Replacing front axle seals, installing new hubs and bearings, and replacing the front hub u-joints.

Firstjeepbuild

Firstjeepbuild

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I have a 1999 Jeep TJ with the 4.0 and 3 speed automatic. I am looking at Rock auto and other sites for all the parts but there are several choices what are good hubs ,axle seals and U-Joints to replace my 24 year old ones. I dont do rock crawling I am mostly in the desert and a little mountain 4 wheeling while hunting . I don't mind spending more for better parts but don't want up waste it on over priced stuff. Thanks
 
Absolutely go with the Spicer 5-760x u-joint for the axle shafts. That's the u-joint Spicer designed specifically for the then still under development TJ Rubicon at Jeep's request. It's a stronger and more durable direct replacement for the base level Spicer 297 u-joint the factory installed on non-Rubicons.
 
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You'll need to take a front rotor off and measure it because it's a 99. There was a mid year change that will determine if you need a 97-99 hub or 00-06 hub. Once the rotor is off set it face down so it's orientated like a bowl. Then take something flat across the top side (it needs to be flat, a warped 1x2 isn't the call here). Then use a tape measure or ruler and measure the distance from the inside surface where the hub will seat to the bottom of your straight object. The two possible results are 2-3/4" or 3". If its 3" you need the older style, if its 2-3/4" you need the newer style. I'll link the hubs and u-joints below

Spicer 5-760X U-joint

Timken Hub for 00-06, 2-3/4" result

Timken Hub for 97-99, 3" result
 
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I also saw you said seals, the only real seal is just outboard of the carrier bearings and requires removal of the carrier to replace. If they aren't leaking I'd leave them unless you're doing a regear/locker install/ something where you're in there already. If you mean the black disks on the axle the sit against the end of the tube they're just dust shields and don't really matter. Do not buy those "seals" that have like 3 o-rings and go in the end of the tube with a zerk fitting. They're a total waste of money and do way more harm than good.

If I got those for free I'd still have buyers remorse.
 
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Foxhound67 said:
I also saw you said seals, the only real seal is just outboard of the carrier bearings and requires removal of the carrier to replace. If they aren't leaking I'd leave them unless you're doing a regear/locker install/ something where you're in there already. If you mean the black disks on the axle the sit against the end of the tube they're just dust shields and don't really matter. Do not buy those "seals" that have like 3 o-rings and go in the end of the tube with a zerk fitting. They're a total waste of money and do way more harm than good.

If I got those for free I'd still have buyers remorse.
Click to expand...

Totally agree on no aftermarket axle tube seals, but a differing opinion on the “real” axle seals. With the shafts already out, I think I would pop the diff cover off, pull the carrier, and replace the (possibly 24 yr-old) seals. Unless he knows that they have been replaced relatively recently.
 
rouxbicon said:
Totally agree on no aftermarket axle tube seals, but a differing opinion on the “real” axle seals. With the shafts already out, I think I would pop the diff cover off, pull the carrier, and replace the (possibly 24 yr-old) seals. Unless he knows that they have been replaced relatively recently.
Click to expand...

He doesn't say what rear end he has, but if it's a 44 then I think I would disagree with you on the seals. Sure you've got the axles out, but to replace the seal now you're talking about draining the gear oil, new gasket or the hassle of RTV (whichever you prefer), plus pulling the carrier and potentially dealing with the shims.... All to replace a seal that doesn't show any evidence of needing to be replaced. Or maybe I'm just cheap and get annoyed by how expensive gear oil is. If you were already due to change out the diff oil, then my answer probably changes.

On the other hand if it's a 35 he has to open the diff anyway for the c clips.
 
I assumed he was talking about the front because of the u-joints. If it's front and rear I don't think my opinion changes. Leave the seals be unless they're leaking or you have to go in there anyway.
 
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Sorry it’s the front on a stock dana 30 , the seals are leaking and the passenger side wheel bearing is bad.

Thanks Foxhound67 for the hub insight.

I was going to drop the tie rod on the drivers side to remove the carrier but from the write up it does not look like i need to. Is it worth dropping the drivers side of the tie rod or is that just extra work for nothing ?
 
When I did mine I put the front up on jack stands on the forward section of frame and let the axle droop, it cleared enough that way that I didn't have to remove the tie rod.
 
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After taking the front end apart I see the ball joints are loose and one of the differential bearings is pitted. The gears look great. I assume Timken bearings are good unless someone has reason to get something else. Is it worth it to get the heavy duty ball joints ? Picture of the one bearing attached.

71573289677__7D954B5A-E279-4AF1-95FB-7768A568A7EC.jpeg
 
I would go with Timken on the bearings for sure, but what I don't know is if you can simply replace those bearings of if you need to re-check backlash etc & potentially need to re-shim and all that. If you can just replace the bearings then I would replace it with exactly what was already on there to simplify your life.
 
Probably but I would get some gear paint...or a paint pen and run a pattern.

Almost makes me want to tell you to check the pinion bearings.

-Mac
 
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