I have a 1999 ram 1500. It has 16" stock rims which I currently have 265/75/16's. I was going to put 285/75/16's on, but I now am going to acquire a set of the 17" Off-Road rims from a 2001 1500. So I plan to instead go with 285/70/17. Here are the specs:

265/75: diameter=31.64, radius=15.82, circumference=99.39, Revs per mile=657.3
285/75: diameter=32.83, radius=16.41, circumference=103.1, Revs per mile=633.5
285/70: diameter=32.70, radius=16.35, circumference=102.7, Revs per mile=636.0

I already confirmed with a dealership and an independent tire store that the rims will fit fine (no issues with mine being drum on rear whereas 01 was disc on rear). I also do not plan to actually put them on until I have changed my 3.55 gears to 4.11. I will also be able to adjust my speedo to compensate for the diameter (Hypertech).

My question is, will it cause any problems with my transmission shift points or anything like that given the difference in circumference/radius and revs per mile, etc...? Any other issues I should expect.

Thanks.

 

I have a 01 w/ the off road package and the 17" wheels and I have drum brakes in the rear. I wish I had disc's instead.(easier to change.) Sorry, just realized I came no where close to awnsering your question.[sm=bangbang.gif]

 

"My question is, will it cause any problems with my transmission shift points or anything like that given the difference in circumference/radius and revs per mile, etc...? Any other issues I should expect. Thanks. "

I would think the shift points are tied to RPMs and not MPH.

I have an old work truck that I had changed over to 4.10 and the only issue I really saw was the reduced top end.