated hard stops such as when coming down a steep hill. On the trucks I was involved with, all of them stopped perfectly straight for seven hard stops on the same hill I used, then they pulled real hard on the eighth stop just a few seconds later. The cause was a change in the coefficient of friction that took place at the higher temperature, and since the rotors were different thicknesses, the thinner one heated up faster. By the way, that 32-page service bulletin had us checking everything under the sun from the alignment to replaced suspension parts, then they finally presented the solution on the last page or two.

The next thing to keep in mind is every vehicle has a proportioning valve in the brake hydraulic system that everyone forgets about. That limits the amount of fluid pressure to the rear brakes to reduce rear-wheel lockup. Most trucks and minivans have a height-sensing proportioning valve at the rear axle because they can have such a wide variation in loading. When cars are lowered or trucks are raised, that changes the amount of weight transfer to the front, and that changes the calibration needed in that valve. Lawyers and insurance investigators know all about altered ride height and they will use it to convince a jury that you were partly at fault for the crash when the other guy ran the red light because you were less able to avoid it, and they will be right.

You could run into the same problem with altered brakes. I'm less of an expert on potential lawsuits related to altered brakes, so the best I can share is you will no longer have the carefully-designed-in front-to-rear braking balance. A skidding tire has no traction, so when one does start to skid, you have to let off the brake pedal a little to keep it in traction. Three tires were not yet stopping to their fullest potential, but you let off the brakes a little. That is proof the stopping distance was longer than it could have been.

The first issue I mentioned was heat buildup from pulling a trailer. The second one has to do with the 3500s experiencing rapid front brake pad wear. Front pads should wear out about twice as fast as the rear shoes or pads. We were told that if there was a 3500 that was experiencing rapid front pad wear, we could increase the rear wheel cylinder diameter by 1/16". If there was a truck that was constantly heavily-loaded, we could increase the diameter by 1/8", but there was a hitch. Chrysler never used that size so the replacements had to come from a GM dealer. Those were factory-approved modifications to solve a problem under certain conditions, so there was no threat of a future lawsuit. The original wheel cylinder diameter was the result of those calculations that led to balanced front-to-rear braking.

Some people will tell you to switch from drum rear brakes to disc, but again, that isn't going to gain you any stopping power. On trucks and most older cars, drum brakes are of the "duo-servo" design which means the front shoe's only job is to apply pressure to the bottom of the rear shoe. This is referred to as a "self-energizing" brake and it's real effective. Drum brakes worked great for stopping heavy cars and trucks. The drawbacks are it's harder for heat to escape and they they take a long time to recover after driving through deep water. Disc brake pads are always in contact with the rotors, so they squeegee off water, and since they're in the open, heat dissipates better. Their drawback is they are not self-energizing so a lot of pedal pressure is needed. This is where a power booster becomes necessary. The main reason you'll find disc brakes on the rear is calipers present less moving mass compared to shoes, so they respond better to the pulsing action of an anti-lock brake system.

As for the parts interchangeability you're asking about, I can offer two suggestions. First, I use the Rock Auto web site for reference quite a bit. You can look up parts and compare the part numbers from various manufacturers for both applications. If the part numbers are the same, obviously that part fits both trucks, but when they're different, you don't know why. One could use a ball joint with a larger tapered stud, or it could simply have an additional threaded hole for a brake hose bracket. The next is to visit a Dodge dealer's parts department to see if they offer an off-road upgrade kit. They will also be able to tell you which parts were available as part of an optional brake system. This is where the off-road modification kits are nice. Those will include the proportioning valve, calipers, and wheel cylinders as a matched set, and they will include a master cylinder or specify if a different one is needed. Normally the master cylinder's bore size is a trade-off between pedal pressure and pedal travel. A larger cylinder diameter will move more brake fluid with less pedal travel, but you'll need much more foot pressure to stop the truck.

You DO have to change the master cylinder when changing from drum to rear disc brakes. Drum systems have a residual check valve in the port in the master cylinder. That keeps about ten pounds of fluid pressure on the lip seals in the wheel cylinders at all times. Ten pounds of fluid pressure on a caliper would keep it applied and dragging.

