BF Goodrich Rugged Terrain T/A 235/75-16, new to market

[LaGrasta]

I had America's Tire order these for me and they are pretty cool, ride nice and have the aggressive look I wanted. Plus, I couldn't afford to replace my BFG KOs, the prices have gone up. These were $121 each.

http://www.americastire.com/dtcs/tires/ ... &pc=38616
With my new aftermarket 16" rims, I had to trim some more wheel well due to slight variant in offset, but the trimming is hardly noticeable even to me. The wife hasn't said anything; good sign.

The taller wheel is putting too much drag on my tranny; temps are up, jack rabbit starts are slow. I had swapped my rear end years ago in the wrong direction in my pursuit for better MPG. I'm running 3.23. I'm going to swap again, thinking about 3.73. Advice?

[MountainManJoe]

try to get a whole axle so you don't have to do the gear setup.

[LaGrasta]

I hadn't considered that. I actually have a very good friend that is a professional mechanic, although I haven't asked him yet, I expect he'll come to lend a hand. Hopefully, he knows how to set them correctly.

[LiftedAWDAstro]

The taller wheel is putting too much drag on my tranny; temps are up, jack rabbit starts are slow. I had swapped my rear end years ago in the wrong direction in my pursuit for better MPG. I'm running 3.23. I'm going to swap again, thinking about 3.73. Advice?

Where you drive, is it relatively flat? Do you do any towing? Do you run loaded (the van that is! ) a lot? Are there ANY plans to go to a 4" lift and taller tires? If it's hilly or a lot of city driving, you tow loads or run with the van full of people or stuff a lot, I would go right to 4.10's.

[LaGrasta]

No plans for a higher lift, but I do drive loaded ( ) about 15% of the year (camping, traveling, people hauling, etc.) Most driving is freeway 25 mile trips. For MPG, what do you recomend, still the 4.11?

[LiftedAWDAstro]

I highly recommend going right to the 4.10's. What do you get for mileage now with the taller tires?

[LaGrasta]

on average, I'd say about 15mpg

[arlon]

I'd second the "go to 4.10/11" idea. I have 3.73 with 225/75/16 Es and it is a noticeable drag (tires are heavy too). I'm not even sure if I'll be able to comfortably tow my new little camp trailer with it. A set of 4.10's I think would do wonders for it, maybe even improve mileage as I could run closer to the power band of the engine. Either 4.10 gears or swap in a V8 or 4BT cummins... Gears are probably cheaper.

[LaGrasta]

Thanks for the input, that is a real live example for me to measure what to do. 4.10s it is…
I have a good friend that has a set of 4:10s from his Jeep, Dana 40. Will those fit our 10 bolt 7.5 differentials?

[LiftedAWDAstro]

Dana gears will not fit. No luck there. Gotta get either gears from a GM 7.5" or 7.625" rear. If you get used gears from say an 80's S-10 or Astro, those work perfectly as they interchange.

[LaGrasta]

thanks for the info.

On the search for affordable 4.10s…

[LaGrasta]

I went here to do the calculation and now I'm confused,
http://www.gounitrax.com/afterratio.htm

stock height is 29" and now I'm at 30", is this correct?

[LiftedAWDAstro]

Stock diameter is 27.7" not 29".

[LaGrasta]

Thanks.
Using their formula, it puts me at a desired 3.73 gear.

To swap these out, does the axle have to come out of the van?

[LiftedAWDAstro]

No the axle doesn't have to come out. If you have access to a lift then it makes life easier to leave it in. If you are doing it in the driveway like I am, it is easier to pull the axle out.