Owner reviews for expansion tank

The oem BMW expansion tank has the longest life. I've been thru several aftermarket Expansion tanks that crack much earlier than a Factory BMW brand.

I wound up buying an OEM expansion tank and I don’t regret spending the extra money, especially after seeing the fittings.

i have the febi tank installed on both my e46's and the work fine.

Good news is that none of the sensors leak out from the O-ring seal with the new tank, so I do think there could have been a problem with the yellowed out old tank, perhaps slightly warped/deformed.

Those tanks are cheap and very easy to replace, also if you don't get a lot of air in your system they work just fine. So slap a new one in there and no worries.

Yes, replacing the expansion tank corrected my issue. Leaking or venting from that tank is not normal, if the system builds up to much pressure it should release from the pressure cap.

Mishimoto tank is metal not plastic so it wont crack.

The New Meyle expansion tank for MKIV VW is Made in China. One of the features of this tank is that you get to spend several hours filing and sanding, to get the tank to fit. The plastic tube that anchors the tank has the correct inner thickness. But, the outer thickness is to large, .030 in. bigger. Attempting to install it this way will bend the metal anchor. Since, there is enough material, you can just file down.

Later I noticed a hairline crack in the new expansion tank (FEBI) and that sensor was also acting up.

My experience of running my previous E46 325i (rare manual) echoes what some of the others are saying.

Cooling system components are flakey at best, especially the expansion tank.