How To Fix A Leaking GM 12-bolt Rear-end Pinion Seal

via Hagerty DIY ~ Here is the ONLY WAY to fix a leaking GM 12-bolt differential pinion seal…

Does your rear differential leak gear oil everywhere? Do you keep installing a new pinion seal and having the same problem? Everyone has or will have this problem when installing a new pinion seal in your 12-bolt GM rear differential, but Hagerty’s Davin Reckow is here to help.

GM made two different versions of the 12-bolt rear end: one for trucks and one for cars. This means two different pinion seals. Unfortunately, the car version of the seal has been discontinued, and the truck version is the only one still available.

Even if you walk into your local parts store and tell them it’s for your Chevelle or Camaro or Impala, the one they’ll have is the truck version. Most shops don’t even know there was a difference.

The solution to this problem is installing the available truck version of the pinion seal using a spacer or leaving a gap. This is the only way to ensure a quality seal with the yoke.

Watch the video, solve your leaky rear differential problem, and maybe even be the hero and your next local Cars & Coffee…