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Home » Public Forums » GMCnet » Newby Question - Repack Rear Wheel Bearing - '73 - 26" (How To : Repack Rear Wheel Bearing - '73 - 26")
Re: [GMCnet] Newby Question - Repack Rear Wheel Bearing - '73 - 26" [message #323828 is a reply to message #323820] Wed, 13 September 2017 08:43 Go to previous messageGo to previous message
77Royale   United States
Messages: 461
Registered: June 2014
Location: Mid Michigan
Karma:
Senior Member
The Rear Bearings can be removed with basic hand tools. If you dont know the condition of anything back there right now as far as service, other than it seems to work, you may want to strongly consider replacing some parts as to get to the bearings, you are giving yourself good access to inspect / replace other parts..

If you have the maintenance manual, that has a solid write up on how to go about it, and provides the torque specs for the rear castle nut. THAT IS CRITICAL to set the load on the bearings before you put the cotter pin in it. Its been documented in several threads on this board, and also in the manual, You really do need to follow that to the letter. and you need a torque wrench and socket that fits the rear castle nut. No way around that. The manuals can be downloaded on Bdubs site if you dont have the book.

To get at the inner bearings once the hub and drum are removed, you do need to remove the seal. Either with a seal puller tool, or some other method. Some have reused the seals if they are in good shape. I have not, and replaced them. The correct seal is an SKF 21771 and it needs to have proper clearance. Others have sourced different rear seals and they were not correct even though the parts crossed over.. You probably have a better chance of getting the proper seals by using the SKF brand. Napa has them.

So pull out the bearings and clean all the old grease off them as well as the races they ride in. Clean them good, but stay away from brake cleaner or any solvent to help in that cleaning job. It sometimes is impossible to get all the cleaner dried and out and you want grease in there. After a good cleaning, inspect the bearings and races for scoring, burn marks, pits, etc. These must be smooth. If you have any question or concern at all with the condition of either the bearing or race replace them both. I would not put a new bearing on an old race and vice versa. The are a matched set at this point, and that also means, DO NOT mix up bearings from the mid wheel with bearings from the rear. They all need to stay together.

Once you have the bearings and races clean and you are satisfied, you need to repack the bearings with grease. As your going to be doing 8 bearings I would buy a bearing packer tool for a few bucks if you dont have one. It will make your life easier and less messy. Folks here have used Valvoline SynPower or Mobil 1 synthetic or Caterpillar brand. No opinion on which is better or why. but I would use one of those. The synpower is grey in color, the Mobil 1 is bright red. The color in the Mobil at least helps you to confirm that new fresh grease is in there and the old black/brown grease is out. After all thats what your doing the job for anyway. Obviously you need a grease gun as well if you have a bearing packer and there are a million other zirk fittings that need fresh grease on the coach. Get a good grease gun, you will be using it.

Reassemble to the letter in the manual and your on your way.


BUT, While your in there. What is the condition of the rubber T brake hose on the back? If its original, it should be replaced. If its old, brittle, it should be replaced. Both sides. While your at it, same for the wheel cylinders are they super old, leaky etc. Replace those while your right there and you have good access to everything and everything is clean. While your at it. What do the brake shoes look like? You get the idea, replace them if they are worn as your right there to do it.

In a perfect world servicing the rear bearings is a few hour job, 30 bucks for 4 new seals, some good grease and peace of mind that you know they are good for a while. The reality is if you dont know the history of the service on stuff, you may wish to take the route of base lining those items with new parts and document it, so you have a much faster and less expensive service down the road.

Murphys law will bite, when you repack all the bearings, get everything set, a week later you find a leaky wheel cylinder, or something else wrong. Better to do it all in your shop/driveway, than on the side of the road. Dont get frustrated, early on in your ownership you may find that every 30 minute and 30 dollar job turns into several days and several hundred dollars, but there is a light at the end of the tunnel. You have already been enjoying to coach so that is a bonus.




77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson carb and dizzy. Mid Michigan

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