Hi all, usually I am lurking in the OBS powerstroke section.

But just picked up a 94 F150 4x4 with the great 300 6 cyl engine and the 5 speed manual. It has 3:08 gears according to the tag. It also has a limited slip, but I imagine the clutches are bad.

My question is, with the 3:08 gears will going to the 265/75/15 tire from the 235/75/15 kill the performance?

I live in a hilly area.(14747 zip) The truck will be used for light loads and light towing and daily transportation.
I have the HD powerstroke 2wd for heavier work.

The difference in size is listed as 1.75 inches.

I would appreciate feed back. I couldn't drive the truck with the 235's to see how the performance is. Now that I have it fixed will be the first time driving it.

Thanks, Joe

 

Performance. From a 300 powered truck.

Ok... in all seriousness here's my 2 cents. For actual use as a truck the thing should have come from the factory with 3.55 gears, 3.08s are good for gas milage but they are murder on clutches pulling loads from a dead stop, and in hilly terrain the gearbox is essentially reduced to a 3 speed because even with the I6's 0-3500rpm powerband the truck can still do 60mph in 3rd gear.
Yeah the truck will manage as is but it's far from ideal and larger tires are gonna make the situation even worse, so mabe consider swapping in a rear axle and front pumpkin from a junkyard truck.. 3.55s were very common in 5.0 and 5.8 trucks.

 

That's the first I've heard of 3.08s in a 4x4 truck. I'd be looking for more.

 

My buddy in high school had a 1993 f150 with a 5.0 5 speed and it had 3.08s. He had true dual straight pipe exhaust and when he would run 55 in third gear that ol rip would SCREAM!!

 

sadly,my 5.0 4wd has them

 

I hear you loud and clear. I have had 4x4s steady since 1983. They never had less than 4.10s. So this is new area to me. And I didn't get to drive the truck before hand due to brake problems.
This is more for my daughter who has horses, we live on a farm.
So it will haul small loads. For pulling the animals we will use the diesel.

My main winter transportation is a 94 80 series LandCruiser that has 4.10s and front and rear lockers. It it also underpowered with a 6 very similar to the power of the Ford 300.
But with the 410s it will pull strong but at low speeds.

I can get a great deal on the 265s from my cousin who ran them for about 1000 miles.
I will probably be better of staying with a 235/75 since a gear change is not in the cards right now. To many projects, to little cash.

Thanks for all the opinions guys.

Joe W.

 

I was very surprised also.
It will be nice for mileage on flat land.
To bad I don't have much of that around here.

 

You guy will probably be surprised to learn that 2.73 gears were also a common option in 1/2 ton I6 trucks.

 

Going from 235/75-15 tires (28.9" OD) to 265/75-15 (30.6" OD) would be the equivalent of keeping the same tire size but changing your 3.08 gears to 2.9 gear.

Would it kill performance? I wouldn't think it would be that significant. But it will be going the wrong way on a truck that is already pretty low performance.

 

I don't remember what gear ratio my '91 had, but considering that it had absolutely no passing power in fifth, it wouldn't surprise me at all if they were 2.73s.

My '93 does all right with the 3.55s, though I have yet to tow anything with it (and it would be nice if I could turn a little less than 2,500 RPM at 50 MPH in fourth). Joe would really benefit from a gear swap, especially if he does a lot of freeway driving. Were it my choice to make, I'd go with 3.55s or 3.73s.

 

I agree the change isn't big enough to be a major difference.
But, like you said it's the wrong way. I haven't decided yet,
But am going to price new 235's this week. I am leaning on going that way.

A gear change isn't going to happen anytime soon.


Thanks, Joe