Pit-Pony

After 5 months and 10,000km, my rear tire was running low on air. The dealer changed out the TPMS valve stem, said it was leaking.

The next day tire was again down to 11 psi. Went back. They spent an hour screwing around with a soap spray bottle looking for the leak. They could not find one and sent me away.

I was annoyed as the tire was leaking and they couldn't fix it so I was on my own.

I located a tire shop that still had a dunk tank. In 10 seconds the leak showed up as a pin hole in the flat portion of the rim. The rim is otherwise perfect. No dents, no rash, no issues on the edges, just a pin hole not a crack, on the inside flat portion.

I went back to the dealer, third time in two days to get the rim replaced under warantee. First they didn't believe it, than when I showed them the leak by spilling a glass of water on the rim area all they said was, oh ....

So a new rim will take two weeks to arrive. In the mean time they propose using some JB weld on the inside of the rim to stop the leak as a temporary fix. I have no idea if this will work.

I'm picking up the car in the morning, we'll see if this temp patch works.

The thing is, examining the inside of the rim, there are lots of small pin size little holes/defects in the casting.

My conclusion is that the MB OEM rims are pretty crappy on casting Quality Control and are probably just as poorly made as any aftermarket Chinese rim.

Pickles

A most annoying problem....glad you're getting it fixed.
But, I disagree with your last line....manufacturing defects can occur anywhere.....but it doesn't mean to say that the product, as a whole, is crap.
Cheers, Pickles.

antman0505

I had some very fine pits on the polished surface of one of my rims (18"). They were so fine that I didn't see them till I washed the car for the 1st time.

The dealer looked at the rim when I next took the car in (for rattles in the dash), they took some photos which were sent off to MB AUS. The verdict was that the rim needed to be repaired. The rim was sent to the repairer but they couldn't fix it as they said it was a casting fault. Ended up getting a new rim.

Fung63

unfortunately sometimes even the best quality systems will fail. IMO the oem rims are pretty good. The amount of wheels MB pushes through is staggering so statistically, some will fail... unfortunately you happen to have one that did.

What is important here is that MB owned up to it and will replace it for you. GL with replacement!

Pit-Pony

The failure is unacceptable.

It's not just a blemish of some rough finish, but rather a hole right through the wheel that caused a flat.

I doubt they test the wheels under pressure.

justthebest

Just have to say that a 15 second (max) pressure test probably wouldn't have caught the pin hole

Pit-Pony

When I took the wheels to a tire shop with an old fashioned dunk tank, we saw the air bubbles from the rim right away.

The dealer could not find it working on it for an hour or more.