I can share some observations but I've never used them myself. The friend I spoke of has a body / repair shop and he specializes in rebuilding smashed one and two-year-old Dodge trucks. He had one of these boxes on a '99 dually diesel that he rebuilt. He was already using it to pull a three-car hauler to transport cars he was rebuilding for another business about 250 miles away. He also used it for plowing snow in the winter for local businesses. As it was, he left it in two-wheel-drive and just idled across the parking lots to push the snow. No real need to get a running start or use 4wd. The power was amazing but he had a bug that told him he needed more. After installing the chip, with more power, of course he "needed" to use it, and he promptly tore up the transmission. He bought a professionally rebuilt and beefed-up transmission and a special torque converter to handle the horsepower, but now the truck just sits because he has two newer ones that he rebuilt.
The next one was a '96 that came out of Salt Lake City. It was hit so hard in the front end, it pushed the engine back over a foot into the firewall. My job was to rebuild the crushed heater box, and I helped him, (learned how to), weld in a new firewall and straighten the frame. This is another dually diesel, and he wanted me to install a chip in this one too. My strong suggestion was to let me fix the smashed plugs for the under-hood computer and get the engine running first, THEN put the chip in so there's not so many variables if it didn't run. Nope; had to do it right away to make him happy. The first night he took it out for 20-minute test drive he came back with this stupid grin on his face, then he took us out to eat. (That's my pay for the hours of hard work). I've driven a Viper a few times after changing the oil, and I got a ride in one once. That was nuts, but this truck will almost keep up to that. Later he took it to a local fuel injection shop and they determined the truck already had an over-size turbocharger and over-size injectors, and now it has that chip. They estimated it is pushing around 700 horsepower and 700 foot-pounds of torque. This truck has a six-speed manual transmission, and the clutch is the weak link in the chain. Dual rear wheels are hard to break loose, so it's the clutch that slips if he really gets on it. The truck can easily get 23 miles per gallon, but adding speed or load cuts that by quite a bit. He recently moved his sister from Texas back here to Wisconsin, and he built a huge box onto his 32 foot goose neck trailer, then severely overloaded it with all her personal stuff and three horses. That trailer was bottomed out on the axles, one wheel separated, and he broke all the lug nut studs on two pairs of wheels. Took him a day to drive down there but three days to get home with all the expensive repairs on the side of the road. We've estimated he was pulling 38,000 pounds of trailer. For the first time he was limited to 55 miles per hour, and he was down to 9 miles per gallon, but he made it home.
His latest project is a 2011 Dodge Mega Cab that he is extending. Those only came with a six-foot box. He bought a frame that came from an experimental truck right from Chrysler and used the rear half of it to extend the truck 20" so he could put an eight foot box on it. My job so far was to repair the crushed wiring and extend it to the rear, and modify the brake line, fuel lines, and fuel filler pipe. He's painting the front of the truck today and I'm headed there shortly to help him hang panels on it. He wants a chip put on it too. Most importantly, he removed the ridiculous exhaust system our stupid politicians demanded it come with. That should increase his fuel mileage by five miles per gallon.
One thing I've heard from a number of people is if you have a Traveler Computer that shows your average and instantaneous fuel mileage, that reading will be wrong. Most people say your mileage WILL increase, but not to what is displayed. These chips alter some of the sensor readings the Engine Computer uses to calculate fuel metering and it's those calculations that it uses to determine the miles per gallon to display. One fellow with a gas engine in a Dodge said he was getting 19 miles per gallon but the display showed 28 mpg. I don't know what is original fuel mileage was but from what I've heard, 15 to 17 was typical.
Also be aware all of my buddy's trucks are diesels which respond to fuel quality more than gas engines do, and he does other modifications like installing 5" diameter exhaust systems to help them breathe. One other thing he is a stickler for, and not to rehash my previous reply, but makes sure they're exactly at the proper ride height, then takes them to his favorite alignment shop. Being a suspension and alignment specialist, I can't help but look at the tire wear patterns on his stuff every time I go out there, and the wear is always perfect. Proper alignment when the truck is in motion is a big contributor to good fuel mileage. The very poor suspension designs on Ford products, especially the miserable twin I-beam suspension, are a big reason Fords can't compete when it comes to fuel mileage, and they will never get decent tire wear. Your truck will have the upper and lower control arms which keeps the tires in proper alignment as you bounce down the road. That, and drive shaft angle are two of the biggest contributors to good fuel mileage, more power transferred to the road, and minimum drive line vibration.
One last comment has to do with warranties. All manufacturers will not honor engine or drive train warranties if a mechanic at the dealership finds a chip on the truck. Some owners remove them before taking the truck in for repairs, but we have one well-known chain tire shop in town that does a lot of work on heavy trucks and farm machinery. If a newer truck comes in there with a chip, they will call the dealer and inform them. Apparently they are getting some type of financial incentive or reward for this, then some dealers use that information to deny warranty service. I don't know if this takes place anywhere else but it is something to consider if your drive train is still under warranty.
Tuesday, September 24th, 2013 AT 1:27 PM