What is the best tool to use to install new pinion seal in 8.75 (741 case)? I removed the old seal and had the correct new seal in hand. Tried using a block of wood to persuade it to go in. Took my time and was moving the block of wood around the outside but the fit was very tight. I managed to get it seated but the outer lip was obviously damaged. I believe I actually managed to make the leak worse. Have new seal on order but I'm convinced there is a better tool to use for install. I just need help in identifying that tool. Thanks.

I use a section of pvc pipe that's the correct diameter (I think it's a joint type peice). Works great.

Also be sure to RTV around the seal to the case, even though it appears to have a bead on it.

clean the ID of the housing recess to aid fitment & if that seal has the spring on the back side, pack that recess with vaseline to help hold it in place. it is a good idea to grab a helper to hold it and the pipe (get a piece of pipe with a wall thickness wide enough to cover the seal width). critical is the first few blows to get it started straight. You likely need to sand the ID slightly to remove burrs and clean the paint off of the seal OD (every bit helps) as it sounds like there might be a few tho too much interference. As you know don't let the debris from any sanding/polishing end up where it ain't supposed to.

Thanks for the replies guys. I'm still wondering if there isn't a tool that's made specifically for this. I've seen some but cannot find one specifically for my application.

If you can find a piece of exhaust pipe or plastic pvc plumbing pipe or whatever you have laying around that fits the pinion seal you can use that to drive the new seal in evenly instead of the piece of wood. The second pics shows that this isn't the perfect fit to look for but hopefully you get the idea

Thanks for the pics. I know this should be a simple install. I guess I'm just being over cautious because of my first failed attempt.

And pack the seal garter spring with grease to keep it from popping off from the hammer blows.

As a teenager worked in a small town garage. My boss would run a dab of STP around the outer rim of the seal housing and the inner rim of the differential. He liked STP for many things where the fit was tight,,,piston pins, bearing races, cleaned bolt and nut threads, etc.

Appeared reasonable to me, have been known to do it yet today.

http://www.eastwood.com/10-pc-bearing-an...CFQpWDQodgQ8GNA

they may have given you the wrong seal & more likely I think some brands, the OD is a slight bit too large which it sounds like you may have run into. when you get the new seal just hold it up there & you will be able to tell if it can be easily driven in.