Hilldweller
SE Expedition Society
You're going to have a great time; that trailer has good karma all over it.
Think about a Superchips tune also; made my Jeep much easier to live with.
Time to regear the JK 4.56 vs 4.88
- Thread starter MuleShoer
- Start date
Think about a Superchips tune also; made my Jeep much easier to live with.
The 3.8L V6 really is happier with lower gears. Completely different powerband than the old inline 4.0L. And the 3.8L is much smoother and still relatively quiet at 3000 RPM+. I strongly recommend the 4.88's. I have driven auomatic JKs with 35's and 3.73's, 4.11's, and 5.13's. 5.13's were great all around, and for comparison, I have driven one on 37's with 5.13s. Also drove a 6-speed where we installed 35's and 5.88's. Your setup would benefit most from the 4.88's. With the auto, you are impacting your acceleration and performance throughout the engine's powerband, not just the final drive. Were in a manual you can have an impact buy changing your shifting pattern.
Chris
Chris
To me your gearing really depends on the TRUE measurements of your tires. wait until you have them on your jeep and see what they are. I have 35's but after about 40,000 kilometers they are measuring out at 32.75"
with 5.13s and barely 33" tires your gas mileage is really gunna suffer. 1st gear is pretty much useless, i barely use it unless starting on a hill.
I have a 2dr so i have a 60 litre tank and around town 0 highway im lucky to get 300kms to the tank.
on the highway closer to 450 or 500 depending on if im driving into a lot of wind or not.
if you are going to get 5.13s make sure the true measurements of your tires are as close to 35 as possible.
Mickey Thompsons are notriously bad for saying 35 but barely being 34
some good tires for acurate tire measurements are toyo open country mts as well as the goodyear mtrs with kevlar.
but then again its your jeep do what you want!:smiley_drive:
with 5.13s and barely 33" tires your gas mileage is really gunna suffer. 1st gear is pretty much useless, i barely use it unless starting on a hill.
I have a 2dr so i have a 60 litre tank and around town 0 highway im lucky to get 300kms to the tank.
on the highway closer to 450 or 500 depending on if im driving into a lot of wind or not.
if you are going to get 5.13s make sure the true measurements of your tires are as close to 35 as possible.
Mickey Thompsons are notriously bad for saying 35 but barely being 34
some good tires for acurate tire measurements are toyo open country mts as well as the goodyear mtrs with kevlar.
but then again its your jeep do what you want!:smiley_drive:
Stumpalump
Expedition Leader
I never hear I wish I gone with a higer gear set but often hear I should have gone lower. With that said 4:88's are as low as you can go on a Dana 44 befor you comprimise strength of the ring and pinion. After 4:88 the pinion gets tiny. 4:56 gears would be as low as you should go if you had a Dana 30 up front FWIW. An easy way to remember is to look and see the lowest gear set Dana Spicer makes. They won't make anything lower than a 4:88 for a Dana 44 or a 4:56 for a Dana 30 because they are weak. I know you have 44's but I'm just saying. Another thing that you rarly hear and most don't know is who makes the best, stongest, longest lasting and easiest to set up ring and pinion gears. That would be Dana Spicer on Dana axles. They are hands down the best. On the popular to swap Ford 8.8 rear it would be Ford motorsports gears. In a lot of cases you can just bolt them in and go without changing shims. The setup will be that close. Good luck on your choice. You have to decide do I want best power and performance (4:88) or do you want to squeeze that last MPG out with the 4:56 on your freeway drive. You live in mountains. Thinner air make s less HP and the hills bog it down . Go 4:88's.
MuleShoer
Adventurer
Stump
Maybe thats my problem the thinner air:sombrero:
Here in SW virginia we are at the 2500-3500 foot level whic is nothing compared to out west.
Becausing of the need to tow our trailer I think I am going with 4.88's, I hear the Yukon Gears are pretty decent
Thanks
I recommend the 4.88 for the manual, and 5.13 for an auto. I have the 4.88's @ 6-speed w/ 33's, and couldn't be happier. Note, that 4.56 are really hard to find, even if your favorite catalogs show them, nevertheless, i wouldn't go 4.56, especially w/ an auto and tons of hardware leeching on you for wind drag. Good luck!
CGwelder
New member
Look at it this way, there is very little change from 4.10 to 4.56, period. My Rubicon is a dog with 4.10 gears and stock tires, the thing that helps the most is that it's a manual. If I were you I would be thinking 4.88 or 5.13, and a heavy duty trans cooler with it's own electric fan. Nothing ruins your day like a fried transmission. I had 4.88's in my CJ on 35's and it ran great but I could not imagine towing with it.