Mechanics

BRAKING VIBRATION

Dodge Ram

2004 Ram 1500 quad, 4x4, 5.7, 38,000mi.

Hello All, One time I pulled my boat, when to my surprise, it was filled with about 600 gallons of water. Totaled around 7000-8000 lbs.
Shortly thereafter I started to experience a vibration when braking, more so at higher speeds (40+), and a loss of fuel mileage of about 2mpg.

Replaced all 4 rotors ($36 a piece, cheap enough), but not the pads (Don't ask why, but my wife and the fact that she controls the $$ had something to do with it). Still have the vibration, although not as bad. Mileage still down. There is very little pulsation in the brake pedal.

Is it possible that I damaged the shocks when I hooked up the overly-heavy boat (truck was on the stops). No fluid leaking from them. Could they be bouncing when I brake, making it feel like a warped rotor?

Is it possible that the pads are feathered? It didn't look like it when I had them off.

Thanks for any help. I'm at my wits end and my kidneys aren't taking the beating very well either!

Jim.
Avatar
MGrillSgt
October 1, 2007.



Take it around the block, get out and feel each wheel for overheating. There may be caliper hanging up. Did you clean and lube everything with the brakes? Really should have done the pads. Did you clean the hub surface completely so the rotor mounted flat?

May have a defective rotor as well.

Well, no, I didn't clean or lube anything when I did the job. There was nothing in the Hanes manual about lubing anything when changing the rotor. What needs to be lubed?

Sounds like a good idea to clean the hub before installing the new rotor. There wasn't much more than surface corrosion on it though, nothing accumulated.

So I'll try the hung caliper thing.

You didn't mention the shocks idea. Does that not seem like a possible culprit?

Thanks, Jim.

Tiny
MGrillSgt
Oct 1, 2007.
Hey Jim.
IF I am going to the point of pulling the rotors, I would do the pads. If I did not replace them then at the very least meticulously clean the points that the pads make contact with the bracket and caliper. The slide pins should be cleaned and lubed as well. Any tin clips should be wire wheeled on both sides and also lubricatd with high temp caliper grease.
Make sure the brake hose is not twisted when re-installing the caliper.
The problem with not servicing the caliper and hardware is that the pads will not move properly and will wear irregularly or create overheating of the rotor in some cases.
I believe this is still a rotor symptom, possibly a problem that has caused the situation. I don't see any relevance to the shocks. Bad shocks would be bouncy and cause cupping of the tires, but not a pulsation.

Wow! I never would have thought to do all of that, but what you describe surely makes sense.

Looks like I'll be pulling the wheels again this week. I'll do new pads and work on all of the items you mentioned.

Thanks so much for taking the time to detail all of this. I'm just amazed that I've been doing a real half-arsed job all these years!

Thanks again, Jim.

Tiny
MGrillSgt
Oct 1, 2007.
It's scary how many "professionals" don't do a proper brake job. In your case, the rotor problem is still going to be there. You need to narrow down which is the offending rotor...or rotors.


http://www.2carpros.com/forum/automotive_pictures/30961_caliper_lube_5.jpg



http://www.2carpros.com/forum/automotive_pictures/30961_caliper_lubeareas_5.jpg



http://www.2carpros.com/forum/automotive_pictures/30961_caliper_lubeareasbrack_5.jpg



This isn't the same as yours, but you get the idea.