Diff leak

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808inthe949

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Hey guys, issue here. I recently replaced both cv axles and the axle seals but now Im having the passenger side leaking. It doesnt leak while just parked but does when I drive. Its not such a big leak that my diff fluid is low. when I remove the fill plug and stick my pinky in, the fluid is just below the point of coming out. I got the mopar seals and im fairly confident that I have the seals fully seated. I did not replace my intermediate shaft as I couldnt find one to purchase (other than one at $430 and 4 weeks shipping) but I am confident that it isnt damaged or worn as the diff wasnt leaking until after I changed my cv axles. My passenger side and drivers side cv axles have the same amount of slop (read play) so I hope the passenger side is fully installed in the diff. I did not change the "pinion seal" (sure thats not the right name) but would that cause a leak out of the passenger side right at that exterior seal?
Another possible cause is that when I filled the diff, the car wasnt level so maybe I over filled it and the extra is just leaking out? I checked the fluid when its level and it shows to be at the proper level even with the amount that has leaked out.
I am also using Valvoline full syn in both diffs. I have read that dyno is better but whats recommended?
 

tommudd

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Dino is better sticks to the gears better
As far as your leak, is it showing lots of fluid as in running/dripping or just damp looking
and cheapest Intermediate was how much ?
 

Aceofspades

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Think they are $108 now in the US. But I can attest that the seals I’ve got from that 4x4 site leaked day 3. Too lazy to pull it all apart again.
not sure what the “best brand” is or maybe a seal that wasn’t sitting on a shelf for 13 years lol
 

808inthe949

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Tom- which Dyno do you typically use? I do not have enough of a leak to have it drip down, after a 20m drive I can look under and there's a good coating on the lower control arm, the center cross member that supports the trans, and the housing that the passenger CV axle sits in just outside the long tube attached to the diff will have a little droplet hanging off but not actually dripping. When I check the fluid level it seems to still be full. The cheapest available one I found was $400+ and from Napa.
Ace- I got the seals from Morris4x4. I'm assuming that's the same one you did. I bought the Crown seals as they were supposed to be OEM. Leaked after the second or third day. Only from one side tho.
When looking for the intermediate shaft online, almost everywhere said it either wasn't available or on backorder from the manufacturer and would take weeks/months if it ever got shipped.
I wasn't able to dislodge the shaft from the passenger CV axle and trust me I tried. I even dropped it off at a machine shop to see if they could do it with their vices and such, no luck tho. Is there a trick or something? Could I have inserted the differential end of the shaft into the CV axle end (reversed the way it's supposed to go in) or are the splines different? If the clip on the end of the shaft were to be a little larger than original would it be harder to remove?
I had to cut my factory CV axle apart to remove the shaft from it (without damaging shaft since I couldn't find a replacement) and I inserted it into the new CV axle, installed the new seals, then reassembled everything, filled diff. Now that it's leaking I'd have to take that passenger side apart again and possibly have to buy a new CV axle for that side if I can't get the old shaft out. The spines looked really good with no visible damage, grooves still clean and not pitted or chunky, it wasn't even rusty (cars been in CA it's whole life). So I figured a good cleaning a little grease and it would be good to go
 

adamkrz

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If there enough play in the shaft ( worn bushing)it will leak even with a new seal, not sure about it with the jeep but my son's Honda civic leaked after replacing the cv half shaft even after multiple seal changes due to a worn bushing..
 

808inthe949

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Funny you mention that I was just under it this afternoon replacing my rack and pinion bushings (one was basically non existent, just the metal spacer) and I felt the slop or play in my CV axles.
Grabbed the inner housing on the driver's side and I get very little play in a rotational direction and also a little play in the in/out direction. I know the in/out is supposed to have play and I'm sure this is the correct amount.
Grabbed the passenger side inner housing and it has about twice as much slop in a rotational direction as the driver's side. Maybe even 2.5 times as much as the driver's side. It feels like it has the same play in/out as the driver's side or maybe just slightly more but not enough to be concerning.
What bushing would I be replacing to reduce the slop in that passenger side?
 
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