My Jeep is a 1997 Wrangler with the 4.0 and a 5 speed. It has the dreaded 3.07 gearing. Dana 30 in the front and Dana 35 in the rear (I assume.) I have 265/75-15 tires on it and I doubt I'll go bigger, but may. I have a 2" lift that came with the Jeep, but is not installed. I'm going to add it on there. It also came with a brand new Smittybilt XRC9500 winch that I'm going to install too. Right now the Jeep is adequate, but I rarely use 5th gear unless I'm running over 70 on the interstate and 1st gear doesn't quite seem low enough for some of the uphill sections of the trails we were on the other day.

I know I should re-gear to at least a 4.11, but I seem to have read that I might have to change the housings. Is that right?

A shop in Fort Payne told me anywhere from $1200 to $1500, but they need to see the Jeep to give me an accurate quote.

Suggestions?

Advice?

I don't think you will have to change the housing, but likely the spool will need to be changed, jumping that far in ratio. I've had to have a rear end rebuilt, and it was about that 1000 with a new ring and pinion. Best thing is make sure someone who knows rear end set up does it. The dealership that did mine called and told me I needed a new rear end because mine had to be bent, as they couldn't get the pinion crush sleeve to collapse and set preload. They were trying to do it with a 1/2" ratchet.

I think it's the carrier you have to change if you go much bigger.....maybe beyond 3.55? (research it on JeepForum or WranglerForum, don't take my word for it). The problem with regearing the D35 is that it's already a pretty weak diff. If you regear it, you'd do well to at least consider chromoly axle shafts. I think the "Super 35" kits include the shafts and carrier.

Your other option would be to keep an eye out for a D44 out of a wrecked jeep and swap it in, then you only have to regear the D30 up front.

If my memory is right you’ll need thick cut gear set to use a 3.55 and down carrier or use 3.55 and up carriers with those ratios. If that the price for front and rear that’s not bad.

You won’t regret it. That’s all I have to add.

Those 3.07 are a dog and a slow one at that. I had 3.73 with a 5speed and 4.0. It was great for cruising at 70mph at 2600 rpm, And had plenty of power on low end. I now have a stock d44 4:11with a 6 speed and the rpms run a little higher 2800-3000 rpm @70mph, but you don’t ever have to downgear on the interstate. Both had 33x12.50 tires and lifted. If you are going to use it for trips or any interstate driving, I recommend the 3.73. You can probably just buy and axle and do a swap, especially if you are staying with the d35. They can be readily bought cheaply. If for piddling on backroads and trails go with the 4:11.

Is there not a way to just do a swap? Your rear axle should be worth quite a bit too. Though if I was using a Jeep for driving mostly rather than one for only off-road I'd stick a 3.73 diff in.

looks like you beat me to it.

Set you up a little algebraic equation and figure the ratio you need with your current tire diameter. Unless they've changed Dana diffs, over 3.73 you can use a ring gear spacer and not have to buy new carriers. If you aren't ever going with bigger rubber I bet 3.73 is gonna be just right. Should only have to buy ring and pinion sets to do 3.73. Get someone to set them up that knows how to do it correctly .

Here is my take.

I would change to a 4:11. You can get those for a 35 with no problem. You are not going to be doing anything that will break that axle. Your not going to be doing any extreme off-roading. $1,500 for both axles is a good price.

Good luck finding a TJ Dana 44. They are few and far between. Unless you find a freshly wrecked one, I promise the 44 has been removed. I talked to Palmer Brothers about one and they said they have a long list of people looking for one. An aftermarket one is going to cost you close to $5,000 to buy and have installed.

As for the 3.07. I promise it will climb what ever you need if you have it in first gear and 4 low. I know, I’ve done it.

If I was swapping gears I would go ahead and put a locker in the rear at least.

That's a fair point about the D44 being hard to find. The other option (if a swap was being considered) is a Ford 9" out of an Explorer. I think those are quite a bit cheaper and more readily available. But yeah, 33's and light off-roading, the D35 is more than likely going to be fine.

Elite off road in Chelsea. I have heard good things about them.

Lots of discussion on https://www.wranglerforum.com/. I'd look at one of the Super 35 kits if I was regearing. If you're going to have a shop do it, have them source the parts so there are no warranty issues in the event of problems.

I've had TJs with 3.07 and 3.73 gearing. My current TJ is a 3.07 and I'm running 32x11.50 BFGs. I'll likely regear to 4.56 and go to 33s when the 32s are ready for replacement.

Did a little tire research , looks like your 265/75-15s are only 30.5 to 31" tall. No way I'd go lower than 3.73 , heck 3.54 would liven your machine up. 3.73 is gonna be lower than what it was with factory rubber so you would have gearing to go up in size if you ever want to. I guess yours is a road machine . I guarantee 3.73 will have noticeable gitty up. 4.11 gonna make it turn way more RPM and burn more fuel. If it were a woods/hunting rig you rarely drove on pavement that would be different IMO.

My real world thoughts also. I drive my jeeps places, if you go over 30-50 miles at 60mph+ you won’t like running that engine rpms high, once again 2dogs is spot on.

They are great. Probably the best off road shop around Birmingham. I’ve used 4 wheel parts, southern Offroad and elite. I would trust elite over the others.

A 9 inch out of an explorer is a popular swap. It is the correct size. It is more to install because mounts will have to be fabricated. It, a lot of people use them.

Yeah with that tire setup 373s would be the best of both worlds imo. No if planning some 35s (or maybe even 33s) I'd go ahead and slap in the 4.11s.

Don't know much about Fords but I'd be shocked if Explores have 9" Diffs. My guess would be 8.8, big difference. A 9" is comparable to a Dana 60, some folks say even better, they are big and beefy. Irish doesn't need to get into housing swaps for his machine IMO.

Dang, you're right. I'm off my game lately.... The 8.8 out of the explorer is the popular swap for a TJ