Why is the Tire Pressure different between AWD Front and Rear Tires for the GT ?

[NYstingerGT2]

Don’t know if this has been covered but I’m curious why the GT requires 39PSI for the rear tires and 36 PSI for the front . Usually cars have the same PSI for both front and rear tires

 

[MisterMac]

Because the load rating of the tires are different.

The front tires are 93Y and the rear are 95Y.

Inflation is math, determined by the load rating and the weight of the vehicle.

 

[NYstingerGT2]

Oh ok , makes sense but why would the load rating be different if both tires are the same size ? Aren’t the AwD GT tires sames size ?

 

[MisterMac]

You have the 19 inch wheels. Correct? The backs are wider than the front. It's called being staggered.

 

[Robcio]

I have a GT AWD here in Korea and mine shows 36psi all round.

 

[MisterMac]

I have a GT AWD here in Korea and mine shows 36psi all round.

In the USA yours would have the 18 inch tire package

 

[MerlintheMad]

OP: you mean 38 psi in front, not 39 psi.

The rear tires on the staggered 19s wear c. twice as fast as the front tires. That is why all makes of tires only offer half of their listed treadlife warranty: e.g. my Nitto Motivos UHP A/S have a 60K mile treadlife warranty, which means 30K with the 19" rims. But that is incidental to the OP question, which has already been answered. Heh. I guess I am rambling off to bed now ...

 

[MisterMac]

OP: you mean 38 psi in front, not 39 psi.

The rear tires on the staggered 19s wear c. twice as fast as the front tires. That is why all makes of tires only offer half of their listed treadlife warranty: e.g. my Nitto Motivos UHP A/S have a 60K mile treadlife warranty, which means 30K with the 19" rims. But that is incidental to the OP question, which has already been answered. Heh. I guess I am rambling off to bed now ...

Actually, on mine, the fronts are 38 and the rears are 36, which matches the load ratings. The lower the load rating, the higher the psi to support the same amount of weight.

 

[MerlintheMad]

Actually, on mine, the fronts are 38 and the rears are 36, which matches the load ratings. The lower the load rating, the higher the psi to support the same amount of weight.

Oh, good catch. I missed that.

 

[NYstingerGT2]

I have GT2 AWD and my tires are 18 inch back and front . The tire pressure sticker says 39 psi for rear and 36 for front .

 

[MerlintheMad]

I have GT2 AWD and my tires are 18 inch back and front . The tire pressure sticker says 39 psi for rear and 36 for front .

Well! Color me surprised, then. I thought that 18s squared had the same psi front to rear. So naturally, from what you said, I assumed that you were describing 19s staggered, and just got the description backwards. Sorry to add to the confusion. I hate it when I do that.

 

[MisterMac]

I have GT2 AWD and my tires are 18 inch back and front . The tire pressure sticker says 39 psi for rear and 36 for front .

Will you please take a picture of the sticker on your door jamb showing this information. I find this very interesting.

 

[MisterMac]

Here is mine

 

[eflyguy]

Without getting into specifics for every supplied combination, optimal tire pressure can vary for many reasons including handling, fuel economy, longevity, etc. The numbers on the plate are for the tires supplied with the vehicle and determined by a combination of factors I listed. To meet EPA fuel economy targets they would be higher than desired for the best handling characteristics, for example. At race tracks, we adjust by as little as 1/2PSI (I'm sure professionals are even more precise) and it makes a difference.

So even for identical tires on all 4 corners on a street vehicle, the weight balance and handling requirements might have a different front/rear recommendation.

 

[NYstingerGT2]

I am attaching picture from door and also I have the same load size for both tires so to me it’s weird why the recommendation of psi is different for both tires . Also my GT2 AWD has 18 inch tires but I’ve seen some people on here with 19 inch

 

[Ucinn]

Weight difference between front and back more than likely. Probably wouldn't be different if you had a 50/50 weight ratio front to back.

 

[NYstingerGT2]

Oh good point . Maybe that could be it

 

[NYstingerGT2]

Weight difference between front and back more than likely. Probably wouldn't be different if you had a 50/50 weight ratio front to back.[/QUOTE


I’m very curious now

 

[Ucinn]

My reasoning is more weight means more PSI to make the front tires have the same contact patch as the rears, in my mind it makes sense...but....lol

 

[Jaymorz]

I swapped out my OEM AWD 18" tires with Nokian WR G4 All Weather Tires. Trusted tire shop I go to inflated them to 40 PSI both front and rear. They told me Nokian specs recommended PSI ratings for optimal performance based on vehicle weight class and drive train