L31MaxExpress
I'm Awesome
Problem with the Dex VI is it is low viscosity garbage. Our transmissions were not designed to use it. My transmission builder friend is seeing all kinds of bushing/needle bearing failures that damage hard parts in transmissions running Dex VI. GM has a TSB that supercedes earlier fliuds to DexVI. GM is in the business to build and sell new vehicles, not keep 20-25 year old vehicles on the road another 10 years. I'll stay with Dex III equivalent, I use Valvoline myself.Good point, and a good reason to stick to the recommended GM fluids IMO.
Using Dex VI in these well worn transmissions is equivalent to putting 0w16 in the engine and hoping for the best. Some may get away with it, but some are going to fail.
Nearly 20 years ago Nissan tried the same low viscosity junk in their 5spd FWD transmissions to eek out better CAFE mileage. Maxima, Altima and Quest all had a rash of 5spd transmission failures, before the CVTs were introduced. Basically any transmission that used Matic-K low viscosity fluid was failing.
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