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Sun Jun 09, 2013 4:34 pm

So, I just replaced my drum about 500 miles ago and it stripped out again and i knew it would. my wheel starts to get all dirty with dust like when it's going bad. What I want to know is, what causes this? i used a torque wrench and got it to factory specs when i replaced it last time. 250 lbs. so i think something else is wrong. I have a 67 so it has the "z bar" swing arm and the bushings on the links were shot. so i replaced those could that have been it? also it's my passenger side that is going out. any help would be awesome.

Sun Jun 09, 2013 4:36 pm

Here's a picture of her.
http://i.imgur.com/x1jGbIH.jpg

Sun Jun 09, 2013 4:38 pm

Are you using German drums?

Sun Jun 09, 2013 4:42 pm

Check out this thread. Lots of information.
http://www.thesamba.com/vw/forum/viewtopic.php?t=263223&highlight=stripping+drums

Sun Jun 09, 2013 10:16 pm

Well mine is lowered 2 splines in the read i believe so that may be part of the problem. also I can only find Italian hubs. but what i will try this time is putting a shim or 2 behind the castle nut before i tighten it to make sure i get direct contact.

Mon Jun 10, 2013 8:52 am

Somebody wrote all over that poor girl. And why would you let her sit on your hood?

You have a lot of negative camber which isn't helping. Also if your rear toe is not close to where it needs to be that will also contribute to the problem.

At stock specs you can usually get away with Brazillion or Mexican drums, but running lower you really need to step up to good German drums.

Also take a CLOSE look at your axle splines! They need to be in good shape with sharp edges on the corners of the splines!

If they have worn, the new drum won’t fit tight and you get movement with every rotation of the wheel. That movement makes friction between the drum and axle which in turn wears out the splines in the drum.

This is the dirt and dust you begin to see on the wheel. Its actually fine metal particles off the drum.

Once things get worn to a certain degree, then splines just can’t hold anymore and they blow up.

The problem is you are introducing a lot of side load to the drum with the camber. The cheap drums just can’t handle that.

Not having the axle nut tight will also add to that.

Putting a shim under the nut may not be a good solution if everything else is assembled correctly.

Mon Jun 10, 2013 10:23 am

What do you mean if my toe is not where it is supposed to be? I cannot find German hubs anywhere though, only Italian. any sources?

Mon Jun 10, 2013 10:38 am

Edit: source = wolfsburg west

http://www.wolfsburgwest.com/cart/DetailsList.cfm?ID=111501615DGR

Tue Jun 11, 2013 8:10 am

Nathanthefreak wrote: What do you mean if my toe is not where it is supposed to be?

You have 2 parameters on the rear suspension you can adjust. Camber and toe.

Camber refers to the lean of the wheel. Right now you have NEGATIVE Camber – the tires are out at the bottom and in at the top . Positive camber would be the tires in at the bottom and out at the top.

Toe actually refers to where the front of the tire is trying to steer. If the tire is trying to steer away from the center of the car you have Toe OUT. If it is trying to steer towards the center of the car you have Toe IN.

Both toe and camber have an effect on the strain at the splines of the drum. Its obvious with a lot of negative camber that there is extra side loads being put on the drum. But if you have too much toe in or toe out, you are also introducing extra scrubbing which has the same effect of adding a lot more side load to the center splines of the drum.

Basically the rear tires are scrubbing the pavement in place of tracking straight ahead.

Toe can be set by moving the axle forward or back in the slotted holes in the ends of the spring plates.

Going as low as you are now, you probably have toe in unless you have extended the holes or installed extended spring plates.