End Play At Rear Wheels

[8thTon]

I have just noticed that there seems to be quite a bit of play at both rear wheels. If I jack it up and remove the parking brake I can move the rear wheel in ad out quite a bit. I have not tried to measure it but it seems excessive - you can hear them thunk back and forth. I have never messed with rear bearings or rear axles before, so I have no experience here. Do I read it correctly that the Maximum axle shaft end play is 0.030"?

Looking at the diagram it does not appear that the outer bearing is set up to take end thrust, so this must be on the inner end? How is it adjusted?

 

[55trucker]

There is no adjustment on either 7 1/2" or 8.8 rear ends. The thrust is taken by the ends of the axle shafts & the single lock pin between them that prevents the axles from moving inward & dropping out the U-clip retainers that are fitted into a groove on the ends of the shafts. This is inside the differential case.

 

[8thTon]

Well ok then. Looking at the movement of the inner edge of the drum in relation to the backing plate, I’d guess it’s on the order of 0.030”, so I’m going to forget about it for now.

I only noticed because the rear drums squeaked with the parking brake on when I pushed on the bed from the side.

 

[55trucker]

do you have a glazing situation on either side shoes?

 

[8thTon]

do you have a glazing situation on either side shoes?

I have not pulled them since I put the shoes on a month or so ago - they were so old and such a rusty mess I can't make much of a judgment from what was there. The drums themselves looked ok. Everything is working just fine and I have had no reason to even think about the rear bearings, etc, other than I happened to be pushing on things trying to find some minor squeak.

 

[55trucker]

If you live in a salt belt area the edge of the drum will form a *raised* area of rust. It's not that the drum contact area has worn but the rust has caused a ledge to form there. That too can cause a squeak, it will also cause problems trying to get the drums off. I get that here where I live, every so often I have to pull the drums and remove that ridge.

 

[Uncle Gump]

The squeak you hear is probably from one of two places. The park brake lever anchor pivot or the brake shoes moving on the backing plate. If it doesn't squeak with the brake pedal... I would look at the pivot.

I noticed yesterday my rear brakes have that notorious squeak every time I hit the brake pedal. I did rear brakes last year about this time... seems every spring I pop the drums off... give them a good cleaning and ensure the adjuster rotates and hit the backing plate contact points with a little lube. Then It's good until next spring.

 

[Bird76Mojo]

I had nearly 1/4" (or possibly more) of endplay in my 8.8" axle with the TracLok. When I rebuilt the TracLok I inserted additional steels to remove all of the endplay that I could. It also served to make the TracLok much more effective.

 

[8thTon]

With the parking brake on the shoes are clamped to the drums. If you pull the axle outward it pulls the shoes against the retaining springs, just a little. That is exactly the sound I heard, which is no big deal - I just couldn’t figure what it was. Then I felt the play and was worried.

 

[4x4junkie]

Axle shaft end play on these rearends generally is caused by the Traction-Lok (limited slip) clutches wearing (as the clutches wear thinner, the side gear (with the axle C-clip in it) moves away from the differential cross pin, which opens up a small gap between the end of the shaft and the cross pin). If it's only .03" of end play, you're fine. I've seen well over 1/8" of play without it causing any other ill effects aside from a mild clunking sound while driving slowly over certain types of terrain (driving over speed bumps at an angle for example).

 

[8thTon]

In this case it's an open diff, but it's good to know that level of play isn't a big deal.

 

[4x4junkie]

In this case it's an open diff, but it's good to know that level of play isn't a big deal.

Probably just needs slightly thicker C-clips then (there are kits available that have an assortment of different thickness clips). But yeah, it's a non-issue.

 

[Shran]

One of my 88s has at least 1/4 or more slop in the driver's side shaft. It's ridiculous. The other truck has quite a bit too. Where can I buy thicker c clips or shims? One does have a trac loc but the other has an open diff.

 

[4x4junkie]

You'll probably need to rebuild that Traction-Lok if it has that much play.

I know for a fact I've seen kits of assorted thickness c-clips somewhere, though just now I searched both Amazon and Ebay and came up dry, so I don't know what happened to them

Maybe a local rearend shop might have something?

 

[Shran]

Possibly, I will talk to Inland and see. I googled for a while last night and didn't find anything either. Just curious though, do the thicker ones have a recessed area where they slip onto the shaft? Seems like the normal C clips fit pretty well into their groove on the shaft and a thicker one would not fit into it.

I haven't taken either of these apart yet but I'm assuming, on the open diff 7.5, that the C clip is either worn very thin or has worn away part of the side gears?

Fully intend on rebuilding the other one. I'm sure it's way overdue. Or maybe I will 8.8 swap it with an axle that's in better condition.