My daily driver is an old rusty trusty '88 Grand Caravan with the optional heavy duty brakes. I use it to pull a tandem axle enclosed trailer that's bigger and heavier than the van to the nation's second largest old car show swap meet, (next week), and I have never even bothered to hook up the trailer brakes. I can't hit 70 mph due to the wind resistance, but stopping has never been a problem. I can't imagine your truck having a problem pulling my trailer. What kind of braking problem are you trying to overcome?
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Thursday, July 2nd, 2015 AT 5:12 PM
Tiny
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I have been pulling a travel trailer and the combination of both load with the pickup with around another 500 lbs added to it both are 14600 lbs and the pickup alone is 6200 lbs with just me in it. Yes I can lock the brakes up when the pickup is without the trailer but with the weight distribution when hooked up to the trailer there is no locking up the brakes because there is more weight not only put on the rear but the frond wheels also. The recommended setup is to have the front and rear ends of the pickup to settle down the same when the weight distribution is set properly. I got it as close as I can with the pickup front settled down 1/2" and the rear 3/4" with the trailer level front to rear. I have had two hard stops and braking as hard as I could (yes I have a lot of leg strength) and wasn't able to lock the wheels up. Before that hard braking I did change out all the brake fluid to DOT 4 (475 deg.) Brake fluid for the higher temperature fluid because I knew we would be going into mountains with down grades of up to 7% for long distances. Bleeding the system and adding new fluid get rid of any moisture that the fluid would have collected over the years thus lowing the boiling temperature of the fluid. I changed the front pad to the best I could get that give better braking at high temperatures also. Before I changed the front pads the truck was pulling to the right and had a chatter when braking. When I checked the pads on both front wheels the right pad had worn down more than the left and to the point there was no taper left on the pad, thus more braking power and no taper to get away from the chatter. After the hard braking I thought there might be some air in the system so I bled the master cylinder and all corners again. I didn't notice any air. While on the trip I seen a 3500 like mine without the extended cab 2wd but diesel and not a dually, I didn't know there was such an animal. When I got home I checked with the auto parts store if there was a difference in the brakes and calipers and they were bigger. After bleeding the system with the pickup by itself I don't notice any difference in braking and haven't tried heavy braking with the trailer yet. This is why I was looking into upgrading the braking system.

The travel trailer has electric brakes also that I setup and use.

I wonder with the new pads if they have to really heat up more so that standard pads to get to full braking power. Or maybe I have a faulty master cylinder (?). When I bled the system again and as always I bleed the right rear wheel first, then the left rear, then the right front and last the left front.

For years I had drove a company F350 of different year and those brakes didn't need much peddle pressure to lock up the wheels.
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Thursday, July 2nd, 2015 AT 9:35 PM
Tiny
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I have a feeling something else is going on here. Do you have rear-wheel anti-lock brakes?

I have a friend with a body shop who specializes in rebuilding one and two-year-old smashed Dodge trucks. Last year he got a 2500 MegaCab from Iowa. We went to Detroit to a salvage yard that buys a real lot of stuff directly from Chrysler. He got a never-installed frame, and an 8' dually box that was used in experiments with running diesels on compressed natural gas. He cut the truck's frame and the new one and used 60 percent of each to turn this truck into a dually diesel MegaCab with 8' box. We know you're not supposed to weld on these, but this was for himself. When he comes to plow snow from my driveway, I wave to him, then have to wait a while for the tail lights to show up!

The point of this sad story is this is still a 2500 but with the dually rear axle, that if I remember right, was from a 3500. The brakes were the same as on the single-wheel axle we removed. He used this truck to move his sister back from Texas to Wisconsin last summer. That was with a 32' goose neck heavy equipment trailer that he built an 8'-high box around, then filled it with her crap, ... Ah, ... Stuff! Halfway home all eight studs broke on one of the trailer's four pairs of wheels. A company that repairs semi trucks and trailers on the road came out, then they had to go back for more equipment because they couldn't lift the trailer with what they use for semi trailers. Now THAT'S overloaded, but he never had a problem stopping that load. Remember, this is a 2500 with standard rear leaf springs, but he did add air springs. He has also hauled those huge round bales of hay you see in fields sometimes, for nearby farmers. He once hauled 40 of them on that trailer, and they say those are 1,000 pounds each. The farmer's kid had trouble with his Ford trying to haul 15 of them. This tells me the 2500s don't suffer from weak brakes, and is why I think something else is going on with yours.

