Front left different leak

At 150k my front left axle seal started leaking. Bad enough that there’s droplets at the bottom of the pumpkin. I replaced the seal two times but the leak isn’t even slowing down. The first time around I thought it was me, this second time around I made sure to install it by the book. The seal sits flush and I surgically installed the CV axle into the carrier . I should mention I’m not a rookie with this stuff so this isn’t my first rodeo. Technically the seal has 130k as I previously regeared the truck my self, and put new seals + the ECGS bushing in at the time. It’s been smooth sailing since, until now that is.

just to rule out the breather I popped the valve off the breather tube so it should be able to breath. No change.

I regret not taking a photo but I also didn’t think anything of it at the time. . Where the lip of the seal rides on the cv axle, the area was polished to a mirror finish and my nail could catch it.

So here’s a question, is it possible the area on the CV has worn down enough the seal can’t properly seal? I have never heard of this happening, but my finger nail could catch that surface, so I’m a bit suspicious.

any thoughts?

 

Might be caused by rust jacking in the diff case bore. Remove CV axle, remove seal, stuff the diff tube with a plastic bag, then clean up the seal seat area with a flap wheel. Only then install a new seal with some sealant on the OD.

 

Yup that’s gotta be it. I noticed some minor rust but didn’t want to fuck with it too much so I gently ran some scotch brite on it. What kind of sealant do you recommend?

 

Ultra gray? Right Stuff? The seal seat should be degreased with brake cleaner. You should also hold off refilling the diff until the sealant has cured. So pick a sealant with short curing time for schedule's sake.

 

Gotcha. I thought you meant a pipe dope or something similar. I understand what you mean

 

The groove on the CV shouldn’t catch a nail. If it is, then it probably is too sharp and is wearing out seals. I’d sand it down or replace the CV.

And maybe I’m misunderstanding, but the seal shouldn’t be installed flush. It should be recessed to a specific depth of something like 0.189”-0.229”

 

after a few of days of running it with the new seal and topping it off everyday the leak stopped. I’m not sure if the new seal needed to bed in, or if me not installing it 0.189-0.228” is allowing the seal to sit in a different spot.

anywho, I topped the fluid, went on a 400 mile round trip to an off-road event, abused the truck there and there’s still no sign of even a little seepage.

I’ll take the win, and will continue to monitor.

 

I was mistaken on the spec. The left side should actually be about flush. I could have sworn it followed the same spec as the right side but nope. Good that the leak stopped.