Rear drum scraping on backing plate

[brooklynvan]

Hey Vanafriends.
Been awhile since I've posted here. life is busy, kids and all.

I'm having an issue that started about a year ago. passenger rear of my 1990 tintop (Bostig powered FWIW) there was a bearing/cv humming noise that was intermittent along with a pulse in the brake pedal that I couldn't find for the life of me so I drove with it.

It was also making a scraping/squeek at low speed (my kids said it sounded like a dog panting) but this sound was unrelated to brake on or off. seemed to lessen when accelerating v. coasting/stopping

The scraping happens only after some driving (like 150mi plus) so must be heat related I think.

Early spring this year I replaced the OG axles with CVs et al. didn't help (but one OG CV was bad)

still had the pulse but all else was well, stopped fine etc.

In getting ready for ~5000miles in early August I decided to figure this out. discovered that the cylinder was bad on that side, so had new cylinders, shoes, etc put on. braking was great. still a pulse in the brake pedal.

I found a topic in the bay forum about the spacer in the rear wheel housing wearing causing this issue, or the castle nut being loose. took a look and mine was loose. so I tightened it.

Pulse was gone, and so was the noise!

got to KY on August 20 to view the eclipse and the noise and pulse returned. visited a great shop there called the Import Doktor and they found the nut loose again. they tightened it again and sent me on my way. by the time I hit Pittsburgh the noise was back.

It's not a bearing noise, it's rotational to the wheels and is for sure the drum rubbing the backing plate.

I found a posting on the Baywindow forum about this issue (same rear design as the vanagon) and it was suggested that it was the spacer wearing.
So I ordered new spacers and new rear bearings for both sides.

Had them done about two weeks ago and all was well. no more pulse in the pedal, no noise, great!

drove the RI and NH over the weekend and on the way back to NY (in hellish traffic last night) it started making the noise again.

I'm at work and haven't had time to take the wheel off to check the nut, but WTH!!!

If it's loose here's what I think might be wrong, but I'd love some thoughts or experiences from the community:

1. nut wasn't tightened to spec. so it needs to be snugged to 360ft lbs.

2. axle shaft is bent?

3. hub is bent?

thanks for your help!
_________________
1990 Vanagon "Plain Jane" Bostig in the Back
TRADED: 1967 Panel for 1976 BMW 2002
SOLD: 1984 Sunroof Vanagon with EJ22
RIP 1986 Saab turbo
and my daily commuter: a Bicycle

[Christopher Schimke]

Check the fit between the splines of the stub axle and the hub. If there is a lot of wear, there can be movement between the two which can lead to the nut loosening up over time.
_________________
"Sometimes you have to build a box to think outside of." - Bruce (not Springsteen)

*Custom wheel hardware for Audi/VW, Porsche and Mercedes wheels - Urethane Suspension Bushings*
T3Technique.com or contact me at [email protected]

[brooklynvan]

Thanks Chris,

when there is wear at that intersection of parts, in your experience is it the hub that wears? or the axle shaft?
_________________
1990 Vanagon "Plain Jane" Bostig in the Back
TRADED: 1967 Panel for 1976 BMW 2002
SOLD: 1984 Sunroof Vanagon with EJ22
RIP 1986 Saab turbo
and my daily commuter: a Bicycle

[Christopher Schimke]

I have seen both with wear, but I have seen more stub axles with damage than the hubs. That doesn't mean that the stub axles are necessarily more susceptible to damage, it's just what I have seen. Other's may see more damage to hubs.
_________________
"Sometimes you have to build a box to think outside of." - Bruce (not Springsteen)

*Custom wheel hardware for Audi/VW, Porsche and Mercedes wheels - Urethane Suspension Bushings*
T3Technique.com or contact me at [email protected]

[foamermetal]

So what ever happened?