Replacing Oil Seal on Output shaft ?

2 replies to this topic
  • bfox55

Posted October 05, 2007 - 06:48 AM


I'm going to be replacing the output shaft oil seal tonight on my 99 400. My question is, Should I also replace the o-ring that is shown in this diagram behind the bearing? The Oil seal is part #25 the o-ring is #27. Is the bearing hard to pull? If not i'll probably go ahead and replace it while I'm in there but i'm assuming its pressed in. Thanks in advance for the help.
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  • grayracer513

Posted October 05, 2007 - 08:45 AM


The bearing can't be changed without splitting the cases, so yes, I'd say it's hard to pull.

The seal is easy. The collar that the seal rides on (#26 in the drawing) must be removed to get at the O-ring. Once the collar is off, you can use a small hooked pick to pull the ring out.

The collar can be a little stubborn sometimes if it sticks to the O-ring. If that's the case, put a punch in the center of the output shaft and give it a couple of taps with a hammer to move it back into the bearing a little, and that will break the adhesion on the O-ring. Then, with the trans in gear, you can grab the end of the collar and rotate and pull it at the same time to remove it.

The collar itself should be inspected for the presence of a significant groove worn in by the seal. If it has one that will catch a fingernail, the collar should be replaced to keep it from causing the new seal to fail.

The ring under the collar is not usually the source of a leak, so you could leave alone and maybe be safe. Your call on that.

  • bfox55

Posted October 05, 2007 - 09:42 AM


Thanks alot for the help. I'll just replace the seal for now and see if that fixes my leak.

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