# jeep unlimited rear end question



## daddyhoney (Dec 4, 2006)

We are close to purchasing a Jeep Unlimited Sport for use in our happy retirement. We hope to use it a lot on the Tx beaches and occasionally in Colorado where we will travel some high mining roads. Not rock crawling or really technical stuff, just fun in the out back.
My question is this...most models come with the 3.21 gear especially with the five speed automatic which I intend to get. The 3.73 can be had in the same vehicle also. Would it be a plus for these uses or would the 3.21 and associated fuel economy be acceptable? thanks for your input, GG


----------



## Fishtexx (Jun 29, 2004)

I would go with 3.73. Deep sand and steep inclines really work an auto trans. The lower gear ratio will help in that area. Most driving at the beach and wheeling on trails is at low speeds, the low gear ratio will give you better throttle response (power). Jeep should be able to give you fuel milage differences between gear ratios. I guess it really depends on how much off raod driving you intend to do. JMO


----------



## RB II (Feb 26, 2009)

Fairly obvious trade offs, power for fuel economy. But how much power is needed. For what you describe, I think that a V6 jeep with 3.2 rear end ratio would have ENOUGH power to make it up the mining roads and through the sand you describe. For me, that is why they make multi gear transmissions, to downshift when more power is needed. You can't upshift for more fuel economy when you run out of gear. I think the 3.2 would work for a lightly loaded stock jeep used as you describe.


----------



## Lancer00 (Feb 23, 2010)

I just bought a wrangler unlimited and went with the 3.73 for the increased towing capacity.

by the way...very fun vehicles.


----------



## Jolly Roger (May 21, 2004)

I had a 2007 Unlimted sport auto trans, at the time there was a choice of 4.10 gearing. This is what I had and if I would have kept the jeep any longer was going to go with 4.88 gearing. 


Get as low gearing as you can.


----------



## YamahaFan (Nov 21, 2010)

I have a new 2012 Unlimited. I purchased it with the max tow package and that includes the 3.73 rear end. I also have the automatic transmission. Fuel mileage average for me is just about 20 mpg. It is my work commuter so it probably averages 70% highway mileage.

Another thing to consider is that the 3.21 ratio is on the base models with the little 28" diameter tires. If you step up to the 3.73 you will also get the 32" diameter tires. They will give you a little more ground clearance and offset some of the gearing. 

I am totally happy with my Jeep. The fuel mileage is much better than the 1/2 ton Chevy 4wd it replaced yet it still has the ability to tow my 20" bay boat with ease. The new 3.6 litre engine is a world apart from the old 3.8 minivan engine used thru 2011 and the addition of the 5 speed auto only makes it better.


----------



## daddyhoney (Dec 4, 2006)

Thanks guys for all the in put. I think I will order the max tow package for all the benefits you stated. GG


----------



## Pocketfisherman (May 30, 2005)

Depends on how big of wheels/tires you want to run. If you're going to stay stock, the 3.23 will be fine. If you're any bigger in the future, go for the 3.73's now. The fuel economy difference will probably be about 1mpg. When you're crawling in 4 lo, the transfer case ratio makes a much bigger difference than the axle ratio.


----------



## robdog (May 10, 2006)

I just bought a 2012. It has a different motor vs. 2011 and prior. The 2012's have 285 HP vs. 202 before. It's a big difference, especially towing a boat. Just in case your considering a used one.


----------



## Flat Trout (Aug 2, 2011)

Traded my '08 with 6 speed manual and 3:21 gears two days ago. Now have a '12 with 5 speed auto, max tow pkg and 3:73 gears. Night and day difference and I don't have to shift gears anymore. We live in the nasty hills of The Ozarks in north Arkansas and my computer showed 26.3 avg MPG on the 70 mile trip back from the dealer. I never got more than 21 with the '08 even on flat and straight down in TX.


----------



## texcajun (Feb 22, 2009)

Don't know much about the Jeep you speak of, but that new 3.6L V-6 is the real deal! Having driven mini vans for my job over the last 24 years I have seen just about every V-6 Mopar has made, and the new Pentastar V-6 is without a doubt the best of them all. The low end torque is way better than any V-6 they had in the past, while the gas milage is much better than I expected. And brother, does it have legs! All I can say is I hope my company never checks the nav computer because I decided to check it's top end and let's just say, I'd never seen a mini van go that fast.


----------

