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The big blue truck (dually) is up for its safety inspection. I know the rear adjusters are locked up solid, and my 'pedal' has been pretty low lately. Not wanting to take the chance of failing, I figured I'd look at the brakes. Well, I learned one thing about these trucks...

Aint nothing easy!

I thougth that I would just take off the wheels and pop the drums off. HA! The drums are unit parts of the hubs. But with the help of a friend who is familiare with larger trucks, we dove into it.

I removed the axle flange bolts and with a very light amount of prying, the axles slid out. Use a catch tray, as a bit of gear lube will come out with them. Once clear, you will see a big nut with a key in it and a round circle-clip holding the key in. A flat blade screwdriver made short work of removing the clip, and a magnetic pick-up fished out the keystock.

With the keystock out, the big honkin' nut is free to rotate. Unscrew the nut and remove it completely. Not the hub/drum unit is free to be removed. This sucker is HEAVY. Get some help or a floor jack or something. I about busted a nut pulling it out. The bearings come out with the hub.

With the drums off, I could see that I had plenty of brake shoe left, but the adjusters were totally frozen. A little squirt of some PB blaster, and a big pair of pliers later, and they broke loose. I coated them in anti-seize, and screwed them all the way in and back out to make sure the inside threads got some anti-seize on them.

Putting the hub/drum unit back on was not fun. Be careful not to knock the bearings. First off, though, degrease everything inside the drum with some brake cleaner and give it a once over visually. My drums and bearings all looked to be in pretty good shape.

Once the hub/drum is back on the axle tube snout, install the big-honkin' nut. I have absolutly no idea what the torque spec are for this, so I used my best, "front-end-spindle-bearing-nut-tightening-by-feel" method. Not loose, not really tight. Just tight enough to eleminate any play, and then a quarter turn more. There are a bunch of keyways in the nut that will line up with a keyway in the snout eventually. My 1/4 turn more actually wound up being slightly less on both sides, to get the snout keyway to line up nicely with a nut keyway. Then slide the keystock back in and re-install the circle-clip.


The axles then went back in with a bit of silicone to seal things up. I installed the wheels and tires, and then set the brake adjustment through the little hole in the backing plate.

A heavy, and dirty job, but not too difificult for the average mechanic.

Tim
 

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Mine is getting close to needing a brake job back there too. Too many burnouts I guess.

A general rule of thumb is if the bearings are grease packed you leave clearance and not a preload and if they are in an oil bath (as yours are in the 14 bolt) you preload the bearings. There likely is a torque spec for the bearing nut but you will be very close to it with your assembly method anyway.

Also another good tip is to hit the end of the axle with a big hammer once the retaining bolts are removed. The shock will often pop the axle out even though you hit it on the outside. It is not so critical on the 14 bolt to loosen the axle but many of the older trucks that had a Dana supplied rear end it was absolutely nessicary.
 

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Good post, other Tim\Cr -

As I knew my drums did not need surfacing, I bought a 60buck hydraulic ATV jack from harborfreight, jacked the diff up, slid the ATV jack under the dually tires\wheels\drum combo, eased up on the lift platform to take the load, strapped the assembly down, and backed it off the diff spindle.

Went back same way - no fuss, no muss, no 1500bucks for a snapon wheel dolly.

Oh, yeah - I'm bad, I'm bad, I am sooo bad.........:cool:
 

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I tink someone just a winner for the FAQ's...
 

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Dont forget to jack one side up to let the oil flow into the hub, then lower it and do the same to the other side....DONT assume that when you drive it the oil will make it to the bearings. I've seen them sieze a couple of days later on the old Canadian Army chev 5/4 ton (circa 1975) from lack of oil in the hub area.
I always grease the bearings when ever possible even if they are hypoid feed
 

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:nopics:
 

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Yeah - any pics?

I'm still not sure if my '99 3/4 ton Suburban has these same brakes. I think it does. I bought new rear shoes for it a year ago, and still haven't gotten around to putting them on yet. Partly because I'm still afraid of the job with the full floater.
 

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We need to chip in and buy Tim a cheapy digital camera he is not afraid to get greasy.

Two good posts in as many days with no pics!
 

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I found this post on another forum which confirms my hunch that my 'burban has slide-off drums:

http://truckworld.tenmagazines.com/forums/topic.ten?id=14346

Here is the relevant quote: "Two different 14-bolts exist. The 9.5" (semi-floating) is most common and comes on F44 equipped 1/2-tons and most 3/4-tons. The 10.5" (full-floating) comes on all 1-tons and some 3/4-tons (usually big-block or diesel).

I prefer the 88-99 bigblock or diesel 2500 Suburban rear ends since they are a 10.5" full floating design with slide-off drums. Yes, the drum comes off without removing the hub. BTW: its a 13x3.5" drum. "


I also saw a set of pictures a while back on the net that showed a 2500 Suburban with slide off drums on a full floater with 13x 3.5 drums, but I can't locate it now.

So has anyone here changed the rear shoes on their 2500 diesel Suburban with the 13x 3.5" drum on a full floater? Any tricks to getting the drums off? Even if the drums on my truck are supposed to slide off, can I still pull the axles by removing the bolts in the center of the axle flange in the event the drums are frozen on with rust?
 

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My 95 happens to have the full-float 10.5 with 13x3.5 shoes, with non-detechable drums. I did the rear brakes a couple of years ago, other than the weight of the hub/drum assembly, there were no problems. The bearings looked great, and the wheel cylinders were dry. I installed the new shoes and hardware, and new hub oil seals. Using a gauge to set the width of the shoes before installing the drum saved some time with the adjusters.
My 95 manual states to tighten the axle nut to xx ft/lbs while turning to seat the bearings, then loosen to a slight amount of play, like front wheel bearings, so that's how I did mine. That was around 50,000 miles ago, no problems since.

I've never touched a full-float w/ detachable drums, but by definition the axleshafts should be removable in the same manner as mine.

The biggest problem I could forsee would be a large rust lip on the inside of the drums, especially if the adjuster was frozen up too.
 

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Discussion Starter #12
minisub;1398323; said:
We need to chip in and buy Tim a cheapy digital camera he is not afraid to get greasy.

Two good posts in as many days with no pics!


yeah, I am a worthless SOB. You ought to take me out back and shoot me.

Actually, I got the camera out and had my bro-in-law standing by to snap some pics, but alas, the batteries were dead in the camera, and I didnt have time to charge them.

next time, I swear, I will get some pics.

Tim
 
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