Changing rear ends

[robs72]

Any advice on a little better freeway gear ratio on my 72 f250 360 2bl, 2wd... Looking for a little better cruising, rather than pulling.

Thanks

[70_F100]

What's the gear ratio that's in it now???

[Caseys71]

What's the gear ratio that's in it now???

, But most guys that are just using there trucks for cruising and looking to get decent MPG's usually go with around a 3.25 ratio that's with 235/75 tires, in theory you could just run a taller rear tire than what you have to get a higher gear ratio which would be better for cruising. Then again it would depend on the ratio you have now, and the tire size you have now.

[fordman]

i have a 3.25 390 with a c6 in my truck. and it pretty much gets 10 mpg. about a 1/4 tank for 15 miles and maybe back i think it used to run.

[70_F100]

i have a 3.25 390 with a c6 in my truck. and it pretty much gets 10 mpg. about a 1/4 tank for 15 miles and maybe back i think it used to run.

I've got 3.25 in mine, and with a C6 and 360, just like Fordman said, 10 mpg. That's uphill, downhill, headwind, tailwind, empty, loaded, towing, even just sitting in my driveway...

Since I put the T19 in and swapped to 265/75-15's, I haven't driven it anywhere except around the neighborhood, so I don't know about the mileage. I'm pretty sure that going to a manual tranny and larger tires will help, but I still don't anticipate a lot of improvement.

[robs72]

Thanks for all the advise, I am currently runnning 3.73 stock gears. I will look into the 3.25, it sounds like what I am looking for.

Thanks Again to all

[ScreaminZ]

I could be mistaken, but I don't think you're going to find any gear ratios numerically lower than 3.54 if your rear axle is a Dana 60. These other guys talking about a 3.25 ratio are more than likely talking about F100's with a 9-inch rear end.

[70_F100]

I could be mistaken, but I don't think you're going to find any gear ratios numerically lower than 3.54 if your rear axle is a Dana 60. These other guys talking about a 3.25 ratio are more than likely talking about F100's with a 9-inch rear end.

Yep, that's what mine is.