Buck268

Long story short, my firebird is about to die on me and in more ways than one is not worth spending money on. That said, I do need it to last as long as possible.

The situation: Eyeballed a front end alignment in the fall before putting my snows on. Figured at least the steering wheel was straight and the car didn't pull like it did before. After several months, 3 of my 4 tires look great, with just the pass. front showing excessive wear.

Both front tires show feathering along the inside of the treadblocks (across entire width of tire). Driverside has fairly even wear. Passenger side has virtually zero wear along inner half of tire and is almost bald on the outter half. The wear is even circumfrunctially (I know, spelling...) and fades to less to no wear as it crosses the mid-point of width.

Given an unknown alignment spec, steering wheel typically rather even during driving on flat roads what would the suggected adjustment be? Despite the indication towards positive camber, the eyeball method suggests a health amount to the negative and eyeball-straight toe. Steering linkage is all newer (and nice and tight). Balljoints and upper strut mounts have seen better days, but nothing rediculously excessive. Any ideas for the ghetto-rigger DIY alignment are welcome

Buck268

So far everything I've dug up indicated excessive toe-in to be the primary culprit for excessive outter-edge wear, which makes sense. But why would this only occur on one side? Perhaps something else is at fault here? Like I said, though, eyeballing appears to have a very slight negative camber which should lend to the idea that is not the issue.

Guest

Drivers weight on the left side will favor that tire tracking straight and the lighter right side of the car scrubbing. I would guess your ball joints are shot badly as well.

Another note on drivers side weight- anyone ever notice that the left side brake pads will always wear slightly faster on alot of cars? This too is very common on a car that generally sees only one person driving in it with no passengers.

Buck268

Well, I suppose I can see the logic there, especially since I virtually never have any passengers- but would a 215lb driver really make that much difference?

And FWIW, I measured my toe (used the pin-in-tire-at-constant-height method) and I had about 7/8" toe-in. Extended the passenger tie rod approx 5/8" and it behaves *much* nicer in turns and over bumps, need to even that 5/8" between the driver and pass tie rod though, still.

safemode

iTrader: (1)

I had outter edge wear issues when my bearings went south in the rotors (you'll have to check inners and outters). Best way to look at that is to see if there is play in the tire by pushing at the top of the tire and pulling at the bottom and seeing if it wiggles, and vice versa. It shouldn't wiggle. I had to replace not only the bearings but the races since the rotors came from an even older car (which i wasn't aware of initially).

Buck268

I replaced the bearings and races when I did the brakes as part of the repairs required to get her rolling again last winter. Actually they have given me nothing but trouble, I've had to go back and re-adjust them twice now. If it wasn't cottered, and swear the damn nut is backing off! Never had a problem like that before with all new parts. So in other words, I think thats a good idea and I'm going to have to check again...

safemode

iTrader: (1)

sometimes it feels like the rotor is on the spindle but it's not really all the way on. That's the only way that nut would seem like it is backing off on you. You have to really push to get the new grease seal seated on the spindle. Once you get he nut on and cottered, you should try tugging out and pushing in on the roter to see if you have any play.

Might also be a good idea to examine the bearings if you've had to re-adjust ....perhaps you're chewing them up for some reason (overtightening or insufficient grease or not using the correct grease ...etc).

Norm Peterson

What you need to do is set up parallel strings and set toe that way. Being off by, or when adjustments of 5/8" makes things better means that you've been way off. I suspect the passenger side may have positive camber.

I do have a couple of DIY alignment write-ups if you're interested. Best sent as an attached file to an e-mail.


Norm

sled_fiend

Just some general info about alignments and tire wear. As most of you know trying to solve an alignment problem on a car with old and worn parts is like nailing jello to the wall. You can align it perfectly on a rack but the second you put that car back on the road with worn out ball joints, tie rod ends, drag link or whatever...bamm...there goes your alignment. Once you verify that all the steering components are good and/or change the ones that are bad you can align the vehicle.

Feather wear across the tire is from scrubbing sideways (toe in/out) the sharp part of the tread block is the trailing edge the rounded part is the leading edge. If both tires have feather wear and the sharp sides are on the inside then you have excessive toe in. The toe may not be equal on both front tires also so you may only see feather wear on one and not the other.

Excessive wear on one side of the tire can be caused by excessive toe also, maybe exacerbated by camber problems. Like the other guys said, check bearings, ball joints, everything. Sounds like you have a lot of worn parts that are contributing to your wear problems.

A lot of alignment shops will put your car up on the rack for free and check for play in the bearings, ball joints, etc. for free. I'd recommend your local Firestone service center (since I'm an engineer with Bridgestone)

If anybody ever has any questions about tires (wear, performance, anything) PM me and I can find the answer for you if I don't know.