High center wear on rear tires

[JSolo]

^^Accounting for more cargo weight in the back¿?

 

[Ozstung]

That's cool. I just prefer to use an known accurate gauge. When I took my car out on the track some time ago the temps got pretty high and the TPMS wasn't reading correctly so I've gone back to trusting the gauge as a default.

With that said, I'm not running on the OEM wheels and rubber.

But definitely try running the rears lower ( even 32psi ) and see how it wears. Can't hurt.

I believe if the TPS detects a PSI reading of less than 34 psi then the warning comes up for that tyre.

 

[7Andrei7]

@JSolo I'm sure the readings are correct because I have 2 sets of wheels, each with their own TPS. Also, I always use different machines to adjust pressure and they always match what the TPS says. And, I set pressures on cold tires. In summer, at highway speeds, the TPS reads 2.7 or 2.8 bar for a tire that was 2.5 when cold. This is normal.

I'm fine with the milage I get but it just feels strange that the rears, which are the first to go, wear so much more on the center. I replace tires when they get to 3mm depth. So for example, when the rear center gets to 3mm, the outsides would have about 4 to 4.5mm left. Since tires start out with a 7.5mm thread seems that the center wears out up to 50% faster.

But, seems I'm not alone in this. So maybe it's just how the suspension is set up. I'm getting a new set of winters in one month so I'll try to keep the rears at 2.4 bar and the fronts at 2.5 bar. Will report back in a couple of years

 

[AusStinger]

I believe if the TPS detects a PSI reading of less than 34 psi then the warning comes up for that tyre.

Fair call. Couldnt remember the number.

I do remember dropping my pressures before going out on the track and I got the low pressure warning and even after a session when the pressures reached ~42psi, the low pressure warning stayed on. It actually didn't clear until the next day even with the pressures corrected. That was another reason I trust my gauge over the TPMS but hey, to each their own.

 

[AusStinger]

@JSolo I'm sure the readings are correct because I have 2 sets of wheels, each with their own TPS. Also, I always use different machines to adjust pressure and they always match what the TPS says. And, I set pressures on cold tires. In summer, at highway speeds, the TPS reads 2.7 or 2.8 bar for a tire that was 2.5 when cold. This is normal.

I'm fine with the milage I get but it just feels strange that the rears, which are the first to go, wear so much more on the center. I replace tires when they get to 3mm depth. So for example, when the rear center gets to 3mm, the outsides would have about 4 to 4.5mm left. Since tires start out with a 7.5mm thread seems that the center wears out up to 50% faster.

But, seems I'm not alone in this. So maybe it's just how the suspension is set up. I'm getting a new set of winters in one month so I'll try to keep the rears at 2.4 bar and the fronts at 2.5 bar. Will report back in a couple of years

I wonder if it has to do with your constant >70MPH highway milage over suburban/twisty driving....?

Maybe you need something more of an extra load tire?

Or maybe you should ease up on the burnouts.....

 

[7Andrei7]

@AusStinger Sadly, no chance to do a burnout with the 255 tires and my 245hp 2.0 engine
But, I was also thinking about the constant cruising. Maybe it keeps a steady higher pressure in the rear tires than what you would get in normal driving.

 

[nhcowboy28]

I always use the tire pressure on the sidewall of the tire……

 

[MerlintheMad]

I believe if the TPS detects a PSI reading of less than 34 psi then the warning comes up for that tyre.

I recently had 32 psi as my starting pressure and no warning.

Fair call. Couldnt remember the number.

I do remember dropping my pressures before going out on the track and I got the low pressure warning and even after a session when the pressures reached ~42psi, the low pressure warning stayed on. It actually didn't clear until the next day even with the pressures corrected. That was another reason I trust my gauge over the TPMS but hey, to each their own.

Raising the psi well above 40 and then dropping to the correct psi reportedly accomplishes a TPMS reset (or, as you did, turn the car off and go to sleep).

 

[D.J.]

I always use the tire pressure on the sidewall of the tire……

seriously?

 

[nhcowboy28]

seriously?

Part out

 

[G-710971]

seriously?

got to be a joke, no one is that dumb

 

[Ozstung]

I recently had 32 psi as my starting pressure and no warning.

Raising the psi well above 40 and then dropping to the correct psi reportedly accomplishes a TPMS reset (or, as you did, turn the car off and go to sleep).

Mine comes on at 34psi.

 

[MerlintheMad]

Mine comes on at 34psi.

Makes me wonder if Down Under TPMS brand is different than what's used up here.

 

[antsGT]

I bought an accurate digital tyre pressure gauge, as I was getting frustrated that the TPMS would show different values across all 4 tyres - and I learned that the garage tyre air system was not at all consistent. I have almost certainly spent far too much time worrying about this, but I want the fronts to be 37 and the rears 39 - when cold. This typically means when in use they will be measured at 39 on front and 41 on rear. Trying to set 37/39 when cold just didn't work as the airline wasn't consistent, so I would instead overinflate to 41 front and 43 rear with the tyres warm, and then slowly release air using mu digital gauge to get 39/41 -my ideal running temp. When cold the TMPS reads 37 and 39, the result I wanted... OCD anyone? haha ...but the airline was sometimes 2psi out from one tyre to the next, so it can not be trusted. When letting air out, the smallest hiss can be 0.5psi.

 

[turboAWD]

Yes, the manual calls for 36/39 F/R but that's for stock size/load index.

You still haven't shared which specific tires are in question.

Where do you get 36F / 39R? Are you RWD? Or did yours come with 225 square all seasons?!?

My AWD doorjam placard says 38F / 36 R for the stock 225/255 staggered setup.

Edit: Oh, I see you're GT-Line.. I guess those are different..

 

[antsGT]

I am on my 2nd set and have Michelin Pilot Sport 4S 225/40 19” front and 255/35 19” rears… I am in Australia and my GT is RWD. I forgot to add earlier that they have worn perfectly evenly, so I think my running 1 or 2 psi higher than the door jam has been good. I got 23,000km from that set, 28,000km from the factory fitted Pilot Sport 4. Was looking to get another set of PS4S, but they are very expensive- so I am now thinking of trying Pilot Sport 5 instead.

 

[D.J.]

Was looking to get another set of PS4S, but they are very expensive- so I am now thinking of trying Pilot Sport 5 instead.

Are the PS5's cheaper than the PS4S's

 

[antsGT]

Yes in theory - pricing and availability is uncertain though. With the reading I have done the PS5 is their latest generic performance tyre, with similar but a tiny bit less performance than the PS4S, but way better than the PS4 - but far superior life performance expectancy, and hopefully I will find them available at much cheaper than the PS4S. I need to replace my tyres in the next week so wish me luck!