14 bolt Full Floater brakes R&R info

[Cowracer]

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

[NH2112]

Replacing bearings on these things is fun. You probably noticed that the design of the hub prevents you from just taking the outer bearing out - you have to remove the wheel seal, take the inner bearing out, then knock the inner race out from the outside end of the hub. Next, remove the big snapring that the outer race seats against. Then you have to turn the outer bearing perpendicular to the hub and knock the outer race back through the hub. Then the outer bearing comes out from the inside. Assemble in reverse order.

PS - You'll want something like this (http://buy1.snapon.com/catalog/item.asp?P65=&tool=&item_ID=6955&group_ID=768&store=snapon-store&dir=catalog) to remove that snapring. Due to the depth at which it's seated and how thick it is, standard snapring pliers won't work.

BTW, the hubs and drums are separate pieces held together by the wheel studs, but corrosion often makes them look and act like they're unitary. A BFH is the best tool for separating them, simply put the hub on a small block of wood so the drum's not touching the ground and beat the holy hell out of the drum till it comes off. :)

[gmctd]

Good info, folks - this might help with the back-breaking part

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 - and no thread\keyway damage to the new seal.

Oh, yeah - I'm bad, I'm bad, I am sooo bad.........http://dieselplace.com/forum/images/smilies/cool.gif

[trbankii]

Just had mine apart a month or two ago - I agree that it isn't nearly what brake work on smaller vehicles is like!

A couple tidbits - AutoZone had the special socket to remove the funky spindle nut in their "free rental" tools. As it was less than $20 I just bought it outright so I wouldn't have to run to the store the next time, but you can return it and get your money back. The "magic" number is 50 lb/ft on torquing it back on.

There is a lot of good information here: http://www.pirate4x4.com/tech/billavista/14b_bible/index.html

Pirate4x4 can be a bit salty on the bulletin boards, but BillaVista is a good wealth of information.

[DmaxMaverick]

GM's updated tightening procedure is very important. The bulletin includes the 10.5" and 11.5" full floater rear ends. The bulletin # is 02-04-20-002, dated May, 2002.

Ensure the seal is completely seated on the spindle. Tighten the nut to 52 lb/ft, while rotating the hub counterclockwise a couple turns. Once you are certain the bearings and seal are properly seated, loosen the nut until it is loose. Retighten the nut to finger tight. There must be ZERO torque on the nut. Turn the nut counterclockwise (loosen), if necessary, until the keyway lines up. NO MORE THAN one slot to line it up! Secure the retainer.

[trbankii]

Thanks for the update!

I'm a bit surprised that there is that much of a discrepancy in instructions - 50 lb/ft to finger tight?

[JohnC]

Oh, yeah - I'm bad, I'm bad, I am sooo bad.........http://dieselplace.com/forum/images/smilies/cool.gif

Laziness, not necessity, is the true mother of invention! ;)

[murphyslaw]

Laziness, not necessity, is the true mother of invention! ;)


I use a forklift, HA

[MTTwister]

How many miles can ya normally get on a set of Rear Shoes before you have to dig into this?

[murphyslaw]

I have about 30K on mine right now, and there not showing any signs of givin up and this is a DD with 38's

[Shikaroka]

My 96 Suburban has the 14-bolt, 10.5", full-floating, rear end; but my drums slide right off after removing the wheels.
Is this something they changed at some point.

I have a leaking rear seal, so I plan on diving into this soon.

[NH2112]

How many miles can ya normally get on a set of Rear Shoes before you have to dig into this?


It's really not that big of a problem, IMO....but that might be due to the fact that everything I work on except my truck needs brakes done the same way LOL

Basically I'd say you're looking at an extra 15 minutes per side for removing & replacing the hub, wheel seal, and axleshaft. Add another 15 minutes each per side for R&R the drum and wheel bearings. The wheel bearing socket (OTC, Snap-on, Matco, etc) runs about $25, it's 3/4" drive so you'll need an adapter for your 1/2" drive stuff if you don't have 3/4" drive. The snapring pliers are more expensive - $85 from Snappy, don't know what KD, etc, get for them - but you definitely need them.

From what I understand, the 95s and later used slide-on drums like a 1/2-ton. I don't know if the hub design remained the same, with the snapring for the outer race and "out the back" disassembly/assembly method.