Novak Conversions Jeep Wrangler TJ radiator

Rear differential solutions

AWC4216

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Jul 6, 2019
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NW Georgia
Looking for some advice.

I have a 99 Sahara on 33's, 4.5" suspension lift, 1" body lift with Dana 35.

I was attempting to teach my wife to drive a stick Thursday evening, she kind of held the brake while letting off the clutch, then pop goes the rear diff. (Not her fault or anything, that's just what happened and could have easily happened driving it anywhere else).

If I had my guess, my ring gear is probably missing some teeth. I haven't had it but a little over a month. Bought it built, so I really don't know what kind of off-roading it experienced before me. Judging by the cleanliness of the engine bay and everything underneath, probably not a lot. I think it accrued more hwy miles than anything. I'm not looking to be a heavy off-roader, but if I wouldn't mind having that capability in my back pocket.

Anyways, I don't have the resources/knowledge to do any of the repair, and got to looking at previous threads about the ford 8.8.

Should I expect about the same (cost-wise) to have new gears, if that is what my issue is, compared to finding a Ford 8.8 with the same gear ratio and having someone do the swap for me?
I've found some on craigslist and car-parts.com from about $120-300. How much more for mounting brackets/kit? Or would it be more expedient to hit the guy up from SFF customs in Colorado for one he has rebuilt for $1200?

This is all new to me, so any help would be appreciated. Thanks!

Also, anyone in the Rome, GA/Chattanooga area with recommendations for a shop or person to work on this would be awesome.
 
I side with the camp that says avoid the 8.8.

Since it's just the differential, the smart thing to do IMHO would be to install a Revolution Super 35 kit, re-gear it at the same time, and put in a selectable locker.

That could typically be done for cheaper than an 8.8, and a Super 35 is more than capable of running 35" tires, even in very tough terrain.

See this thread here:
Should I upgrade my Dana 35 axle?
 
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First off, welcome to the forum.

Next, do you have the ability to pull the cover and take a look inside? Maybe post up some pics. That would be the first thing I'd recommend before jumping into a 8.8 conversion.
 
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First off, welcome to the forum.

Next, do you have the ability to pull the cover and take a look inside? Maybe post up some pics. That would be the first thing I'd recommend before jumping into a 8.8 conversion.
X2, find out what broke before deciding what to do. One of the axle shafts just might have snapped which is a relatively easy repair. And no matter what happened the last thing I'd do is to replace the axle with an 8.8.
 
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I side with the camp that says avoid the 8.8.

Since it's just the differential, the smart thing to do IMHO would be to install a Revolution Super 35 kit, re-gear it at the same time, and put in a selectable locker.

That could typically be done for cheaper than an 8.8, and a Super 35 is more than capable of running 35" tires, even in very tough terrain.

See this thread here:
Should I upgrade my Dana 35 axle?

I think my TJ's ratio is 3.55. Which would be an optimal regear ratio?
 
Just FYI, the only year to use 3.55 axle ratio was 1997.
That's good to know, but it's not stock. The previous owner rebuilt the back end. I want to say he told me 3.55, but I may have misheard. I suppose I'll be getting in touch with him to go over it again.
 
That's good to know, but it's not stock. The previous owner rebuilt the back end. I want to say he told me 3.55, but I may have misheard. I suppose I'll be getting in touch with him to go over it again.
Well, if he rebuilt the back end, he would have had to do the front also, if he ever wanted to put it in 4wd. The front diff would have 3.73 gears. Unless he changed those also. Hard to imagine regearing from 3.73 to 3.55.
 
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Well, if he rebuilt the back end, he would have had to do the front also, if he ever wanted to put it in 4wd. The front diff would have 3.73 gears. Unless he changed those also. Hard to imagine regearing from 3.73 to 3.55.
It’s amazing how much one can learn on the internet lol. Thanks!
 
What you currently have doesn't really matter if you are changing gear ratios anyway, except if a new carrier is needed.
 
X2, find out what broke before deciding what to do. One of the axle shafts just might have snapped which is a relatively easy repair. And no matter what happened the last thing I'd do is to replace the axle with an 8.8.
What's all the hate on 8.8 ( made a rhyme ) I thought a few years ago that was one of the big things. Dump the Dana 35 and transplant in a 8.8 or a Dana 44. Is it because of the Super 35 kits ? Curious minds want to know ?
 
The 8.8 was, for a while, a popular swap but it no longer is. It's more work and costs more to convert an 8.8 to work in a Wrangler TJ than most were aware. Then it's also narrower than the OE axles are, its pumpkin is huge and reduces ground clearance, and its pinion is offset to the side which makes the rear driveshaft work into a compound angle of both up & down plus side-to-side.
 
If you can get the 8.8 cheap enough and swapped in for cheaper than the Super35 ($1200+-)it might be beneficial to you.

Weigh your pros and cons. IIRC only the Rangers and Explorers came with 5x4.5 bolt pattern axles (matches the TJ/LJ)

They are a bit narrower (how much? .950 inches) narrower rear ends are ideal.

Not all 8.8’s have offset pinions.

Pumkin is bigger because the 8.8 ring gear and pinion is bigger. 🤔

https://wranglertjforum.com/threads/ford-8-8-axle-swap-info-faq.66/
 
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Don't concern yourself with the ratio or full on swaps at the moment. My best guess would be the spider gears are grenaded, very common on the 35. Those are cheap and easy to swap out, a total diy in your driveway. I think I still have my set from my rebuild. Almost new and you can have them for shipping cost. Again, pull the cover and take a look.
 
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Novak Conversions Jeep Wrangler TJ radiator