Some thoughts on your bearings when hub flipping.

[bugwhacker]

Our hubs have the same race 3920 in the inner and the outer position. We use a 3992 or 3994 bearing in the inner position and a 392 bearing in the outer. This is fine and dandy on the day they are manufactured and makes keeping spares on the shelf easy as you only need one hub loaded with the same race on both ends for all positions on the truck. When flipping our used hubs though this creates a bit of a problem.


The reason is this -

The bearings we use are 2 differant widths on the taper face.

The inner 3992 or 3994 are both 0.9375" on the cup face and the outer 392 is 0.7411" that is a differance of 0.1964" - a little short of a quarter inch.

So when we flip our hubs we will have a 3/4" bearing running on a 1" race in the outer position - this will most likley be okay.
Then we will have a 1" bearing running on a 1" race in the inner position that has had a 3/4" bearing ran on it wearing a 3/4" path in it for who knows how long - this is less than ideal.

For low speed crawling out in the woods this is most likely not going to fail for a long time. Running down the hiway though this could be a problem.

I myself because I plan to run alot of highway miles will at the very least replace my inner race for $8 when I flip my hubs. Of course replacing all the bearings and races with new matched units would be the perfect solution.

The following spec sheet clearly shows this with "Cup width "c"".

 

[welldigger]

Just flip the races. Keep the same race with the same bearing. New bearing = new race. They wear together. Don't mix and match new and old.

 

[bugwhacker]

Flipping the races sounds like a good idea but from personal experiance rebuilding electric motors for a living I can tell you that getting a race out then back in without damaging it is **** near if not impossible. We should replace the race and bearings as a unit but I doubt if many ever will because of cost.

 

[welldigger]

I have flipped the races on many deuce hubs. Beat them out from the back. There are cut outs in the hub just for this purpose. Clean them up and freeze them. Then drift them back in with a brass punch. Easy as can be.

 

[talskinyguy]

Getting these races out without damaging them is easy, the hubs are built for it. Just as the other 2 people said flip the races with the bearings. It is what every how-to post on the subject that I have ever read says to do, and what I will be doing in about a month.

 

[rmgill]

Hmm, I flipped my hubs several years ago and I have a good pair of 700 mile trips on me to Pa and back. This past summer when I mounted up the g177s I serviced all 6 stations and noticed nothing odd or amiss on the bearings or races.

 

[ATPTac]

I have flipped the races on many deuce hubs. Beat them out from the back. There are cut outs in the hub just for this purpose. Clean them up and freeze them. Then drift them back in with a brass punch. Easy as can be.

Bingo. As long as you use the proper tools you won't damage anything.

 

[welldigger]

Truthfully if your careful the proper tools would be anything softer than a hardened bearing race. These things aren't fragile. I use a long hardened chisel to beat them out and the race must be even harder. It doesn't leave a single mark on the backside of the race. I use a brass punch to reseat them just to be safe and because I have one. Id use a normal drift punch if thats all I had.

The absolute best race seating tool is another bearing race with a slot cut in it.

 

[brianp454]

weldigger has this right. The issue bugwhacker brigs up is not an issue. This was a part of the design concept from the beginning, e.g. the M34 and M35A3. Both bearings have the proper contact in either flipped position.

Just flip the races. Keep the same race with the same bearing. New bearing = new race. They wear together. Don't mix and match new and old.