Hello everyone, Im new here on BITOG and have a question about which fluid to run in my 1997 4l60e transmission. I know the factory fill was a DEX3, but Ive been thinking about switching over to a DEX6 or similar synthetic fluid (Mobil 1). The Truck has 160,000 miles on it, and i did a fluid and filter change on it about three years ago with Castrol dex/merc fluid. Ive been searching around here the last few hours and found plenty of info, I just cant seem to make up my mind. Ive read that the DEX6 is a lighter viscosity oil than the DEX3. Ive also read that Mobil 1 syn. is closer in viscosity to DEX3. I would think that i want to stay as close to the viscosity of a dex3 as i can because that's what the truck is used to. Ive also stumbled upon people recommending the use of Valvoline Maxlife ATF in an older transmission like mine. I just dont want to change to synthetic or DEX6 fluid and have the trans go south. Please someone steer me in the right direction.
Should i make the switch or should I stay with good old dex/merc?
What fluid does everyone recommend i use?
Thanks
-Kyle
Should i make the switch or should I stay with good old dex/merc?
What fluid does everyone recommend i use?
Thanks
-Kyle
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