2008 F150 Limited Edition AWD
I decided to go ahead and put a 6 inch suspension lift on my limited. I love the way the truck looks i got luxury and i also got that raw look of an offroad vehicle. I installed a K&N Cold Air intake system and bought a BULLYDOG Performance tunner (GT) prior to the lift.
I put in a 6 inch ProComp Lift with the MX2.75C C in the front and the MX6 in the back. Followed by 33 inch Nitto Terra Grapplers.
Now heres my problem... I lost LOTS of power, and my Miles Per Galon (MPG) has terribly gone to the floor and Gas is killing me making me want to consider getting rid of the truck, which is something i do not want to do.
Im not too familiar with the whole gears situation, if anyone could help me out with this and show me a website where i could order the parts?
Thanks in advance,

im gonna try to post up pictures soon. Hopefully mine can be in the TOTM list one of this months

 

im assuming you have 3.73s. I wouldnt bother regearing with only 33" tires. The ideal ratio for 33s wouod be 4.10 and the difference is so little you will not notice much if anything. A truck with a lift kit is like a brick going down the highway, once you lift a truck your fuel milage will suffer and no gear change will help. Ive been there. If you plan on jumping up to 35s id put in some 4.56s but again it doesnt help as much with fuel economy, mostly just gives you your power back.

 

I'm glad to see you post your true impressions. You're not the first to go after the aggressive look to find out it's not without significant consequences. Unfortunately, you'll find it's just as depressing to get rid of a truck with that sort of lift, especially in this economy. You probably should have gone with a leveling kit, because a 33" tire will easily fit with just a 2" leveling kit on a 4x4.

A few things that you may need to consider. If you have. 3.55 gears, you need to step up to 4.10s. Some lifts have more than a specific lift for a given kit. You may be able to drop to 4" with a few change in components. If you haven't recalibrated you speedometer, larger tires will distort you mph. Your odometer is off which also impacts the message center mpg, if you're gauging mph from it. Unfortunately it won't be more than 10% off. A tuner can help get things normalized, as well, because your PCM is making calculations off of erroneous inputs.

Going for an aggressive look is one thing, but lift kits and tall tires are intended for ground clearance. If you don't go offroad, you're spending money to spend more money without any benefit. Performance falls off and you begin to hate your truck. I've been in this game for many, many years and I see the same mistakes made time and time again. Hell, I've gone with more tire than I needed for what I did, but gas was relatively cheap when I made those mistakes.

Trucks are made with a sufficient tire size for more than any mild off-roading now a days. To do a lift with large tires and appropriate gears for your bigre sizes is mega-bucks to do it right, but there's no way you can expect reasonable gas mileage, much less performance.

I'm sure I'll get flamed for what I've posted, but this is honest information. Err on the side of conservatism. There's nothing wrong with an aggressive look, but know it comes with a heavy penalty. Gasoline prices can only go one way from where they are now.... UP.

 

well said

 

Windsor, I think you are absolutely right, and i was very satisfied from your response. Ive definetly realized that i made a huge mistake lifting the truck and getting the big tires,i know i should have kept it stock or like you said a leveling kit might have been enough.. But the only solutions i have now is either 1. Improve it, trying to do something to make it at least a little bit better or 2. Getting rid of it. which if your a truck owner you know how hard it would be. I mean i know i say i wanna get rid of it, but i gotta be honest im in love with that thing man... Not to mention the fact that i need the heavy duty suspension and the clearance for work. And cant live without taking it offroading.
Now back to getting the issue of getting my power back.. im planning on getting 35's on the front after my terra grapplers are worn out. Should i wait to get the gears until then? or should i get them now? Is there a specific brand that you could recommend to me? it seems like you know what you're talking about pretty well. Maybe a link where i could purchase it.

 

Oh and also, how do i fix my speedometer?

 

Most tuners provide you the opportunity to change your tire size, as well as gears, in the PCM. If you will ultimately end up with 35" tires, you want to gear for that when you do re-gear. 4.56s is probably the best set for that large a tire, but is a little steep for 33" tires. 4.10s would be the better gears for 33" tires, and would still give fairly decent performance with 35s. But if you go off-road, I'd recommend the 4.56 gears.

Swapping gears is pretty significant cost, but as far as when to do it, I don't think it matters. In my last lifted truck, I changed gears before I installed the lift and bigger rubber. Unless you've done it before and know how to do it, you will probably have to have someone install the gears. It's precision work and you need a few specialized tools to get it right.

You can find gears in most performance vendors. One of the vendors that specialize in differentials and have gears for our trucks is Randy's Ring and Pinion. Most gear sets I've seen listed on that site that fit the 9.75 and 8.8 are made by Yukon gear. Precision gear and Richmond gear also make good gear sets, but I don't know that they make sets for the larger Ford rear end. You need a reverse rotation set for the front end, so not all 8.8 gears are the same. I presume you have a 4x4, so you will have to change both front and rear gears.

If you set your truck up right, it'll make it more fun to drive, but all that weight can't be overcome. It will use more fuel and performance will still not be on par with stock. Your brakes were also designed for a 32" tire, so keep that in mind when you're out on the road. Baer makes a larger rotor that fits on our trucks that has a larger diameter. That would also help braking better. If get that stock power back, and then some, look at installing a supercharger. These things are amazing.

 

I believe he said AWD, not 4x4. I don't think it matters much.

 

Pics please.

 

yea lets see pics always curious to see a lifted limited.....damn awd though that will kill MPG like woah.