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| | | | Joined: Oct 2010 Posts: 32 Wrench Fetcher | | Wrench Fetcher Joined: Oct 2010 Posts: 32 | Took it to a transmission/diff shop. They managed to fix the two speed vacuum shift, but said they couldn't identify a replacement for the differential pinion seal.
He said if we are replacing the differential pinion seal it may make sense to replace the pinion flange as well.
So how can I find replacements? I've went to napa and my better parts store, monument, and none of their books cover the 2 ton. They can usually find the ones for the 1/2 tons.
Any help is appreciated.
| | | | | Joined: May 2005 Posts: 8,878 . | | . Joined: May 2005 Posts: 8,878 | Pull the seal and measure it (or more accurately the shaft and bore), then I bet NAPA does have one.
Grigg | | | | | Joined: Nov 2005 Posts: 6,100 'Bolter | | 'Bolter Joined: Nov 2005 Posts: 6,100 | Hy donnoman, is this seal for your 57 Chevy 6100 wrecker? If your diff. is an Eaton the seal p/n is National 411330N, if it is the corporation diff. (Salisbury) the seal p/n is National 5M89, hope that helps. | | | | | Joined: Oct 2010 Posts: 32 Wrench Fetcher | | Wrench Fetcher Joined: Oct 2010 Posts: 32 | Thanks guys, yah was trying to have replacement avail before tearing apart the diff.
3B yes, it is for my 6100 wrecker, Is there a way to identify on the axle/diff if it's an Eaton or corporation?
I would think Eaton would have made it easier to identify, so I'm leaning towards the corp.
Last edited by donnoman; 10/19/2012 12:58 AM.
| | | | | Joined: Jan 2008 Posts: 4,962 'Bolter | | 'Bolter Joined: Jan 2008 Posts: 4,962 | Either Eaton or Rockwell made the 2 speeds for GM. The smaller ones like yours would be an Eaton. | | | | | Joined: Nov 2005 Posts: 6,100 'Bolter | | 'Bolter Joined: Nov 2005 Posts: 6,100 | Hy donnoman, the Eaton diffs. are round, the corporation diffs have a flat on the top and bottom if I am remembering correctly. 5M89 is actually a felt seal not a steel encased seal that we normally think of. As Grigg said once you know the dimensions of the seal required there is more than likely one out there to fit, hope that helps. | | | | | Joined: Sep 2001 Posts: 29,270 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,270 |
donnoman,
If it is a 411330N seal, I'll send you one as a gift. It is readily available from Rockauto.com
PM me and give me your phone number and address.
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