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Tire's loosing air

My wife had a accident in her 2004 Mustang on the expressway.The road was covered in snow when she spun around before hitting the guard rail.Both right side tires were almost flat.The body shop put air in them and said nothing was wrong with the tires.Since we got the car back from the body shop these tires keep loosing air,about 7 lbs every few days.I should have brought the car back but kept putting it off.No other problems with the tires.Any suggestions?

Tires may be fine…but there’s a change the rims got bent. Take the tires to a tire shop.

If the tires are losing air ever since the accident, I would strongly suspect that the wheel rims were bent by the impact. Even if the tires themselves were not damaged, bent rims could certainly account for the tires losing air every day.

And, if the impact was sufficient to bend the rims, then it is also possible that there is damage to front end components such as tie rod ends and ball joints.

Two new wheels and some front end work are certainly cheaper than the costs–both human and car-related–that could result from another accident.

This is a safety issue.
Don’t put this off any longer unless you want to hear that your wife had another accident with that car.

Car drives straight,no wobble or vibration.

Probably the wheels were bent, as the other posters have mentioned. Another possibility is that the valve stems were damaged. Take a wheel off and spray the bead and valve stem areas with soapy water. With a leak that big, you should see bubbles right away.

I hope you have good winter tires on the car already. If not, please get some now. A Mustang in the snow really isn’t safe without winter tires.

If the tires went flat due to the spin out, then the wheels and tires came into contact with something, likely the guard rail. The beads on the tires and/or the edges of the rims were damaged or perhaps just have dirt and debris imbedded in there and not sealing completely.

Take the car to a tire shop and have the tires dismounted from the wheels and inspect the tires and wheels for scratches, dirts, and gouges. There can be debris in the valve stem area too, so have the old valve cut out and replaced. If all cleans up OK have the tires mounted and balanced again and you should be all set. If some hidden damage is found you can contact your insurance company, replacement wheels are pricey.

“A Mustang in the snow really isn’t safe without winter tires.”

A neighbor of mine illustrates this every year with his Mustang!

He always seems to bog down on the exact same corner every time we have a significant snow accumulation. While driving ability definitely has something to do with this problem, you would think that he would have learned by now that his RWD car desperately needs good winter tires.

Your description does not mention the car leaving the paved surface, but if it did, check for dirt between the bead and the rim. This happened to my daughter’s car when she slid off an exit ramp one rainy night.

Also possible to have cracked rims even if they don’t appear to be bent.

You seem to disbelieve bent rim becuse car does not wobble or vibrate. A small bend – a lttle downward curl – on the lip of the rim, where the tire bead seals, is enough to cause a leak, but the tire/wheel will still run fine. Sometimes such a bend can be straightened. The one I experienced was on the INSIDE of the rim on a car handed down by Dad. (How did he do THAT???)

She did slide off the roadway into a grassy area before hitting the guardrail.The guardrail was one of those with cable,not solid steel.All of the damage was cosmetic such as the bumper cover,headlight and right front fender.I think she hit it twice because the rear bumper cover was also damaged.
The rims and tires were off my 04 gt…Couldnt afford tires at the time so I put my rims on her car.Have since bought winter tires for her car.

That means NOTHING. I’ve seen bent rims that don’t wobble or vibrate at all…Take it to a tire shop.