Mishimoto used to make an m54 expansion tank that was all aluminum. The problem is: that tank won't fail, but something else in the chain will if you don't lower the abnormally high temp and pressure our systems run at to get that ULEV certification.


If everything in the system was metal, you would probably have to do hoses more frequently, but your tstat and expansion tank would not be the weakest links in the chain.

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2001 E53 3.0 5pd