Hey everyone I am in need of a bit of knowledge/assistance. I have a 72 Cutlass and for the life of me I can not find any type of stampings on the axle to identify it. I am quite certain it is the standard "corporate" axle that was used in 72. I noticed yesterday that the right rear axle seal was leaking. Pulled the wheel and brake drum to confirm and it was definitely gear lube leaking not the wheel cylinder. My first question is can you help identify this rear end by the photos? Second, can you help me confirm the parts needed to repair the leak? I was first thinking the seal would be in the tube but it appears to be pressed in with the bearing on the axle. I do have the CSM and will be using this to follow step by step replacement procedures but for me it always helps to hear it from seasoned professionals like you all on this site. I have never gotten into a differential type repair so I want to make sure I do this correctly. Unfortunately since I'm in Ohio after this she'll be going into hibernation mode for the next few months. Just looking to get this resolved before she goes to rest for a while.





Mike

 

There should be a stamping on the passenger side axle tube facing towards the front of the car. You should see something similar to this.

 

Thanks for the help. Evidently there was plenty more grease than I thought lol. I was able to find what appears to be SA B 239 2

 

That appears to be a corporate 8.5” 10 bolt. Pictures of the side and front of the center section would confirm that. There’s a casting number on the lower front part of the center section that would be the definitive identification. The 71-72 Olds version had a block O as seen in the picture below.

Note that the bearing race is still in the end of the tube.

Should be a Timken Set9 bearing. I don’t remember the seal part number, but monzaz has posted quite a few times about one seal that is too thin and results in excessive axle end play.

edit: I found this from monzaz:
712146 SEAL IS SUPPOSE TO MEASURE .490

 

Thanks for the information! I don't have the ability to press these on so I'll be looking to source that out.

 

Make sure they press the bearing on in the correct orientation. Some have been installed backwards and resulted in excessive end play. Use your picture above for reference.

Also make sure they press the bearing on correctly and don’t ruin the race as in this post:

https://classicoldsmobile.com/forums...rrectly-82968/


Here’s some info from a post by monzaz showing the correct bearing orientation:


https://classicoldsmobile.com/forums...arings-174482/

 

I was able to get the seal and bearing all pressed and the axle is back in. I decided to change the differential fluid while I was in there so I've got the new gasket sealing overnight before I refill. Tomorrow is quite busy for me so I hope to have her on the road Friday as it's just about time to put her away for the winter.