Trying to understand my rear differentials

I read somewhere that someone had a TJ that had a Dana 44 housing with a Dana 35 axle. They said the factory ran out of Dana 35 housings and they added extra shims at the factory and used the Dana 44’s on some builds. Not sure if there is any truth to this or not, but it could explain it!
 
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Make sure the pinion is good and pick up a new ring gear. It’s an easy swap, just remove it from the carrier and put the new one on. Torque to spec
 
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I read somewhere that someone had a TJ that had a Dana 44 housing with a Dana 35 axle. They said the factory ran out of Dana 35 housings and they added extra shims at the factory and used the Dana 44’s on some builds. Not sure if there is any truth to this or not, but it could explain it!
Possibility, so it looks like I'm geared correctly front to back which is a relief, now to the question what's the best/cheapest way to fix it, I was thinking if I have to relive the shafts the I may as well replace every bearing and seal from one hub to another anlong with all the U joints, but this vehicle just sits out side my house as I work from home and mainly ride motorbikes when I fell like escaping, so is it really worth replacing/totally rebuilding the diff, especially when everything around it seems so nice and tight ?
 
Possibility, so it looks like I'm geared correctly front to back which is a relief, now to the question what's the best/cheapest way to fix it, I was thinking if I have to relive the shafts the I may as well replace every bearing and seal from one hub to another anlong with all the U joints, but this vehicle just sits out side my house as I work from home and mainly ride motorbikes when I fell like escaping, so is it really worth replacing/totally rebuilding the diff, especially when everything around it seems so nice and tight ?
You do not have to touch the barrings. The ring gear is bolted on the carrier. You just need a ring gear.

Remove axles
Remove carrier
Unbolt ring gear
Bolt on new ring gear
Intall carrior
Install axle.

That is the cheapest way to go. If you wanted to be extra safe you can replace the pinion gear also with a matched set.
 
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Possibility, so it looks like I'm geared correctly front to back which is a relief, now to the question what's the best/cheapest way to fix it, I was thinking if I have to relive the shafts the I may as well replace every bearing and seal from one hub to another anlong with all the U joints, but this vehicle just sits out side my house as I work from home and mainly ride motorbikes when I fell like escaping, so is it really worth replacing/totally rebuilding the diff, especially when everything around it seems so nice and tight ?
I would repair as @JMT and @Boinked eplained. Seems easy enough. Curious...what symptoms/noises do you have, if any, when driving?
 
I read somewhere that someone had a TJ that had a Dana 44 housing with a Dana 35 axle. They said the factory ran out of Dana 35 housings and they added extra shims at the factory and used the Dana 44’s on some builds. Not sure if there is any truth to this or not, but it could explain it!
Possibility, so it looks like I'm geared correctly front to back which is a relief, now to the question what's the best/cheapest way to fix it, I was thinking if I have to relive the shafts the I may as well replace every bearing and seal from one hub to another anlong with all the U joints, but this vehicle just sits out side my house as I work from home and mainly ride motorbikes when I fell like escaping, so is it really worth replacing/totally rebuilding the diff, especially whe
You do not have to touch the barrings. The ring gear is bolted on the carrier. You just need a ring gear.

Remove axles
Remove carrier
Unbolt ring gear
Bolt on new ring gear
Intall carrior
Install axle.

That is the cheapest way to go. If you wanted to be extra safe you can replace the pinion gear also with a matched set.
Thanks for that info it's appreciated, how dose this pinion look I thought it looked quite work and is definitely scratched/scored in place's, is the gap between the pinion and ring gear teeth normal ? Or dose this have something to do with why I broke a tooth ? There seems to be zero play in the pinion bearing and it's totally dry
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Possibility, so it looks like I'm geared correctly front to back which is a relief, now to the question what's the best/cheapest way to fix it, I was thinking if I have to relive the shafts the I may as well replace every bearing and seal from one hub to another anlong with all the U joints, but this vehicle just sits out side my house as I work from home and mainly ride motorbikes when I fell like escaping, so is it really worth replacing/totally rebuilding the diff, especially whe

Thanks for that info it's appreciated, how dose this pinion look I thought it looked quite work and is definitely scratched/scored in place's, is the gap between the pinion and ring gear teeth normal ? Or dose this have something to do with why I broke a tooth ? There seems to be zero play in the pinion bearing and it's totally dry View attachment 51849 View attachment 51850
You should have some play, as you rotate the driveshaft by hand it should delay and then engage both directions. You can’t tell by looking if the backlashing is correct. You have to buy some gear paint at Napa or whatever you’ve got, paint 5 or 6 teeth and rotate the driveshaft under simulated load and look at the pattern.
upload_2018-8-18_8-55-3.gif
 
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You should have some play, as you rotate the driveshaft by hand it should delay and then engage both directions. You can’t tell by looking if the backlashing is correct. You have to buy some gear paint at Napa or whatever you’ve got, paint 5 or 6 teeth and rotate the driveshaft under simulated load and look at the pattern.
View attachment 51854
Appreciate the post, I think my next move from here is to have my guy who will be fixing it look at it, Im very capable with everyday stuff but internals of gearboxes and diffs aint anything I've ever had the pleasure with so will have to pass it over
 
