I have a Manual 07 Jeep Unlimited X (4 door) with a 4'' teraflex long arm lift. I plan on adding a 1 inch bl soon. I have 37'' tires that fit perfectly and do GREAT offroad.

I noticed a difference in driving and power after the lift install and want to upgrade a few things to increase gas mileage and power.

EVERYTHING else is stock on this jeep(besides cutting my pinch seam)... My question is: What gear ratio would be best(5.18?), and would it be wise to upgrade my clutch/tranny along with the gearing?

Also: If I don't upgrade the gears, can it damage the engine/clutch/tranny?

I have another $2k I have available to add to this jeep for the time being.

Any suggestions would help.

 

with 37's i would go with 5:13's that seems to be what everyone with 37's are running and they seem happy about it. as far as the tranz and everything goes with upgrading im not sure there is much you can do in that area. but i may be mistaken. im sure some others will tune in. but the gear thing has been beaten to death on here.

hope that helps some.

 

You can not go any higher with the X model, Dana30 front axle.


5.13's is it.


It should perform like stock with 5.13's and 37's.

 

I will be buying that gear ratio when the time comes. In the mean time - Can any damage be done to the engine/tranny/clutch while driving in the lower gear?

I am worried it could be putting stress on the engine and lowering the life expectancy... as silly as that wording sounds.

 

I'm sure its not easy on it, but I dont know of anyone having any issues running it like this. Theres plenty of people that would have spoke up by now.

 

5.38 gears. Dana 30. Summit Racing.

http://store.summitracing.com/partdetail.asp?autofilter=1&part=MGR%2D70289%2D5X& N=700+4294918962+4294776336+115&autoview=sku

 

its not for the JK.

 

I'm not sure these will work...the description provided says standard rotation, our JK front's are reverse rotation cut...

 

Really? Are you sure? I wasn't aware of that. I get confused when I'm on a creeper after six or eight beers.

 

Other than the rotation, what's the difference? I was under the impression that the front was pretty much a standard D30. Did I shortbus it?

Here are some that are reverse cut:

h ttps://www.4wdfactory.com/store/products/Dana-30-USA-Standard-Gear,-Reverse-Rotation-Ring-&-Pinions.html