Gear Ratio Question

[Katterinablu]

Hi,

I'm a Wrangler Virgin and I will be changing my stock tires on my 06' SE to 31x10.5

I have already done the calculations and know which gear ratio I need, but I just wanted to ask, do I have to change anything else apart from the ring and pinion?

Like I say I am completely new at this, and probably wont attemp the job myself unless its very easy.

Any help would be appreciated.

Thanks

[neon_rt]

Changing the R&P is a procedure that takes a high amount of mechanical skill and special tools and gauges to do the job. It would help to have more information such a the axle types (Dana 35c,44 or other), transmission type (auto / manual) and what your expectations are.

[Katterinablu]

Originally Posted by neon_rt

Changing the R&P is a procedure that takes a high amount of mechanical skill and special tools and gauges to do the job. It would help to have more information such a the axle types (Dana 35c,44 or other), transmission type (auto / manual) and what your expectations are.

Thanks for you reply. In answer to your questions:

I have the stock axel Dana 35 i believe

Manual Transmission

Basically I understand that having 31" tires with my 3.73, will make it feel like I'm running a 3.18 is this true? I would just like to balance everything out. This sounds like an expensive job. Could you give some advice as to what I can do? My stock tires are pathetic. Generally when people get larger tires how do they compensate?

Thanks

[DwightRGV]

You may want to live with the tires a while before going to the trouble or expense of changing gears. I drove my 98 TJ and 3.73 gears with 33" tires for 6 years. It is not the best, but you get use to down shifting. I only changed my gearing because I broke several teeth on my rear ring gear and one the pinion.

[csparks78]

Originally Posted by DwightRGV

You may want to live with the tires a while before going to the trouble or expense of changing gears. I drove my 98 TJ and 3.73 gears with 33" tires for 6 years. It is not the best, but you get use to down shifting. I only changed my gearing because I broke several teeth on my rear ring gear and one the pinion.

Hey not to get off track here but My 01 TJ SE was in the shop last week because of a stolen PCM and I was at the Jeep safari in Moab so I rented a 06 Sport and a little bit into Fins and Things a 3 1/2 out of 5 trail I tore the hell out of the ring and the pinion gears barely made it out of there. My question is how hard are they to break??? I broke them so easy im going to be scared for awhile now with mine. I heard on the trail from some guys that they are hard as hell to break... was it maybe because it was a rental???

[Katterinablu]

Originally Posted by DwightRGV

You may want to live with the tires a while before going to the trouble or expense of changing gears. I drove my 98 TJ and 3.73 gears with 33" tires for 6 years. It is not the best, but you get use to down shifting. I only changed my gearing because I broke several teeth on my rear ring gear and one the pinion.

Thanks for your reply. 6 years is a while, So you would have kept the 3.73 if you didn't bust you gears?

I'm happy to keep the gears, but I was under the impression the engine would have to work harder, and I wont even mention the ridiculous acceleration I will get... but I guess I didnt buy a Wrangler for the speed.

Incidently, how much did it cost to replace the gears?

[fredjacksonsan]

Check out these sites, they will give you an idea of how your tire size will affect the ratio:

http://www.dakota-truck.net/TIRECALC/tirecalc.html

and

http://www.1010tires.com/TireSizeCalculator.asp

Both will give you an idea of the % that your speedometer will be off, which in turn will give you the % change in your effective axle ratio.

I'd have plugged in the numbers, but don't know what your stock tire size is.

[fredjacksonsan]

Oh yeah, and also the Wranglers with the 30" tire package come with the 3.73 ratio, so 31" isn't that much more; DwightRGV has a good point - live with them for awhile, you may find they're ok.

[neon_rt]

If you have 3.73 gears, they should work OK for you.
The standard gear set for a Wrangler w/manual trans is 3.07.
The standard size tires are 28" with the 3.07s, with the 3.73s you could go up to 34" before you would reach the same RPM/MPH as the standard setup.
My Cherokee 5-speed has 3.07 gears. It seems a little high and it goes too fast in reverse, but I can live with the 22mpg I get with it, so I will leave it be.

[Katterinablu]

Thanks for all your advice. I've decided to stick with the 3.73 gear ratio as I will probably only ever run a 31" tire because I'm not a hardcore 4 wheeler anyway Plus you guys seem to think its ok, and as you know way more than me I'm sure I'll be fine.

[Ray H]

I may be wrong about this but isnt your Jeep a 4 cyl? I thought the 4 cylinder Jeeps with the 6 spd come with 3.73s.
I think that if you have the 4 banger with 3.73s and go to 31s, it will pretty much suck.

[fredjacksonsan]

Good point, Ray. SE's with the 4 cylinder come with 4.10 gears.

[Ray H]

Originally Posted by fredjacksonsan

Good point, Ray. SE's with the 4 cylinder come with 4.10 gears.

They used to prior to the 6 speed tranny. Ill have to check this out but I think if you go to Jeeps website, they show the SE with the 2.4 and 6 speed as having 3.73s.

[Katterinablu]

Originally Posted by Ray H

They used to prior to the 6 speed tranny. Ill have to check this out but I think if you go to Jeeps website, they show the SE with the 2.4 and 6 speed as having 3.73s.

Mine is the 2.4l 6-speed and it does have the 3.73 gears. So you're saying bigger tires are gonna suck with my engine? I know I'm going to be slower, but do you think its going to be ridiculous?

[fredjacksonsan]

Originally Posted by Ray H

They used to prior to the 6 speed tranny. Ill have to check this out but I think if you go to Jeeps website, they show the SE with the 2.4 and 6 speed as having 3.73s.

Oops, forgot about the 6 speed.