Now, that's not to say there isn't a heavy duty optional brake system with beefier parts. That's why I'm in favor of you visiting the dealer's parts department. At the Dodge dealership where I worked, the people in that department were real happy to look stuff up for people as long as you would give them a day to do it when things were slow. They can also do research through Chrysler's web site for dealers.

One more thing you might consider is asking at the dealership where they send their mechanics for live training. We used to have a training center near Milwaukee, and the instructors used my Auto Shop and those of two other community colleges as remote training sites. Those instructors are extremely knowledgeable about options, modifications, and especially finding solutions to what the engineers and designers messed up. They are usually quite willing to talk with owners as long as it doesn't interfere with their class schedule. They don't have classes every day. In fact, they may go for weeks without seeing students. They use their time researching problems and coming up with fixes for them.

This brings me back to the original suspicion that something else is going on. The first thing I'd check is if the pads are glazed. When the rotors just slide off once the calipers are off, I take a light cut on the brake lathe, then let that roughness chew off the glaze. For "captive" rotors that require removing the wheel bearings, I just use course sandpaper and scrape the glazing off by running the vehicle in gear on a hoist until I burn my fingers!

Obviously if you have four-wheel anti-lock brakes, the wheels had better not lock up. If you don't, you almost certainly will have rear-wheel anti-lock, so it's unlikely you'll get the rear tires to skid.

I hope that gives you something to start with. I'm racing a dying laptop battery so I have to call it quits for tonight, but I'm going to keep thinking on this. I'll check with my friend too and see if there was anything else he modified with his brake system.
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Thursday, July 2nd, 2015 AT 11:21 PM
Tiny
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Thank you for your replies, you have gave me a lot to think about and research. I knew there was a science to brake system setups and wasn't going to do anything until I understood it all and had a workable rework/upgrade. As for my pickup it is 2wd with anti-lock and the anti-lock has worked in the past on snow and ice, the brakes pumped. But on those hard stops with the trailer there was no pumping. I don't think the front pads are glazed but will check them. The rear shoes could be glazed and never replaced those shoes while the front pads have been replace the third time in 6000 plus miles. The pad were never totally worn out the first time but just worn down to where I thought it would be good to change them and that second time the right was worn more than the left that caused a pull to the right. For glazing, the rotors didn't look glazed and they have never been turned. Then have always been smooth when I changed out the pads.

A little history on the pickup. I bought it used in 02 with 27000 miles and the previous owner did pull a 5th wheel travel trailer. I did see the trailer he was pulling and I think my trailer is heaver than what he was pulling. It was in 2013 when I retired and bought the 32 ft Avion travel trailer and started pulling any kind of trailer with the pickup. On 6/02/13 after our first vacation with the trailer the pickup only had 57000 miles on it and now only 72000 miles. Yeah, it has spent most of it's life in the garage.

As of now what you have said I should have the rotors turned just to make sure they aren't glazed and have matching surfaces and thicknesses. The rotors don't show much wear at all but could need to be smoothed up. The pickup doesn't pull to the right or left as of now but with the advice turning the rotors I will make sure they end up with the same thickness rotors and turned at the same speed. If I turn the rotors I should change the pads also I am thinking, I will check the rear drums for glazing. If they look to be glazed or the shoes worn down to where I think they need to be replaced I will turn the drums and replace the shoes. The last time I checked the shoes on the rear was around 40 some thousand miles and with on harder braking I had done I don't think they are worn much but will check it out.

If I turn the rotors do you think O'Reilly's or NAPA (local shops that turn drums and rotors) would be able to turn them at the same speed as the amount of speed the cutting bit moves from the outside to the inside when cutting? I am thinking the rotation speed and movement of the bit is all a preset speed but not sure. I never thought about the difference of thickness and turning speed before but glad to know now and what to look for if there is a pull to the right or left after turning the rotors.

