New tires 8 months ago on my DD 89. Inside fronts are SHOT! Aligned 3 times...I guess no one here can get it right. I did replace the wheel bearings...then aligned again. T/b ball joints are good. The wheels are 8" wide. I need to replace but I'm on a tight budget since being out of work the last 4 months. I am running 225/40-18 on it now but there is a set on CL locally I could get I think for $60 with 70% tread left.....BUT they are 255/40-18....far far from ideal. Is this so wide it would be unsafe? Thoughts on just how wide to go and be safe on a 8" rim?

Note...the pic was taken with the passenger side jacked up high.

Thanks

 

255 on an 8" is fine.

As to the insides being shot, how much camber are you running??? And what are your toe settings?

 

Colin...I don't know the settings or even how to check them. I don't think the shops gave me a read out. Alignments are like rebuilding auto trans...I've always paid someone to do that....I feel fine doing everything else. That being said...I could of done a better job at aligning than what I've paid for lately. And YES...I told each shop the car CAN NOT BE JACKED UP ( unload suspension ) and was told they wouldn't....I'm at a loss right now.

 

255 is fine on an 8" wide wheel, but the 40 aspect ratio will give you a higher sidewall, than your current 225/40.

 

Yes Matt...side wall will be an extra 1/2" taller...not sure if it will scrub. This I hope will be a short term fix.

 

Dean,

The picture just showed up for me in your first post and something is seriously wrong!

That is absolutly destroyed!

If we could get you to get an anglefinder/inclinometer and a 2x4 (lowes? Home Depot) and put the 2x4 vertical on the wheel and then put the inclinometer against this. This will tell you how much camber there is. But judging from the picture you just posted it looks like it is sitting properly.

If you could also take a picture perpendiular to the wheels from alittle ways off this will help.

As well is it ONLY the front tires which are wearing like this? Does the car trammline heavily? Or is the turn in really quick?

Normally if you have alot of toe you will see some feathering on the tread which is left, but I dont see any of that. You said you replaced the wheel bearings, are you sure you tightened them properly and properly tightened the anti backoff system? I would be jacking up the car and inspecting the wheel bearings, upper and lower balljoints for wear!

 

Your toe is WAY off (toed out). I just finished a DIY front toe calculator that is very easy to use. I will be putting a DIY thread together in the next few days. It's very easy to do yourself with some basic materials. I wish it was ready now to post.

 

Hi Colin...Thats why I had the car jacked up...I was rechecking the wheel bearing adjustment and ball joints. All fells fine to me...Not too tight and not too loose. I will post more pics tomorrow. The car handles fine to me but is pulling slightly to the right.....but it is the only S4 I have ever driven. My son has an 80 OB.

 

Thanks Andrew...I look forward to your post.

 

unless I am completely off Andrew when the toe is done incorrectly by jacking up the car when the car settles there is too much - toe.

So if AO thinks you have + toe, the shop that did it REALLY screwed up.

 

I may be mistaken about the excessive toe out vs. in, but it would make sense to me that if your wheels are toed out you would have a tendancy to scrub the insides. If they were toed in, you would wear the outsides. I suppose camber can also play into this, but those pics are pretty nasty no matter the current setup.

 

Andrew, your diagram is mostly correct, but with toe in you will see a feathering of the pads.

or you will also see the pad wearing faster on one edge.

 

Colin, that's correct if the ride-height is at the factory spec. At normal height the tie-rods should be horizontal. When the car is jacked and sitting high, then the tie-rods slope downwards towards the wheel, and pull the steering-arm inwards-- toe-out. If you fix that with the car high, and then the car settles, then it toes in.

But if the ride-height is below factory-spec then it goes the other way, and as the car settles then the angle of the tie-rods pulls the steering-arms in and causes toe-out.

Which is exactly what those tires look like, don't ask me how I know!

Dean, you need to find Earl's DIY alignment threads. Toe-in is easy, you can almost eyeball it. (Sight down both sides of the car, all four wheels should look like they are pointed straight ahead).

But also check your steering rack. With the wheels on ramps get someone to steer left-right-left a few inches of steering-wheel travel, and get under there and check for movement. Is the rack housing moving side/side or fore/aft in its mounting bushings? Then check the inner and outer tie-rod ball joints (pull the rack boot back and let your fingers do the investigating), and then check for any radial movement of the driver's side rack-rod relative to the housing (i.e. side-play, at right angles to the normal motion of the rack). Because of the angle of the tie-rods any radial play will cause a toe-error. If the shop doesn't catch it (and in my experience they don't) then the alignment is AFU as soon as you drive out the door.

Andrew, Thanks for the picture! It is easily worth 1,000 words. And I look forward to your writeup, we've been doing our own alignment for a while and are much happier with the results!

Colin, I don't know why but I've never seen feathering on 928's. When we've had toe-problems our tires have all looked very much like Dean's picture.

 

Too much negative camber. IMO.

 

Jim, as to the feathering on a 928,

I have seen it on one of my own.