Back in 2001, I purchased a 95 F150 SC LB 4x4 with a 302 and AT and about 57,000 miles on it. It's not my daily driver, and I only put about 2,000 miles on it each year, so she has about 63,500 on her. She's in excellent shape, and I had her thoroughly gone through by a Ford dealership last year.

My problem is a major lack of power, especially when hauling or towing my small boat. When I am towing/hauling, I have a hell of a time getting up to speed and keeping up with traffic. My mechanic buddy says I should get a power chip. My uncle says my problem is the tires are too big.

The truck came with new Goodyear Wrangler AT-S tires, size 32x11.50R15. I have a pet peeve about dealers putting new tires on used vehicles, I'd much rather choose them myself. Had it been my choice, I would have picked a stock size tire with a more highway-oriented tread.

The stock tires size--as indicated on the door post--is P26575R15, about 1.5 inches smaller than what I have now AFAIK. When I do a search on most tire websites, they recommend P23575R15. I wonder if a tire that small would look stupid on this truck.

My buddy says it won't make much of a difference going to smaller tires. I'm still thinking of getting new tires and selling the old ones, or finding someone who wants to swap. Should I get new tires? What should I sell the old ones for? Thanks!

 

Going to smaller tires will help you out in the power department but I don't think its going to be as noticable as you think. I went from 255/70/16 to 265/75/16 and I could tell a difference, but it wasn't TOO bad. What I would reccommend swapping the tires out for a set of 31/10.5. This will be very close to the stock size if its listed as the 265s. Currently my dads truck is running that setup and its pretty good. Then I would look at a power programmer. This will also help with the towing power. You also might want to look up the gearset you've got in your axles. Some came with 3.08 or 3.27 gears which will lead to no power.

 

Hmmm, I don't know the rear end ratio. Would I get that from the VIN number or is it on the rear end?

Radem

 

Powerstroke, you reduced your effective gearing by 5%. You may not have noticed it, but you have at least twice the torque reserve that a 302 has, especially a 10 year old one.

Radem44, Picking up some smaller tires will help your towing situation out a good bit, as would a gear swap. However, a gear swap on a 4x4 is a lot more costly than a new set of tires. If you have a GPS, I would test the speedo. If it is off by 5%, or 8%, then that would be a good amount to reduce the tire circumference by.

The axle code should also be listed on the same sticker on the driver's door or jam.

Here is what they are:
19 = 3.55 open
H9 = 3.55 LSD
26 = 3.73 open
B6 = 3.73 LSD
27 = 3.31 open
18 = 3.08 open
25 = 4.10 open
B5 = 4.10 LSD

 

My 4.6L has twice the torque reserve as an old 302? I don't think so.

 

OK, checked the axle code. I have H9, the 3.55 limited slip. Using a gear ratio converter, the 32-inch tires bring the ratio down to 3.38, about a 5% decrease. With a bigger motor this probably wouldn't be a problem, but with my 302...I'll have to seriously look at swapping tires. Thanks for the help folks!

Radem