Is low rear tire pressure common?

[SVTKen]

Is low rear tire pressure common in our cars? I've owned other high horsepower cars before, and I've never had issues with losing tire pressure in the rear tires. I've taken it to the dealer several times since January, and they say there is no leak. The tech said it's common to lose pressure when you spin the tires, which I have done quite a bit. I haven't had to touch the pressure in the front tires since I purchased the Shelby, but the rears don't hold the pressure. Typically, they get down into the mid to low 20 psi, and pressure is always identical in each of the rear tires when it's low.

Any ideas what's causing this? Anyone else have this problem?

 

[NELCO]

Ken, My 500 has only lost only .5oz. since Oct. 31, 2013.. Have you checked the schraders? Good Luck.
Nelco

 

[SVTKen]

Ken, My 500 has only lost only .5oz. since Oct. 31, 2013.. Have you checked the schraders? Good Luck.
Nelco

I haven't been doing massive burnouts, but I have been spinning them quite a bit. Have you been spinning your tires and still not lost any tire pressure?

 

[NELCO]

Oh Yeah.
Nelco

 

[Myfast70]

My tire pressure has been pretty solid since i got it last Oct. What pressure are you running? There were a couple other guys having pressure issues with the right front (if I remember correctly). Are you running just normal air or Nitrogen?

 

[SVTKen]

I'm running the recommended pressure, about 35 psi all around.

 

[Myfast70]

Have you tried spraying the beads and valve stems with soapy water and looked for bubbles?

 

[Cman01]

I did the post about the RF tire having less air than the rest of them:

http://www.svtperformance.com/forums/2013-shelby-gt500-413/937690-tire-pressure-check-anyone.html

Since I've tighten up the schrader valve inside each valve stem that RF has been ok and all 4 tires are keeping the pressures I set them at.

Tony

 

[SVTKen]

Thanks for the advice guys. I will check out the shrader valve inside each valve stem.

 

[Norton]

I'm not doing a lot of tire spinning, but certainly some, and I've had ZERO problems with rear tire pressure.

On a side note, the problem with my RF tire pressure hasn't cropped back up in quite some time. Re-tightening the Schrader valve SEEMS to have solved the problem. (Crosses fingers...)

 

[eagle eye]

Have you tried spraying the beads and valve stems with soapy water and looked for bubbles?

There's a real good possibility that the leak may be coming from around the bead like Myfast had suggested.
During the winter while I was having the car wrapped with Xpel, the installer had gotten some overspray on the RF wheel and noticed an air bubble coming from around the tire bead. It lost around 8-10 lbs over the course of 8 weeks.
I have also seen air leak from where there's a bar code sticker on the tire bead.

 

[Cman01]

Don't see how spinning the tires would cause a loss of pressure unless it's caused by a puncture or you burnout the tire so much that it explodes, if anything pressure should increase cause of the generated heat from excessive tire spin.

 

[JimIII@jdm]

Spinning the tires or doing burn outs causing loss of pressure is the most ridiculous thing I have ever heard. In fact when you heat up the tires, like you would do in a drag race the tires get hot the air expands and you actually can see another psi or two in the tires from before your burn out to after.

You have a slow leak somewhere, check the valve stems or for a nail/screw

 

[JimIII@jdm]

This is the only way to lose air pressure from spinning your tires.... MUSTANG BURNOUT BURN 'EM TIL THEY POP - YouTube

 

[smrtasp]

If your running the performance pack, those wheels are supposed to have knuckles inside the bead to keep them from spinning. I would try some soapy water around the valve. They can be tightened with a valve tool so maybe its just a bit loose. Losing even a small amount of air is not common.

 

[Kapy]

spinning the tires or doing burn outs causing loss of pressure is the most ridiculous thing i have ever heard. In fact when you heat up the tires, like you would do in a drag race the tires get hot the air expands and you actually can see another psi or two in the tires from before your burn out to after.

You have a slow leak somewhere, check the valve stems or for a nail/screw

++++1

 

[Cman01]

The base wheels have those knurls too not just the pp wheels so that doesn't matter.

 

[Mackey]

I had to have my tire stem replaced in my right front. It was slowly leaking due to corrosion that had built up between the tire-stem and the wheel.

It was covered under warranty. I was losing 4-5PSI per day through the stem. I was able to diagnose the issue by spraying Windex on the stem itself.

 

[Roushman]

My tire light just came on. I checked pressure and all 4 tires read 27.5 on my digital gauge. What pressure makes the warning come on?

 

[Snoopy49]

There is a tag located near the tire bead that has caused at least 1 leak. If the tag is positioned on the bead , it may cause a leak.