Originally Posted by m5james

You might wanna check out www.noreverse.org.To the OP, I'd go ahead and do a complete flush, or at least a drain and fill. You can use Valvoline MaxLife instead of Esso ($$$) and make sure to use only Filtran filters. I bought mine @ Auto Parts at AutohausAZ - OEM Auto Parts - Discount Replacement Parts, Resources and Car Care Tips, then followed the writeups on e38.org BMW 7-series information and links.