nthinuf

You have an auto. The extra 10 hp from the tuner doesn't even come close to making up for the extra 2" in tire height. But it's your money, if you want to talk yourself into undergearing, go for it...

Personally, I think an auto with 5.13's/35's/flashpaq is undergeared. You could also touch base with Ripp to see which gears they run. I believe they use 5.13's even with the superchargers. And avenger suggested 5.13's when I was in talking to them about gearing...

Just found a post by Ripp:

DesignMonkey

ok, i am about to order gears and want to play on the cautious side. I run my factory 32's for my long distance trips over the mountains (between Calgary and Vancouver) which will happen regularly and some towing. I run the 35" tires when sticking near home and wheeling. I have 3.73 now behind the 6 speed and am running real heavy with bolt ons.

By the chart, i will be at 3000rpm with the 32's on the highway with 4.88 gears. Does than not seem a little high running for a 11hr trip? My thoughts is that 4.56 would be a better happy medium, but am just not sure

opinions please!!??

DesignMonkey

any one with first hand experience with the 4.56 gears?

Pluke the 2

good thread

davyjones616

I have a 2010 2 door sport with stock 3.21 gears. I currently run 265/75/16 bighorn maxxis tires and in july i want up grade to 305/7016s. I know i am under geared and i would like input on whay gearing would be best for me with that tire size and how much it would cost. It is my daily driver with moderate offroad use on the weekends.

Also.. How hard is it to change the gears out myself?

Thanks

Don1

very interesting thread. I too have been reluctant to regear as I really dont want to make a mistake in gearing. I've been going back and forth between 5.13s and 5.38s. right now with the 37s (really, 36s) auto, and 4.10s i've been averaging about 16 mpg with the hypertech programmer on the hwy, drops to 14.5 in the city. i would HATE if i ran 5.38s and then dropped down to something ridiculous like 12 mpg on the hwy with the 37s. However, the conundrum is that i'm going to be going even bigger to either 38s or 40s, so i really just dont know. according to the chart with 40s and 5.13s i'd be at around 2k rpms at 70 mph. I live on relatively flat ground at around 400-500 feet.

Culprit

Would it hurt anything if i ran my stock gears which im asuming that they 3.73 becuase i have a 6speed and the tow package and ran 35's. Also my jeep is a 2 door x.

jhol111964

It seems that most gearing threads assume "crawling" is a major activity, and many assume you have an automatic ( final gear drive ratio = .69:1). This has been a favorite thread for me, with lots of facts and data. Its probably worth pointing out to those who don't rock crawl, you can achieve a significant effective gearing improvement, by simply cruising or towing in 5th, and avoiding 6th. In my case, my 3.21 becomes a 3.84. Instant, free, "tow" package!

With the charts calc'd for 70 mph, I wonder if some folks might be fretting over something that's not an issue for them, if they just like taller tires as decor, or they are towing?

chknkatsu

look in the FAQ section.

SilverJK12

So when you look at the gear chart. Go by actual height of tire 37 tire so look at 36 on chart or look at the 37 on chart.

Another example. 35 inch tire but actually 34 so 35 or 34 on the gear ratio chart?