Just trying to figure some things out and want to ask the group their thoughts on my recent differential pinion seal failure.
'87 325is with 107k original miles. The car is basically a SpecE30 build sans a full cage, kill switch and a few other odds and ends. I only use it currently for HPDE, but will eventually pull the roll bar for a full cage and go wheel to wheel with it.
Long and short, about a month ago I was replacing out the rear subframe with one with camber/toe adjustability. It's not a fun job, but in the end, everything went smoothly. During the process, I realized my driveshaft center support bearing was shot and upon inspection of the driveshaft, the rear u-joint was definitely not smooth. I bought a rebuilt unit from Driveshaft Specialist of Texas. The unit was perfect in every way (highly recommended). Also with the reinstallation of the subframe I used 75D AKG polyurethane subframe and diff mount bushings. Everything went together great.
A week later, I trailered the car to VIR to do an HPDE and the car ran flawless all weekend. I got it home, loaded it in the garage and it sat for about 10 days. At that point, I needed to move it to get something large in the garage. That's when I noticed the silver dollar size pool of gear oil. I then looked on the differential and it's coming from the front where the differential and driveshaft mate, signifying a pinion seal failure. There wasn't a drop of fluid on the trailer....
My question is do you think this is due to it being reasonably weak, but never leaking prior, and with the new driveline components, it killed it? When I replaced the driveshaft, which comes pre-balanced, I also installed it with a new OEM guibo as well, even though the one on there probably had less than 10k miles on it from looking at the condition.
It continues to seep, just sitting in the garage. My plan is to buy another used LSD diff, install that for the next event and completely rebuild this one over the winter. I'm just trying to figure out if there is something I'm missing here, or was this more coincidence than anything. Thanks for the advice in advance. - AB
'87 325is with 107k original miles. The car is basically a SpecE30 build sans a full cage, kill switch and a few other odds and ends. I only use it currently for HPDE, but will eventually pull the roll bar for a full cage and go wheel to wheel with it.
Long and short, about a month ago I was replacing out the rear subframe with one with camber/toe adjustability. It's not a fun job, but in the end, everything went smoothly. During the process, I realized my driveshaft center support bearing was shot and upon inspection of the driveshaft, the rear u-joint was definitely not smooth. I bought a rebuilt unit from Driveshaft Specialist of Texas. The unit was perfect in every way (highly recommended). Also with the reinstallation of the subframe I used 75D AKG polyurethane subframe and diff mount bushings. Everything went together great.
A week later, I trailered the car to VIR to do an HPDE and the car ran flawless all weekend. I got it home, loaded it in the garage and it sat for about 10 days. At that point, I needed to move it to get something large in the garage. That's when I noticed the silver dollar size pool of gear oil. I then looked on the differential and it's coming from the front where the differential and driveshaft mate, signifying a pinion seal failure. There wasn't a drop of fluid on the trailer....
My question is do you think this is due to it being reasonably weak, but never leaking prior, and with the new driveline components, it killed it? When I replaced the driveshaft, which comes pre-balanced, I also installed it with a new OEM guibo as well, even though the one on there probably had less than 10k miles on it from looking at the condition.
It continues to seep, just sitting in the garage. My plan is to buy another used LSD diff, install that for the next event and completely rebuild this one over the winter. I'm just trying to figure out if there is something I'm missing here, or was this more coincidence than anything. Thanks for the advice in advance. - AB
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