You keep this up I am going to have to give a donation. A lot of very good advice that I didn't know.
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Friday, July 3rd, 2015 AT 6:23 AM
Tiny
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As of the last stop or slow down on this year's vacation to Yosemite we were going down a down grade of 8% for 6 miles, that was spooky. I end up in first gear and still having to apply brakes to slow down so as not to over speed the truck and trailer or the engine. About a mile before we got to the bottom I could smell the brakes heating up so I pulled over on a turnout to cool them off. When we got stopped smoke was rolling out from the front brakes, the rear brakes/rims were hot along with the trailer brakes/rims. I wasn't riding the brake but would apply brakes to slow down and then let the truck speed up before applying brakes again. When I got home I repacked the front bearing.
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Friday, July 3rd, 2015 AT 6:46 AM
Tiny
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Even with that slow down and stop there was no pulling to the right or left that I remember and sure no hard pull to the right or left. After that there was no hard stop either to try to lock up the brakes. The two times the brakes should have locked up was getting stopped at a traffic light and I was braking as hard as I could. Be sure to read my other 2 replies above. I have been adding more as I think if it.
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Friday, July 3rd, 2015 AT 6:57 AM
Tiny
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Well, we know if that's four-wheel anti-lock brakes, the wheels won't lock up, but that's actually a good thing for stopping. I have a '93 Dynasty with the Bendix-10 ABS system. That will just about tear the seat belts off their hinges! Remember my comment about a skidding tire has no traction, and to get the traction back, you have to let up on the brake pedal even though the other three brakes weren't stopping to their maximum potential? Well, 4-wheel ABS takes care of that. The system looks at the four wheel speeds, then disregards the fastest wheel. Of the other three, it looks for the one spinning the slowest, blocks any additional fluid flow to it, even if you push harder on the brake pedal, then, if it still isn't speeding up, it bleeds off some fluid pressure. Once it's back up to speed, it opens a third valve to reapply fluid pressure. It does that "block, bleed, apply" between 15 and 30 times per second for each wheel. That means every brake is stopping at its maximum potential.

GM used a similar Bendix-9 on the Caprice Classic. The difference is they modulated the two rear wheels together, so it was a "three-channel" system instead of a four-channel system. There had to be some other differences too because I drove one after aligning it, and the system did exactly what it was designed to do, ... Allow you to maintain steering control. As a friend who is a county deputy put it, "if you slam on the brakes, you go and go and go, and they find you in the next county! I was my dealer's suspension and alignment specialist all through the '90s so I drove a lot of Chrysler products, and I never found one to have such miserable brakes. Remember, the purpose of anti-lock brakes is to prevent skidding tires so the front ones can be steered, and so the rear ones don't pass up the front of the truck. The shorter stopping distances is an unexpected byproduct but Chrysler's systems have been much more effective at that than systems on most other vehicles.

My reason for sharing all of this wondrous information is to point out that you have brakes that are already strong enough to lock up the wheels. They just aren't doing that by design thanks to the ABS system. So stopping power isn't what you need more of. What you need is less heat buildup. Even the trailer brakes were hot, so you know they were all really working.

I'd still talk with the guys at the dealer's parts department first, but then you might look at aftermarket parts. I would be willing to bet you are not the first person to have a truck with hot brakes, so there is likely to be someone who developed a solution. I did a search last night for "Dodge truck brake upgrade". A number of interesting things came up, but you have to understand that all manufacturers of brake linings have to design their parts so the same front-to-rear balance is maintained. If you only replace the front pads, those new linings have to work with the original rear shoes. One can't have a higher coefficient of friction, but I don't know how closely they have to watch that at abnormally-high temperatures.

There are different types of brake fade and you may be experiencing one of them. Really hot linings give off a gas that gets between the rotors and pads and acts like little ball bearings. No amount of additional pedal pressure will overcome that. This again is why you should look at reducing heat buildup, not increasing stopping power. I realize the two are related, but solutions come from different directions.

What about a Jake Brake? I don't know much about them or if they're even an option with a gas engine.
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Friday, July 3rd, 2015 AT 11:38 PM
Tiny
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I know I don't have 4 wheel ABS because there are no sensors on the front wheels. It must be on the rear only. The only time I remember the ABS kicking in by the pumping of the brakes was on ice and snow (maybe) but that was a long time ago because I don't take it out when it is slick. Even with the positive track rear end and very good all season tires there is too much torque from the engine to do much in the way of starting off and then stopping. If I have to get out I take the wife's mountain goat Subaru all wheel drive. It can go places that pickup wouldn't even think of going. The pickup was bought for towing a travel trailer and hauling items when needed. Before I put a camper shell on it, it would bark the tires when shifting into second and really not pushing hard on the foot feed. When it is slick you can't feather the throttle enough to keep from spinning the rear tires and if you are going up hill you are done.

