Low profile tires treadwear

[kowalski]

My C43 has Good Year Eagles GSD F1 V-TREAD tires
(X-TRA LOAD: XL TIRES)
I have noticed that the inner/outer tread is worn, the middle section is good normal wear!

I used to pump air about 32psi all around when cold, but I am not shure if this was to much or to little for my tires!
Now I pump only 28-29psi all around!

I can't save my front tires but the rear ones are still like new after 2 summer seasons, driving my car!

Front: 225/40/18
Rear: 255/35/18

Fronts are worn a lot on inner/outer tread, not middle section!
Rears are hardly worn at all, they are still like new!

I thought high powered rear wheel drive cars will wear out the rear tires first then the fronts, here is the opposite!

My car was aligned with 17 inch wheels, but the 17 inch tires were worn the the same way as my 18 inch front tires!

Do I need to make a new alignment with my 18 inch wheels?

[svt ricco]

most of the owners here moved over on mbworld/mymbonline. yiou might get your answer over there.

[1995c280]

18" tires = more air

i used to run 35psi cold in all 4 tires. if the inner/outer are wearing evenly but not the center, then you don't have enough air in your tires.

your alignment is most likely fine. if it wasn't you would have different wear patterns on the inner/outer/center like inner bald everything else ok (etc.....)

[Logic]

most lower cars like ours wear like that . i usually run about 42 psi in mine. i usually get that extra out of the tires. when i ran 35 psi the inner wore alot faster

[kowalski]

Originally posted by 1995c280
18" tires = more air

i used to run 35psi cold in all 4 tires. if the inner/outer are wearing evenly but not the center, then you don't have enough air in your tires.

your alignment is most likely fine. if it wasn't you would have different wear patterns on the inner/outer/center like inner bald everything else ok (etc.....)

hey buddy.
inner/outer wear is near bald!
the middle section is full normal tread wear!
I spoke with the swedish Good Year HQ. they told me not to use more than 26 psi cold because they are XL reinforced sidewall!
I think this is to little air pressure!
I tried with 26 psi but it felt like my car was flat on the ground!
I used to pump 32psi, maximum recomended on tire side is 34psi= 340 kpa, not more becuse of explosion risk!
But 32 psi felt like I was bouncing on the road!
I lost all the comfort from my Benz, It felt less stability on the road!
Inside cabin was rattling more!
But was a little easier on fuel consumption!

Now I pump 30psi all 4 tires, but the fronts are worn, they can not be saved!

I am not shure how much psi is the best for 18 inch tires!
Larger inch needs more psi if I understand correct!

My fronts are 225
My rears are 255
What is the best air pressure for this setup?
less than 30 psi or more?

[Logic]

strange on my tires it says max pressure is 51 hmmmm. i guess it depends on your tires too i guess.

[1995c280]

the only difference on a XL tire is the sidewall is made slightly stiffer to account for heavier loads.

i checked tirerack's site as well as good year's site. every single eagle F1 tire they sell says max inflation pressure should be either 50 or 51 psi.

whatever goodyear said to you sounds like a bunch of crap to me. i have ran XL tires plenty of times (currently on my 06' BMW with 19's and i run 42 psi cold with no problems.

you are correct, the bigger the rims with lower profile tires, the higher the pressure. just don't run excessivly crazy high pressure because it will blow out if you hit a pothole hard enough at the right angle.

i still say run 35 psi cold all around and you'll be fine.

[kowalski]

Originally posted by 1995c280
the only difference on a XL tire is the sidewall is made slightly stiffer to account for heavier loads.

i checked tirerack's site as well as good year's site. every single eagle F1 tire they sell says max inflation pressure should be either 50 or 51 psi.

whatever goodyear said to you sounds like a bunch of crap to me. i have ran XL tires plenty of times (currently on my 06' BMW with 19's and i run 42 psi cold with no problems.

you are correct, the bigger the rims with lower profile tires, the higher the pressure. just don't run excessivly crazy high pressure because it will blow out if you hit a pothole hard enough at the right angle.

i still say run 35 psi cold all around and you'll be fine.


hallo again my cool forum buddies!
here in sweden we use the term for weight: kg=kilogram
1kg=1000 grams
so I used to pump my tires when they were new, about 3,2 - 3,3kg all 4 of them!
That means 320kpa-330kpa? If this is correct?
So not to get confused here, the information submitted on tirewall says inflation is maximum 340kpa!
340kpa must be 3,4kg I think?
Can you correct me if I am wrong?

My buddy told me not to inflate more than 2,8kg because it would be to much and that's not good for the tires!

We use the MAHLE portable pumps with kg scale and psi scale!

So I have studied the inner gascap chart for airpressure and it only informs about 17 inch tires!
And on this chart the maximum load is 2.8kg for 17 inch rear tires!
Fronts are about 2,3 kg or something?
That's to little of air pressure!

So if this is correct then?
Running 3,0kg all 4 tires is then 300kpa on each wheel?
Am I correct here?

I didn't like the 3,2kg setup very much, my car rattled inside the cabin and the car felt a little unstable at 130 mph on good surface freeways!
I only ran 3,2kg because I thought my tires would last longer, when reading carmagazines, experianced tiretesters recommend to inflate about 30% extra load and the tires will last longer!
That's why I did it for my tires to last longer!

So my fronts are fucked!
These can not be saved, I drive em' to the end!
But the rear tires tread is correct and in better shape!
I thought it would be the opposite with muscle cars that runs on rear wheels!
Cheers