Biggest tires without regearing

Here's some simple math to determine wheel size/gear ratio final rpm & crawl ratios:

•Crawl Ratio = Transmission Low Gear x Transfer Case Low x Differential Ratio i.e., 6.68 x 2.46 x 4.88 = 80.2
•RPM = (mph x transmission gear ratio x axle gear ratio x 336) / tire diameter i.e., (65 x 1 x 4.11 x 336) / 33 = 2720 rpm
•MPH = (RPM x Tire Diameter) / (Gear Ratio x 336) i.e., (2500 x 31) / (3.73 x 336) = 61.8 mph
 
After getting input from quadratec and my local shop manager who specializes in jeep mods, I decided to go ahead and put 35"s on my 2009 JKU with the 3.8 engine and 3.73 gears. I live in East Tennessee close to the Smoky Mtns. I travel up hills and mountains frequently. Is there a difference between the 35s and 32s I ran before? Yes, but it's minor. Took it on a few trails in the mountains and didn't have any complaints. In Everyday driving, it is barely noticeable. Now, regearing is probably at the bottom of the mod list for me. I suppose you can always regear if you really hate the performance after adding the tires.
 
Brute said:
Here's some simple math to determine wheel size/gear ratio final rpm & crawl ratios:

•Crawl Ratio = Transmission Low Gear x Transfer Case Low x Differential Ratio i.e., 6.68 x 2.46 x 4.88 = 80.2
•RPM = (mph x transmission gear ratio x axle gear ratio x 336) / tire diameter i.e., (65 x 1 x 4.11 x 336) / 33 = 2720 rpm
•MPH = (RPM x Tire Diameter) / (Gear Ratio x 336) i.e., (2500 x 31) / (3.73 x 336) = 61.8 mph
Click to expand...

Good info, and nice Brute!
 
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