I have heard about losing brakes when things get really heated up and that is why I pulled off to the side in Yosemite before that could happened.

I done a quick search for a gas jake brake and the only one I found was

Decelomatic Corporation
Louis King, Owner
4837 E. Indian School Rd.
Phoenix, AZ 85018
(602) 956-8200

This is what else I found about a gas jake brake

Because of the low back pressure limits of gasoline engines, the performance of a gasoline exhaust brake would not be substantial. Because the air intake in a gasoline engine is throttled and the compression ratio is much lower than in a diesel, the performance of a gasoline engine brake would also be insignificant.

And this

So. This weekend I saw an EB manufacturer at the Hershey show and I asked the sales rep. He had a pretty clear answer - it has nothing to do with intake restriction or compression ratios. The limiting factor is the strength of the valve springs. The diesels have bigger springs on the valves and can take the higher exhaust backpressure without floating open, gas engines have springs roughly 1/3 the strength and can only take 1/3 the backpressure before they float. Backpressure is directly proportional to EB braking power and the lower acceptable backpressure on the gasser's means that EB's are really not effective enough to make them worth added cost/complexity. I had wondered about this and now (I think) I understand.

One other person talked about a possible lifter jack with a jake brake on a gasser and that wouldn't be a good thing.
I don't know what is all involved with a lifter jack but it doesn't sound good.

Another thing I thought about is the exhaust headers/manifold gaskets. I don't think the whole setup is designed for much back pressure and would blow a gasket rather easily.

I did see one person talk about a exhaust brake on his gasser motor home and loved it. How much it helped he didn't say.

It has been done but is it cost worthy. That is getting in a area that could cause very costly problems due to the limited amount of systems and research out there.

I think I need to look at my brake system again very close and do some testing with what I have to make it the way it should be. I think I should be able to lock up those front tires when towing with the equipment I have but some work done on it.

If you have more to add please do so I really like this research and where it has taken me.
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Saturday, July 4th, 2015 AT 1:31 AM
Tiny
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It never occurred to me that valve float would be an issue, but after thinking about it, I can see where it would be. Regardless, we're getting into an area I am not an expert on. I've never owned a diesel, and when I've gone on out-of-state trips with my friend to fetch trucks and parts, we've never been loaded enough to need the one built into his truck, so I've never driven with one either.

I promised you I was going to consult him for other ideas but I haven't been able to get a hold of him. I'll be seeing him tomorrow on my way to an old car show swap meet. Last year the wireless internet at the show was terrible, so you probably won't hear back from me until next Monday night. Hopefully I'll have some better ideas.
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Tuesday, July 7th, 2015 AT 9:25 PM
Tiny
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Caradiodoc, do you have any more information
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Tuesday, August 4th, 2015 AT 3:02 PM
Tiny
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Nothing of value to report. According to my friend, Jake brakes can be used on gas engines but they aren't nearly as effective. Valve float should not be an issue, because any back-pressure in the exhaust system comes from inside the cylinders. The pistons will just encounter a lot more resistance when it comes to pushing that gas out under pressure. It's true that the valve springs do not need to be nearly as strong as on diesel engines so intake vacuum doesn't pull a valve open, but you also don't have such a high compression ratio either. You still won't build up enough exhaust pressure to push an exhaust valve open. You have to remember, we run into plugged catalytic converters from time to time, and one of the symptoms is an unusually smooth idle, and a steady hiss from the tail pipe. Valve float is not one of the clues.
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Wednesday, August 5th, 2015 AT 9:27 PM
Tiny
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Glad you mentioned plugged catalytic converters and wondered what the symptoms are. I don't think mine (2) are plugged, and only have 72k miles on it. What mileage do you see dual cats plugged on a 96 V10?

I done a check on the difference of 2wd 96 2500 and 3500 size of brake rotors and master cylinders. Rotors are the same diameter but the brake pad area for the 3500 could be wider, but different pads. Maybe the pads are wider and longer on the 3500. The Master cylinders are the same.

