So I know there is a million posts about tire sizes and gears but I did not find the answers to these questions in the threads that I read through:

1. How do I know what gearing I currently have? I have a 2010 JK Unlimited Sahara that came from the factory with 32.5 inch wheels

2. How do I know what affect different wheels is going to have on the auto tranny and power before buying/trying?

Basically everything I read said that 35's plus auto tranny = re-gear. Then I started seeing info that said it depends on the weight on the 35's (Which would also depend on the width of them i'm assuming right?) so this quickly becomes a question of, if I run large 33's, that actually measure something like 33.78 x 11.5 would I need to re-gear or not.

Since it's relevant to the conversation i'm in South Carolina, and 85% of the driving is on flat roads below 55, 10% on Highway's, and the remaining 5% off-road, mostly in woods and mud although if I could find some cooler places to wheel that ratio of 5% may change.

 

The easiest way to find this out is to call the dealer with your vin #. I can tell you that with an automatic, anything less than 4.10.s is going to be a dog trying to turn 35's. As far as tires, load range c will be lighter than d or e, but also less durable. Also I would pick up a tuner to help with the power, and also to calibrate the transmission for different tire sizes, which will affect how it performs

 

Thanks - I called the service folks and they said I have 4.10's. I have a Superchips tuner already. I'm thinking about picking up 33's or 35's, probably the 33's since I do more significantly more on-road driving than off-road. Besides years ago I went off-roading with jeeps where 33's would have been the dream to have and never had a problem.

 

You will be fine with the 4.10 and 33 set up.

I ran this on my first 2 JK's no problem and regeared for the 35's and 3.70's on this new one, dog.....