Hey all, I am new to this site and have a few questions concerning my 02 F250 longbed crew.

I have just installed a 4" lift with 315/75/r16 Mickey Thompsons.

I have noticed a significant decrease in mileage, shifting, and over all performance.

The ride is great compared to the steeltex tire.


Should I get a programmer or chip to correct my other problems?

Any suggestions would be greatly appreciated.

 

the proper way to correct it would be to re gear it. a little more info on your truck would be help full...year, engine, current gears, mods if any, ect?

 

yeah probably the gears, here is a conversion chart site that would tell you the right gears to have. Unfortunately they are not cheap. I have been considering lifting mine, but don't think I can handle all the expense.

http://www.4lo.com/

It says for close to factory on 35" tires you need 4.56's

 

Gearing is what's causing your loss of performance. Basically with much bigger tires, it's going to feel a little sluggish off the line.

You'll have a decrease in milage, but significant depends on your right foot. My truck gets just under 18 mpg on the highway, my parent's stocker gets 18.5 on the highway, not much of a change. If you are looking at the milage counter in your overhead console, it's no longer accurate because of your bigger tires.

Your speedo is now off as well, which means your truck "thinks" it's going slower than it really is, so now your shift points will be off. That's why your shifting feels different as well. You can correct this with a Truspeed, search google, Superlift makes it.

 

Thanks for all the replies:

Here is some addition info on the truck:

02 F250 7.3L crew/longbed I think I have 3.73 gears (No other mods yet)

I have been looking into: (What order would be best)
Air raid system (K&N)
Bigger exhaust (banks or flowmaster)
Hypertech tuner or possible a superchip.
Possible to change my gears (Anyone know what kind if costs this might be?)


Is using the truespeed better than using the Hypertech to correct the proble.

 

Welcome to the site. I have the same exact truck you have with the 315 Mickeys. I choose to mod the engine rather than re-gear the truck. First off re-gearing the truck, if you pay someone, will cost at least $800. And if you decide to go back to stock tires, your stuck with the lower gears. From my experience I don’t think re-gearing the truck will help with mileage, in fact it might hurt it. That’s what I found when I re-geared my old F150.

With the Superchip Tuner, SP Diesel Air Intake, and straight pipe exhaust, my truck runs just as good if not better than it did stock. I did these mods over a couple years and it wasn’t as hard on my wallet. I would try the tuner first to see if you like the power, I think you will. I think the Superchip tuner is more popular than the Hypertech, but you can research that on the forum. Most people prefer the Tymar intake or Ford’s AIS. Banks exhaust is a more expense system, but very good quality. I haven’t really heard about anyone using a flowmaster exhaust on a diesel. The correct order of mods is usually exhaust, intake, gauges, tuner/chip. However my truck ran really good with just the tuner.

As for the speedo being off, I went to the dealership and had them re-program the PCM for the larger tires. This will help with the speedo, shift points, and ABS. I think the Truspeed only changes the speedo.

Good luck on whatever you decide, feel free to email me if you have any questions. Got any pics of the new lift and tires?