I had a slow leak in my Bridgestone potenza and just kept filling it up about once a week. Then a couple days ago I leave my driveway and it's almost totally flat with around 9PSI. I immediately bring it to the gas station, put air in it, and drop it off at the mechanic.

He calls me later after plugging it and says it's good to go. I get it back and it turned out it had about a 2.5 inch nail in it and he gave me the nail. The next morning I check it and the pressure was back down to around 27.5 PSI from 32. I had to drive it around 6 miles both ways to and from work and when I checked it after I got home, it was at 31 PSI. Naturally it went up from warming up, but then later on it was at 33.5 PSI. Why did it go up again when the tire wasn't used?

Anyway, this morning I'm back at 27.5 PSI again and was wondering if my tire has been compromised from the nail and also I was wondering if driving with one side under inflated will have a negative effect on my diff. I know you're not supposed to run the spare in the rear and was hoping an under inflated tire isn't the same thing.

I'm really hope it has another small leak and that it doesn't need to be replaced cause it has a lot of tread left on it and I don't want to shell out around 200 bucks to replace it. Thanks, guys!

 

27.5psi one morning, 27.5psi the next morning, sounds like you're good to go after you pump it up to 32 cold. Check pressures (all around) regularly.

 

It dropped from the previous 32 cold though. The others haven't fluctuated.

 

This is very simple: inflate all tires to 32psi cold. Monitor pressures. If there is still a slow leak, either add pressure as needed, re-repair, or get a new tire.

 

That's what I was doing, I was also curious to know if it could be repaired again or if it didn't take the first time that it meant I needed a new tire, so I guess it can be rerepaired.

I was also curious about the diff.

 

If they plugged and patched the tire and it is not holding air I would say get a new tire. The difference in the psi could have been they did not air it up correctly or they tires were hot when they checked the psi. Set them cold in the AM before driving on them at all. Driving to a gas station with up the psi.

 

I would also consider having one of those little compressors that plug into 12v power. They have saved my butt a couple of times until I discovered I had a crack in my wheel. Fortunately the wheel crack could be welded and polished cheaper than the tire could be replaced. No more low tires.

 

My tire seems to be okay now. All of their PSI's are fluctuating. It's strange that they all change at different rates and I'm not exactly sure if you can get a true "cold" reading when the temp is mostly between mid 80's and 90's.

It doesn't seem to be losing air now though and that's my main concern.

 

I had a tire that would go low, but only after driving faster than 75 mph. Drive under that speed and the tire would not lose any air, Yep bad valve stem. At hi speed it would bend and leak air, new valve stem all is good.

ROD