I checked out my hard braking at 35 mph with the trailer and I was able to push the peddle to the floor without locking up the brakes but it was hard to do so. But I have a lot of leg strength, when I worked out I could do leg presses of 1200 lbs or more. What I am wondering is the brake fluid is by passing the piston with that much pressure and I need a new master cylinder.
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Wednesday, August 19th, 2015 AT 10:49 AM
Tiny
CARADIODOC
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You're thinking backward about the master cylinder. As you push harder on the brake pedal, the fluid pressure pushes out on the lip seals and makes them seal better. One of the tricks we use is to push lightly on the pedal, and ease up on it momentarily. If the lip seals are worn or torn, the reduced pedal pressure often lets the seals relax and lets fluid bypass one of them. When that happens, the pedal will sink to the floor and the red "Brake" warning light will turn on.
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Wednesday, August 19th, 2015 AT 12:45 PM
Tiny
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I have bled the lines and master cylinder twice to make sure there isn't any air anywhere. The only think I can think of is there's a air pocket somewhere.

I was reading one of the other threads where a expert said when bleeding an brake system with a old master cylinder don't push the peddle to the floor because there is corrosion in the zone where the piston hasn't been and will scar the seals and while under heavy braking the peddle could or would go to floor. I know about seal leaking like you said. I had a Triumph Spitfire that the peddle would go to the floor on real light braking but if you would let off and then hit the peddle a little harder you would have brakes.
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Wednesday, August 19th, 2015 AT 2:44 PM
Tiny
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I have held the brake peddle somewhat hard for a while and the peddle doesn't move, so with that much pressure on the system there isn't any fluid bypassing the piston.
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Wednesday, August 19th, 2015 AT 2:52 PM
Tiny
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I don't think you have a master cylinder problem. If one seal had internal leakage, the red "Brake" warning light would turn on due to unequal pressures in the two hydraulic systems. If both systems were leaking, you would have no brakes at all at some point. From everything you've described, my mind keeps going back to glazed linings.
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Wednesday, August 19th, 2015 AT 3:25 PM
Tiny
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In one of your other thread I read if I was to push lightly on the brake peddle and the peddle keeps moving and finely to the floor master cylinder is bad or the seals. I did this and the peddle went to the floor with light pressure, but it took a while. Another thing, I have ABS on this 96 Dodge 2500 2wd and I read in another thread that on a 95 Dodge Plymouth Voyager a DRB-II SCAN TOOL needed TO BLEED THE MODULATOR. Do I need the tool because one time when I was working on the brakes the master cylinder dripped dry. I looked in my owner's manual and it doesn't say anything about bleeding the brakes.

Would I be able to bleed the modulator if I done your suggestion of slowly pushing in the brake peddle for 20 sec. to allow the air bubbles to float up to the master cylinder and then letting of the brake peddle real fast?

http://www.2carpros.com/questions/plymouth-voyager-1995-plymouth-voyager-brake-pedal-travels-almost-to-floor-b
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Wednesday, August 19th, 2015 AT 3:51 PM
Tiny
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I have a ABS light with first turning on the key but the own's manual doesn't have anything about ABS brakes
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Wednesday, August 19th, 2015 AT 4:07 PM
Tiny
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The reason I know about the '95 minivans is I have one. It does require a scanner to open some of the valves so air can escape. The slow pedal trick won't work on that. As I recall, you have rear-wheel ABS. Those systems don't require separate bleeding. That valve assembly only blocks fluid flow, then allows it. It doesn't have a separate high-pressure system to apply fluid pressure. The RWAL, (rear-wheel anti-lock) valve is normally open, just like a piece of steel brake line, so air will bleed right out.

If your brake pedal is sinking slowly under light foot pressure, then you may indeed have internal leakage. If you have to replace the master cylinder, start with the new one already bench-bled so it's ready to go, loosen the soft metal line nuts at the master cylinder's ports, unbolt the master cylinder from the power booster, then use it as a handle to bend the steel lines up a little. That will prevent the fluid from running out of the tops of those lines.

Remove the lines, then install them on the new master cylinder. Bend the lines back down so you can bolt the master cylinder to the power booster. Snug one of the line nuts. Have a helper slowly push the brake pedal about halfway to the floor and hold it there while you tighten the nut. Release the pedal quickly so the fluid rushing back washes any air bubbles with it into the reservoir. Loosen the nut and do that once more until you don't see any air bubbles coming out. Do the same thing for the second line.

There's no way air can get in the lines below the master cylinder this way, so there's no need to bleed at the wheels.
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Wednesday, August 19th, 2015 AT 4:13 PM

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