i got a 2001 f350 4x4 at 373 gears 285-70-16 tires anyways i dont pull much
if i did it would be about 3000 max could i go with the 331 gears ive seen
only thing is i cant seem to find out witch rear end it is
i noticed after i got my stage 1 injectors installed and custom tunes i was getting mid 20s on highway. im interested to see what my 238cc injectors will do
I know that my truck tows fine with 3.55's, and I've towed ~8K. a little sluggish like that, but still perfectly manageable. 3.31's should tow up to 5k without issue, and a little heavier with a good, gentle driver LOL
is your speedo recalibrated?
the larger wheels and tires will hurt you, and I'll take back what I said about towing heavy. 3.31's would be real hard on an automatic with bigger tires and towing...
If all you do is 60 mph you are going to be running too low of a rpm with a 3.31 gear, esp with a 33" tire. The slightest hill will make it want to lug & down shift all the time. I had 4.10s, went to 3.55s but found that I had to drive 60-65mph to keep it in it's power band.They rocked on the highway doing 65-70mph+ but in the 55mph zones it was little under geared. Most of my driving is city, country roads (55mph) & I cruise 65mph on the highway so I went back to 4.10s.
If all your driveing is 60mph I wouldn't waste money re gearing. I know people with 4.10s that can get over 20mpg if they go 60-65mph. Gotta remember these trucks don't have the low end of a Cummins. Keep em in the power band & they are happier.
I found that with a chip and a valvebody I gained like 1.5-2 mpg after the break in period from the truck running better.
Mind, we don't have roads that you can go much faster then 45-55 ish on with these kind of trucks, with all the potholes and sharp corners you're likely to bounce right into the ditch if you try going much faster LOL
Anyway, I have a fairly consistent 15 mpg going 10-20 miles in town, and a 19-23ish long distance, depending on where in the country I'm at, and if I'm driving daytime or night time.
:doh:
I mixed up who I was talking to...
with stock-ish sized wheels and tires, I'd try 3.31's or 3.55's.
with 35's, I'd go with 3.73's or it's going to be a total dog.
I think the airflow mods only help those of us with imperfect driving LOL
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