Pinion seal woes

[Vermonter]

Hi all,
In Aug 2001 I bought a 99 MM with the 5.0 V8 with 29k on it. Since then I have changed the pinion seals multiple times. At 33k I replaced the front seal. At 53k I replaced the front seal again. I replaced front and rear seals at 72k, and finally at 96k I just replaced front and rear seals again. Does this seem a little excessive? What could cause the seals to wear and leak so quickly? Thanks

 

[IZwack]

That is excessive. The first time my 98 XLT had both of its pinion seals replaced was at around ~120k miles.

One reason as to why a pinion seal might wear out prematurely is that the pinion bearings/races are dead - causing play in the pinion which then wobbles and damages the seal.

 

[Vermonter]

I went back to the shop and asked them why I've gone through so many seals and they think that it is normal They tell me that they always check the flange for grooves, and will gladly open it up for further inspection if I pay. Why they didn't dig further while in for other work I don't know... Unless they are looking for more money. Nah

 

[Vermonter]

Update!

Well I found out why I was going through seals...the right side pinion gear set up is trashed so I'm sure that made the seals wear prematurely. I started feeling a vibration that came and went as I drove, so I had a different shop check it out and voilà.

As luck would have it though, when the shop pulled off the rotors they said that the guy that did my recent rear brake job had failed to back off the e-brake and when he pulled off the rotors to replace 'em he snapped off the e-brake pads. They'll put on a new set labor free since they are working on the axles anyway, I just have to pay for the pads ($135). It's a he said she said situation on who exactly broke them, so it looks like I'm on the hook for the repair. I guess thats the price ya pay sometimes if you don't do the work yourself

 

[IZwack]

Well I found out why I was going through seals...the right side pinion gear set up is trashed so I'm sure that made the seals wear prematurely.

I dont quite understand - there is only one pinion gear per axle - no right/left.

 

[Vermonter]

I dont quite understand - there is only one pinion gear per axle - no right/left.

I guess when I was seeing red I wasn't listening well enough when he told me what the axle problem was. I was too focused on the e-brake issue. I do remember him saying right side and pinion gear, so I'm guessing that maybe the end of the axle and maybe the pinion gear are bad.

I had (expired yesterday) an extended warranty so at least I'm only out the $100 deductible for this last covered repair. On Monday I'll find out exactly what the problem was and post back.

 

[Vermonter]

Further developments

Well I got the MM back from the shop and good news is... I have a rebuilt rear end (carrier bearings & races, pinion bearings & races, right axle shaft) minus the left axle shaft and e-brakes now. Bad news is... the warranty is up and there is still a vibration which the shop "thinks" it is a transfer case issue. the shop balanced all four tires, took each drive shaft out individually and stopped there. Because i did the 60k service a tad late, the warranty company refuse to pay for any TC repairs. Lesson learned here

My uneducated guess is...the wobbling cause by the slop in the rear end has ruined something in the TC. Course with my luck the tranny could be the culprit after some of the fluid leaked into the TC from a bad seal (replaced 1,300 miles ago). The vibration I feel is at speeds above 35mph and gets faster as speed increases. It isn't a violent vibration, more of a roughness in the driver train. Anyone with suggestions, thoughts ,ideas?

 

[David Suesz]

That's about $100 more than those

shoes should cost you. Advance Auto lists six different grades & brands of rear e-brake shoes, from $16-$49.