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Appreciate the post, I think my next move from hear is to have my guy who will be fixing it look at it, Im very capable with everyday stuff but internals of gearboxes and diffs aint anything I've ever had the pleasure with so will have to pass it over
Good move. If something is wrong in the backlashing, and it sounds like it is if you have no play, then what you’re essentially having done is a regear. In that case, I’d use it as an opportunity to upgrade your gears in both axles. Decide what your largest tire you’ll run will be, tell us what transmission and engine you have, and there will be a good suggestion. No use spending all that dough to fix 3.07’s. Even if your friend is just helping you for free, it’s not worth the work. And yes, you can do the inner seals while you’re there
 
Good move. If something is wrong in the backlashing, and it sounds like it is if you have no play, then what you’re essentially having done is a regear. In that case, I’d use it as an opportunity to upgrade your gears in both axles. Decide what your largest tire you’ll run will be, tell us what transmission and engine you have, and there will be a good suggestion. No use spending all that dough to fix 3.07’s. Even if your friend is just helping you for free, it’s not worth the work. And yes, you can do the inner seals while you’re there
I was thinking about regearing but that's going to double the cost, plus I've just moved to brand new slightly bigger tyres ressiting spending loads, this truck will probably do 1000 to 1500 miles a year so sadly I just cant get involved in the whole out of control 4X4 thing (even though I want to lol ) so throwing loads of cash at is just isn't an option
 
I read somewhere that someone had a TJ that had a Dana 44 housing with a Dana 35 axle. They said the factory ran out of Dana 35 housings and they added extra shims at the factory and used the Dana 44’s on some builds. Not sure if there is any truth to this or not, but it could explain it!
If so, would the the Dana 35 27 spline carrier work with the Dana 44 30 spline shafts? Or would the Dana 35 shafts work on the Dana 44 housing without retainer plates? I doubt this ever happened. Seems more cost effective to just install a full Dana 44 rather than a cobbled together hybrid.
 
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I was thinking about regearing but that's going to double the cost, plus I've just moved to brand new slightly bigger tyres ressiting spending loads, this truck will probably do 1000 to 1500 miles a year so sadly I just cant get involved in the whole out of control 4X4 thing (even though I want to lol ) so throwing loads of cash at is just isn't an option
IF there is no play, such that your pinion is to deep into the ring gear, indicating improper backlashing, and you just replace the ring gear, it will likely just break another tooth. IF NOT, and the backlash is good, just replace the ring gear. That's your cheapest option ($250 DIY, not difficult). The next cheapest option is to rework the gearing on the Dana 44 so the backlashing is correct ($250 + labor, probably $500 = ~$750.) Most expensive is to re-gear both diffs (~$1500).
 
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You do not have to touch the barrings. The ring gear is bolted on the carrier. You just need a ring gear.

Remove axles
Remove carrier
Unbolt ring gear
Bolt on new ring gear
Intall carrior
Install axle.

That is the cheapest way to go. If you wanted to be extra safe you can replace the pinion gear also with a matched set.

Uh, no. You need a matched/lapped set. You cannot just change one or the other.

Don't get too caught up in "what should be installed." Remember, he is in the UK, so who knows what the standard over there were.

You need a new gear set plain and simple. It needs to be set up by a pro with new bearings and seals. The other option is to find a used one in good shape, good luck with that being a 44.
 
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Uh, no. You need a matched/lapped set. You cannot just change one or the other.

Don't get too caught up in "what should be installed." Remember, he is in the UK, so who knows what the standard over there were.

You need a new gear set plain and simple. It needs to be set up by a pro with new bearings and seals. The other option is to find a used one in good shape, good luck with that being a 44.

When you are borke as hell and need to get running you CAN replace just the ring.
Will it lost as long as doing everything ....hell no.
Replacing just the ring is not the best option. But alot of people cant just drop a crap ton of money into thier jeep.
Then you have to look at the other side of it. If he is saving money to regear both why drop the money into a set of 3.07s when in time he will just be changing them out.
If he goes down to the junkyard and finds a 3.07 ring gear it will be close enough to work until he can afford a proper gear change.
 
When you are borke as hell and need to get running you CAN replace just the ring.
Will it lost as long as doing everything ....hell no.
Replacing just the ring is not the best option. But alot of people cant just drop a crap ton of money into thier jeep.
Then you have to look at the other side of it. If he is saving money to regear both why drop the money into a set of 3.07s when in time he will just be changing them out.
If he goes down to the junkyard and finds a 3.07 ring gear it will be close enough to work until he can afford a proper gear change.

Running a mismatched gear set is a very bad idea. If they even mesh up at all, they aren't going to last. Depth and backlash are dependent on many things inside the differential two of which are the cuts on the ring and pinion. You are giving bad advice and should stop.
 
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When you are broke as hell and need to get running you CAN replace just the ring.
No, you cannot just replace the ring gear. Ring & pinion gears come as matched sets and not only would they be different enough from even the same brand so it should be not done, they wouldn't even be close with another brand of gear.
 
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Uh, no. You need a matched/lapped set. You cannot just change one or the other.

Don't get too caught up in "what should be installed." Remember, he is in the UK, so who knows what the standard over there were.

You need a new gear set plain and simple. It needs to be set up by a pro with new bearings and seals. The other option is to find a used one in good shape, good luck with that being a 44.
So replacing the ring gear and pinion, pinion bearing and seal isn't a good idea on its own ? Are you saying I should replace all the moving parts in the casing completely?
 
So replacing the ring gear and pinion, pinion bearing and seal isn't a good idea on its own ? Are you saying I should replace all the moving parts in the casing completely?
Not at all. If the carrier bearings look good, that would be the best and most economical way to go. So, ring and pinion, pinion bearings and seal, possibly carrier bearings, possibly axle bearings and seal.
 
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