Not_So_Fast_Eddie

So in may I had my new rims mounted/balanced along with a full alignment done. Now in December I've already lost a fair amount of tread within the 8,000 miles I've driven. What's odd though is all 4 tires literally have the same wear of 8/32 on the inside and 6/32 on the outside. These tires started at 10/32 so to lose half of the legal life span on the outer edge within 8,000 seems absurd.

The only tire out of spec is my RR with the camber being -1.7%. I'm running at stock height and the only difference in these tires from previous is an increase in tire width from the OEM size 215/60/16 to 235/45/17. Could it be suspension related? On my last tire set I never had a outer wear issue.

(Tires are Goodyear Eagle GT v rated)

justnspace

iTrader: (1)

camber doesnt cause wear, toe does.

is Toe set to 0?

Not_So_Fast_Eddie

Here's the tire spec set for toe:
Front Left: 0.0 degrees
Front Right: 0.0 degrees
Rear Left: 0.1 degrees
Rear Right: 0.1 degrees

Could it be the rears? It was done at tire warehouse and the sheet claims 0-.3 degrees is acceptable.

justnspace

iTrader: (1)

your toe looks great!
they're all set to 0, or close to it.

however, that doesnt mean the alignment could have gotten screwed up since May, tho.

d1sturb3d119

iTrader: (1)

Do you corner aggressively?

Also sounds like the increase may be messing things up. What tire pressure are you running. I had wider tires on my rims which caused the outer edges to wear quicker. Sounds like they may be a little under inflated for their size which is why you're having that issue.

What is the width of your rims. Are they like the stock wheels or a different size.

I was running 235's on 7.5 inch wide rims. Half an inch smaller than stock and the 235's were a little wide for it so I had to up the inflation. Now I run 225's which fit great and put down a better patch so my traction has increased considerably.

Tire info
http://www.carbibles.com/tyre_bible_pg3.html

Not_So_Fast_Eddie

What do you think my best course of action is? I really don't want to let it go and see the tires junk in another 8,000 miles.

justnspace

iTrader: (1)

vidur brings up a great point that I missed!

how is your tire pressure!?!??!

Not_So_Fast_Eddie

Sorry Vidur I missed your post. I'm running the 07 TL rims that are 17 x 8. Stock size was 16 x 7 (I think). I didn't check my Tire pressure until November where it was at 34 psi. I upped that to 36 psi as I had been experiencing some tire thumping when they were first cold.

Most of my mileage is highway as I take 2 different ones to get to college each morning and evening but I only drive every other week (commuting with friend). I'll admit it one of my favorite things is to enter corners harder than I should, I don't do it 24/7 and I don't do it to the point of the tires feeling like they will give out. More like past the point where my spare change starts to slide around.

d1sturb3d119

iTrader: (1)

For now with the tires you have, try inflating it some more. Start with 3psi and take regular readings to get a bearing of how its affecting your tires. Also factoring in temperature since its winter, up your tire pressure by 1psi for every 10 degree drop from ambient temp in the summer. I use 70 degrees as a reference point and then up it from there. Given the low temps, air ends up being denser and since you're upping your tire pressure while the temp is low it will not expand as expected during the summer.

As far as the rim size goes that should be 8 inches should be perfect for a 235 wide tire. At 35 psi you're looking at stock pressure for a TL. The best you can do is up the pressure.

With no camber adjustments and hard cornering you're going to see the car plow and wear out the edges quicker. The key is to feel what the gripping point is and keep the car within those limits so you're not causing pointless understeer. You'll know when its happening when you turn the wheel and the car takes a second to react and change direction then gives you too much of a direction change. It should always be a smooth transition. If you hear squeal you're scrubbing speed and rubber.


I'm planning on dialing in 1 degree of camber to offset the scrubbing and to give better traction through the corner.

Learned that one in autocross. Try out an event sometime. Give you a lot of confidence know what the limits of your car's grip is and what the limits of adhesion are. Haven't lost control or induced understeer ever since.

For future reference depending on what you feel you may want to decrease to a 225 so that the contact patch is well rounded on the edges and you aren't scrubbing rubber. That is more of a preference though. You may want to figure that piece out. Takes a lot of trial and error.

Not_So_Fast_Eddie

That's a lot of helpful info haha. What's the max PSI I could run in the summer? This car was suppose to be parked now for winter but I have a bearing noise I'm having checked tomorrow. I'll (try to) slow down on my turns to save the tires.

Which direction of camber is desired for hard turning positive or negative? Is that something lowering the car would help with?

d1sturb3d119

iTrader: (1)

All I can suggest on max PSI is not going beyond what's recommended on the tire. I believe mine's at 50PSI. I wouldn't even try going close to max.

Negative camber is what will help with hard cornering. Lowering the car would produce camber naturally. Not sure what it would come to on its own but a camber kit would help you adjust it accurately. Lower it then do an alignment to check. I'd say at 2 degrees you might see some uneven wear after many thousand miles. For the most part you want to keep it sensible since too much camber would reduce your contact patch and reduce traction while accelerating from a stand still. Also more camber makes low speed steering heavier.

Mr Marco

You have the tire inflated to 50PSI? Or the max PSI on your tire is 50?

d1sturb3d119

iTrader: (1)

The max the manufacturer recommends for my tire.

Not_So_Fast_Eddie

Vidur I really appreciate all the help, and I was hoping you could answer one last question. I've found I can buy an adjustable camber kit by Moog for roughly 200. The front can adjust to -3/4 degrees and the rear can go to -2 degrees.

What would be a sensible adjustment? Somewhere around -.5 degrees maybe?

d1sturb3d119

iTrader: (1)

I'm not sure about the brand itself. You'll have to read reviews on it. Yeah half a degree would be a modest amount. Like I said you won't feel any difference until you hit 2 degrees. Sounds like they have a lot of adjustability.

If you are planning on lowering the car do that first. Then invest in a camber kit.

It might be a little trial and error initially. Right now I have about 0.9 degrees of negative camber on the front left wheel and you can't visually notice a difference but the tread wear is very telling. You can start with half and if it eliminates the issue you're good or you may need to go to 1 degree.

OLD_HATCH

Be weary of inflating your tires to max psi listed on the tire.


Tire psi can vary about 5psi from cold to hot and you can exceed its maximum pressure rating.