Jump to content
Ultimate Subaru Message Board

Rear Drivers tire wear inside


Recommended Posts

I have a 89 gl with 285000 miles. The inside of the rear drivers tire is wears down fast. All other tires have even wear. Don't suspect the bearing no wobble when I jacked it up. The wear isn't totally consistant on the inside there is a spot that is a 12in band that is worn deeper than the rest. But the whole inside is worn considerably more than the outside.

 

I'm thinking it could be the rear strut is bad. From what I understand there isn't any adjustment to the rear alignment.

 

I do carry a fair amount of weight in my trunk at all times. Mainly a couple hundred pounds of tools.

 

Any ideas?

 

Thanks

Link to comment
Share on other sites

i had a similar problem with one of my rear tires wearing considerably on the inside, i took it to the alignment shop, they said they could do nothing, it was close to specifications. i had thought, bad bearing, but it was fine, might want to check your suspension, loose trailing arm maybe, all the bushings etc.. mine are slightly worn, i got new tires and decided to live with it, hope this helps.

Link to comment
Share on other sites

You need to post up specs where the vehicle is on an alignment rack. Sounds like you have either negative toe, negative camber or both. Unless there's worn out parts or bent parts, its all adjustable in the back end. Just have to find an alignment tech willing to take the time on it.

 

Only thing that could be bent to cause that wear like that would be a bent trailing arm.

Edited by Caboobaroo
Link to comment
Share on other sites

Thanks guys.

 

Took another look at it today and noticed the drivers side bump stop is hitting it's plate on drivers side rear and there is a good 1in to 1 1/2in clearance on passagener side rear. Thinking this might be more evidence that the rear struts might need replacement.

 

Any thoughts?

 

Thanks

Link to comment
Share on other sites

You probably just need to do a rear alignment. It's pretty easy to do with a tape measure, I've done it a few times on my 89.

Here's the page from the FSM describing the rather esoteric process.

 

scan0001-1.jpg

 

If that doesn't make sense, drink a beer or two, maybe it'll help...

Link to comment
Share on other sites

Had alignment checked today. Here are the results:

 

LF

1.1 deg-Camber

1.7 deg-Caster

.00 deg- Toe

 

RF

0.6 deg-Camber

1.9 deg-Caster

-.04 deg- Toe

 

LR

-1.6 deg-Camber

-.09 deg- Toe

 

RR

-1.6 deg-Camber

-.40 deg- Toe

 

And the owner of the place said there is no adjustment for the rear and I would just have to keep replace the tires. Anyone know a place in colorado that might be willing to mess with it?

 

Thanks.

Link to comment
Share on other sites

All that toe on the RR seems odd. But if you're sitting on your bumpstops, some springs and shocks might be a good place to start.

 

As far as alignment goes, just try sighting down the length of the car. If it looks okay it's usually pretty close. You would probably notice immediately if the camber were too much, so you're probably gonna look for too much toe in or out.

 

And if it is too far bent to be adjusted, here's a trick for those on a budget: get another car and a tow rope, and yank on the thing a bit! If you have a welder, though, that would probably be preferred. :D

Link to comment
Share on other sites

yeah that was my thinking too. I asked they guy at the alignment shop and he said shocks/struts only keep you on the road. But I think that a worn out shock would effect the geometry of the rear end and thus make weird *************** happen.

 

Thanks for the imput

Link to comment
Share on other sites

Now that I have specs I can help out a bit more.

 

For those of you that don't do alignments for a living, this will help out. I've done several of these cars from wagons, sedans, coupes and even a couple XT6s.

 

There are adjustments but most alignment guys either don't know about the adjustments or realize how much of a pain they can be to get right. You can use a tape measure but if its tire wear you're concerned about, that's not my suggestion. The reason why they are such a bear to align is because the alignments head has to be attached to the wheel but the wheel has to be removed in order to get everything loose and to shift it around. I find it's easier on cars with 5 lug conversions and that are running a 17" wheel.

 

Now, the actual adjustments are just a loosen up and shift around but camber and toe are both effected by them. From the looks of it, you probably have a bad spring so fix the broken parts and find someone to do a proper alignment. Toe and camber can both be fixed in your scenario if everything checks out and nothing is bent/broken.

Link to comment
Share on other sites

A good way to check toe yourself is to get two thumbtacks, put them in the tread of left and right tires so they are parallel to the ground. Measure the distance between them. Then roll the car back or forward so the tire rolls 180 degrees (don't roll over the tacks, roll so the tack goes over the top), then measure distance again. Then do some maths with the radius of the tire to get the angle at which they compare.

 

And alignments don't have to be super accurate. Once you hit a speed bump, everythings off a bit.

Link to comment
Share on other sites

Please sign in to comment

You will be able to leave a comment after signing in



Sign In Now
 Share

×
×
  • Create New...