Rear Brakes - Loud rubbing/scraping noise??

[92GMCK2500]

I would think drums. Normally you should be able to spin it and the resistance is the same. If you spin it and it drags a little then frees up then drags. That makes it should like something not perfect circle.

Makes sense. Has anyone had warped drums out of the box? They spun unevenly the first time I put them on, zero km's driven.

Solutions? 1. Have a machine shop check their true-ness, 2. If not true, have them turned. 3. Or, buy new drums again (i hate this option).

 

[92GMCK2500]

This is a crap shoot but maybe someone can shed some light on whether or not this can be related to my issues. The right rear axle shaft has in and out play/movement. Its not much, maybe like 2-3mm. In theory, this could suggest the drum to backing plate relationship is not snug, hence noises?

I just completed new bearings, seals and C-clips. The play before this was much worse, both lateral, up/down and side to side.

 

[SUBURBAN5]

If I were you I would have the drums checked and they could resurface them.
As far as play. I was under the assumption that there should not be play in the axles. What the history of this rig? Accident, tow a lot, orginal?

 

[thinger2]

Thanks for this ^ tip. Its worth inspecting and I might as well file out the shoe steel frame/plate to eliminate the potential burr problem.

If I'm understanding you right, you're saying you weld on new material onto the backing plate to gain the 'fat' back and grind it smooth again as its meant to be originally/new condition?

I've listed my suspicions in my OP. All calculated guesses at this stage. Interesting to hear others experiences. Cheers.

Yep. You weld the gouges in the backing plate then grind them back to smooth.
The trick here is to take your time so you dont get them so hot that they warp.
The plates are pretty thick but I still spent a day doing them just to keep them flat.
I mention this because a friend of mine went nuts on his with a harbor freight flux welder and warped the crap out of them.

 

[92GMCK2500]

If I were you I would have the drums checked and they could resurface them.
As far as play. I was under the assumption that there should not be play in the axles. What the history of this rig? Accident, tow a lot, orginal?

Thanks. Rig has been in the family since new. Towed fairly often in the past, fifth wheel, and been lugging a 9.5' camper around for 5 years. Full time rig, not daily though, drive 5-10k a year. No accidents, ever. Everything is/was OG.

 

[92GMCK2500]

Yep. You weld the gouges in the backing plate then grind them back to smooth.
The trick here is to take your time so you dont get them so hot that they warp.
The plates are pretty thick but I still spent a day doing them just to keep them flat.
I mention this because a friend of mine went nuts on his with a harbor freight flux welder and warped the crap out of them.

Cheers. I've never picked up a welding machine in my life. Never too late to start! Honestly, I'd be inclined to hit the junk yard first though!

 

[Chevy-SS]

Hmmmm, with all new parts, the slight drag as you rotate a wheel should be fairly consistent.

Have you narrowed down the trouble to the right rear wheel??????

You mention new bearings, which means you pulled the axles out. Did you happen to check them for straightness while you had them out?? Did you put everything back together correctly? 3mm of in/out play seems like a fair bit, but maybe within specs.

If you have grinding noise, you should be able to see where metal parts are rubbing.

 

[92GMCK2500]

Hmmmm, with all new parts, the slight drag as you rotate a wheel should be fairly consistent.

Have you narrowed down the trouble to the right rear wheel??????

You mention new bearings, which means you pulled the axles out. Did you happen to check them for straightness while you had them out?? Did you put everything back together correctly? 3mm of in/out play seems like a fair bit, but maybe within specs.

If you have grinding noise, you should be able to see where metal parts are rubbing.

The right rear axle is where I have in/out play and this is where it seems the rotation of the drum is inconsistent. I don't know the spec/tolerance so I am not sure if it is even an issue or not. The new axle C-clips that hold them in place reduced the amount of in/out play.

I did not check axle shafts for straightness with a straight edge, visually they appeared ok. I followed my haynes manual closely, cross referenced against A1 Auto and Eric the Car Guy tech. videos, and took my time.

Haven't got time during the week but I hope to start rechecking my work during the weekend. I'll keep you folks posted. Cheers.

 

[thinger2]

Cheers. I've never picked up a welding machine in my life. Never too late to start! Honestly, I'd be inclined to hit the junk yard first though!

Welding is very much like learning to play a musical instrument.
Practice,pratice,practice.
I always equate it with learning to play the guitar ( The worlds most frustrating and diabolical instrument)
The quality of the guitar you learn on can make or break your success.
The same applies to welding.
Start with a cheap Chinese welding machine and you will be frustrated and miserable.
Start with a decent actual mig, even an older used model and you will find it to be a usefull and enjoyable skill.
Good Luck!

 

[Erik the Awful]

+1, especially on buying a quality welder. Also buy a good helmet so you can see what you're welding. The basic $60 auto-darkening helmets are crap. You can buy a nice Jackson for under $150 and it's excellent.

When it comes to playing with cars, being able to weld really ups your game. My welding still isn't where I want it to be, but I can weld my own exhausts. I made my own transmission crossmember. I make tools on-the-fly. I can patch sheetmetal. I'm so glad I made the jump.