Pinion seal leak, the never ending bad tooth.
06-16-2013, 08:26 AM
#1
Pinion seal leak, the never ending bad tooth. As most of you know I trackday this car in HPDE events and it is a full blown street car.
A year ago I rebuilt the rear with new bearings and seals due to a bad carrier bearing on the Power Tour. Made the pinion leak even worse than it was.
I put a new GM yoke kit in it, stopped leaking for a short time, then right back to seeping, and now back to a bad leak AGAIN.
12 bolt or nine inch will not happen, I have no reason to spend $3k on a rear that I dont need.
Is a solid pinion spacer the fix? If not what is? I can manage the seep, but the fluid all over the exhaust etc I can't do.
The GM engineer who approved this rear for this car should have had one dropped on his head from a 3 story building, what a PITA.
A year ago I rebuilt the rear with new bearings and seals due to a bad carrier bearing on the Power Tour. Made the pinion leak even worse than it was.
I put a new GM yoke kit in it, stopped leaking for a short time, then right back to seeping, and now back to a bad leak AGAIN.
12 bolt or nine inch will not happen, I have no reason to spend $3k on a rear that I dont need.
Is a solid pinion spacer the fix? If not what is? I can manage the seep, but the fluid all over the exhaust etc I can't do.
The GM engineer who approved this rear for this car should have had one dropped on his head from a 3 story building, what a PITA.
06-16-2013, 10:10 AM
#2
Here is some info I was given on this subject, maybe it will help you out.
"Your rear end pinion seal leak is very common. Replacing the pinion seal only will not fix the problem. The leak will come back in time, in some cases the next day. The real problem with the 7.5 and 7.625 rear ends is the yoke. The diameter of the journal where the pinion seal rides on the yoke is too small. In 2002, an updated yoke was released with a collar pressed on the yoke to enlarge the diameter of the journal. Also, a new seal was made available to work with the yoke. GM lists the yoke and seal, but it must be ordered for a 2002 Trans Am. I bought my seal from GM and the yoke that is made by AAM who makes it for GM. Shortly after I bought my car in 2007, my pinon seal started to leak. I changed the gears to 4.10:1 and updated the yoke and seal. After 70,000 miles, there is absolutely no sign of a leak - dry just like new. This is the ONLY permanent fix for the leak."
Hope that helps, and maybe someone else can confirm this.
"Your rear end pinion seal leak is very common. Replacing the pinion seal only will not fix the problem. The leak will come back in time, in some cases the next day. The real problem with the 7.5 and 7.625 rear ends is the yoke. The diameter of the journal where the pinion seal rides on the yoke is too small. In 2002, an updated yoke was released with a collar pressed on the yoke to enlarge the diameter of the journal. Also, a new seal was made available to work with the yoke. GM lists the yoke and seal, but it must be ordered for a 2002 Trans Am. I bought my seal from GM and the yoke that is made by AAM who makes it for GM. Shortly after I bought my car in 2007, my pinon seal started to leak. I changed the gears to 4.10:1 and updated the yoke and seal. After 70,000 miles, there is absolutely no sign of a leak - dry just like new. This is the ONLY permanent fix for the leak."
Hope that helps, and maybe someone else can confirm this.
06-16-2013, 10:24 AM
#3
Here is some info I was given on this subject, maybe it will help you out.
"Your rear end pinion seal leak is very common. Replacing the pinion seal only will not fix the problem. The leak will come back in time, in some cases the next day. The real problem with the 7.5 and 7.625 rear ends is the yoke. The diameter of the journal where the pinion seal rides on the yoke is too small. In 2002, an updated yoke was released with a collar pressed on the yoke to enlarge the diameter of the journal. Also, a new seal was made available to work with the yoke. GM lists the yoke and seal, but it must be ordered for a 2002 Trans Am. I bought my seal from GM and the yoke that is made by AAM who makes it for GM. Shortly after I bought my car in 2007, my pinon seal started to leak. I changed the gears to 4.10:1 and updated the yoke and seal. After 70,000 miles, there is absolutely no sign of a leak - dry just like new. This is the ONLY permanent fix for the leak."
Hope that helps, and maybe someone else can confirm this.
"Your rear end pinion seal leak is very common. Replacing the pinion seal only will not fix the problem. The leak will come back in time, in some cases the next day. The real problem with the 7.5 and 7.625 rear ends is the yoke. The diameter of the journal where the pinion seal rides on the yoke is too small. In 2002, an updated yoke was released with a collar pressed on the yoke to enlarge the diameter of the journal. Also, a new seal was made available to work with the yoke. GM lists the yoke and seal, but it must be ordered for a 2002 Trans Am. I bought my seal from GM and the yoke that is made by AAM who makes it for GM. Shortly after I bought my car in 2007, my pinon seal started to leak. I changed the gears to 4.10:1 and updated the yoke and seal. After 70,000 miles, there is absolutely no sign of a leak - dry just like new. This is the ONLY permanent fix for the leak."
Hope that helps, and maybe someone else can confirm this.
I already did this.
06-16-2013, 12:00 PM
#4
Come to think of it, I installed this complete GM yoke kit as delivered. It went from leaking to POURING.
I pulled it back out, drove the sleeve of the yoke, installed with the first gen seal and it was good for a while.
No parts house has the second gen seal, all the list is the first or if it does list it it really is no different from the first design seal.
SO I am bout to put ANOTHER first design seal in to slow it down till I can get a plan of action.
May do a solid spacer with a new GM second design seal.
I pulled it back out, drove the sleeve of the yoke, installed with the first gen seal and it was good for a while.
No parts house has the second gen seal, all the list is the first or if it does list it it really is no different from the first design seal.
SO I am bout to put ANOTHER first design seal in to slow it down till I can get a plan of action.
May do a solid spacer with a new GM second design seal.
