Tire problems, 1 bubble, 1 losing air. Help..

[Bmw 325i 7803]

After driving 350 miles yesterday, I noticed this evening that my right-rear tire has a minor bulge or "bubble"(its not really sticking out much) in the sidewall. I keep the tire pressure at 32-34 in the front and at 42-44 in the rear. Is this covered by warranty since the tires have 28k on them and are OEM from when I bought the car over 2 years ago.

Also my left-rear tire seems to lose 15lbs of pressure every day if I drive the car, or 6lbs of pressure if I let it sit. Some days it doesn't lose any pressure, other days when it rains especially, it looses maybe 20lbs in a day.... Is it a valve-stem leak? I have no idea what's going on. Also, both of the rear tires have about 60-70% of the thread worn...

 

[Bmw 325i 7803]

bump....(well it is a sunday morning)

If I were to swap the tire with the bulge to the spare in the trunk, would that compromise handling in the rain at say speeds of 75mph, since i'd have one tire which slightly loses air with 70% thread wear, and another tire on the otherside with 0% tread wear.

 

[squarehat]

I had a sidewall bulge develop on one of my OEM Continentals last month (probably only had about 14K on it, since I had snow tires on for five months). Unfortunately, it wasn't covered under warranty, so I spent $109 part and $42 labor on a matching replacement.

15 psi in one day?! Have you had that tire checked for nail holes, etc? I thought it was bad when a couple of tires on my old Lexus lost 10 psi a month. They should be able to check the valvestems by spraying them with soapy water and looking for bubbles.

 

[Bmw 325i 7803]

The local tire shop thinks the bulge resulted from a pothole so I decided to use that tire as my trunk spare. The tire which was losing air had a nail in it, that got plugged which supposedly should last forever. So the side which had the leaking tire now has the brand new spare on it, and the side which had the bubble has the old-plugged tire on it now.

So for $25 I got my tires taken care of, and one tire has more thread than the other on the rear, which hopefully is not an issue.

 

[Kirby]

I wonder if you might have problems with DSC kicking in. Other people have had such issues because DSC can interpret the difference in wheel RPM as slippage. The "new" tire with no wear will spin at a bit slower speed than the worn (smaller diameter) tires.

 

[Bmw 325i 7803]

So far no DSC issues, I'm just curious if I am cutting that one tires life, since it's less worn than the rest, or If I'm going to experience handling issues in the snow...

 

[Average Jae]

just curious what tire set up you have. do you have the same size all around? or staggered? and what of the spare? are they doughnuts?

it sucks you ran into that issue, but am glad that you sort of found a solution.

i always figured with different tread wear on the left and the right, the balance might be thrown off, so your car may always lean to one side with less tread wear. (but that's just what i figure and my theory, so who knows.)

but if i were you, i would actually dump the tire with the bulge, as that's an indicator of a jacked up sidewall, meaning not very safe. purchase a new tire that matches the new spare (assuming it to be a full size spare), so you'd have same tread depth on the other side, and stick the plugged tire as the spare. (this is assuming that you have non-staggered set up, and you carry a full size spare, but from the sounds of what you wrote, that seems to be the case?) anyway since i'm not sure how your car's set up, my opinion maybe way off on the left..

 

[Bmw 325i 7803]

It's a stock setup and the tires are the same size all around. The spare in the trunk is fullsize new tire and rim. It's what is on the left side of the car now. The tire in the trunk has the slight warp. (it's not even a bubble, it's more of a 2-3inch warp in the sidewall where it says goodyear) So far it runs perfect, but I do agree with your idea that I should keep the plugged tire as the spare, and buy a new tire for the right side. The thing is shouldn't that tire be replaced under warranty? I'll figure something out, I also am surprised to notice that the new BMWs and even the economy cars only have donuts, and they don't carry full sized spares like the E46.

 

[squarehat]

I think only the 328i/330i had the full-size spare on a matching alloy. I'm fairly certain my E46 325i is a smaller (though not quite "donut") spare on a "steelie." Otherwise I would have done the same thing (swapped temporarily with the spare) when I found the damaged sidewall on my tire.