What the Hell?!!

I was inspecting my car yesterday and noticed that the inner sides of both of my back tires are worn down to the metal strips. My car only has 7,000 miles on it! The front tires and the outer part of the back tires look normal.

I know that the back wheels on these cars tilt in a bit, but that kind of wear is ridiculus. Is there anything I can do to prevent it from happening again? Where can I learn how to adjust the ride height?

Thanks!

I enjoyed the same bum trip last summer at about 3k miles. Went to see the ol' German wrench who told me the wear was normal because of the negative camber of my swing axle. He simply told me to rotate 'em. Nothing like that 50 year old technology is there?

Brian -

My Speedy (Vintage with swing-axle) hasn't experienced the abnormal tire wear you describe.

I looked at your car in your photo file and it doesn't appear to have any noticeable negative camber, unless you've lowered it since that picture. It may be probable that the rear torsion bars are fatigued and cannot maintain the proper camber when a driver/passenger are on-board.

I'm sure that people much more knowledgeable than I will soon offer some trouble-shooting solutions for you!

Could it be due to excessive toe-out rather than camber?

I'm with Lane. You are probably scrubbing the shoulder off. The negative camber shouldn't have that extreme wear pattern.

I am thinking Diet?

Actually I'm experiencing the same with my car and I'm pretty sure it's normal for lowered swingaxle cars. If you raise the rear a little the tires will wear more evenly. In my case, when the tires wear on one half I'll just flip the tires in their rims because there's no substitute for that mean lowered look! (as in originals).

If your car came with adjustable spring plates it's just a matter of turning the Allen bolt on each spring plate equally on both sides to raise "to taste". In my case my car came from VS with one adjustable spring plate on one side and a conventional one on the other side. I just bought a pair from Serrano's (see his classified ads in The Samba.com) for $85.00 and wouldn't you know it, when they arrived they matched the adjustable one in the car so I just replaced the non-adjustable one and kept a new spare (!!!).

Brian,

Bruce and Lane have the most common culprit for excessive inner tire wear. Camber can also be the cause, but it does sound too excessive to be camber alone... maybe a combination of toe and camber.

Is your transaxle swingaxle or IRS? Do you know if the springplates are slotted for adjustment forward and backward? Are they adjustable for ride height?

Adjustable springplate pictured below.

Be happy to walk you through checking toe and adjusting if needed.

Well, I'm 5'11 and 185, so I don't think my diet is the problem...though my wife would disagree. I think it's significant toe-out, and after looking at the angle of the tire...it's WAY out. So perhaps raising the ride height will help. Could one of you guys post a picture of the allen bolt that I should look for on the spring plate? I'll also check my books.

Thanks!

My car is set with the inside top 1/8 closer than the bottom inside -- measured with a tape measure from one side of the car to the other. When I sit in it, it only makes a 1/16" difference toward vertical.
I'd describe that as ideal for my car, but dif'rent strokes ...

Ditto on inside rear tire wear due to toe-in/out versus camber. My experience came from a '62 Corvair swing axle, back in the day. Shade tree (literally) mechanic swapped 3 speed for 4 speed. He forgot to re-install the engine shims that controlled toe-in. Drove less than 1000 miles and thoroughly trashed two new rear tires. You could actually look down, on the side of the car, and see the tire toe-in. I bet it was about one inch! New shims and a rear alignment solved everything. Lesson learned.

Brian, The ride height won't help. Bring the wheel back around.

Thanks guys. I appreciate it.