Trans fluid for a built trans?

[Dozerboy]

Been a while since it was discussed it seems and I can't find a straight Dex3 anymore. What's recommended for a truck used only for towing and spirited driving on the weekends? 600hp and Suncoast if it matters. I see the common Allison fluids are available, but everything else seems to be a Dex/MERC fluid.

 

[KyleC4]

Years ago a guy at GM technical assistance center told me that Dex 3 is still offered but it’s sold as Manual Transmission and Transfer Case fluid. I don’t recall the part number for it though. They kept formulating it cause Tremec said they only wanted Dex 3 in their transmissions. I think some transfer cases as well still call for it. But I know most people will see red fluid drain out and just pump Dex 6 back in just cause they know it’s not Auto Trak fluid. Last service I did at home for a customer I used that new Transynd formula 668 I think. Napa had a deal on it in gallon jugs and it came out to less than $7 a quart

 

[Chevy1925]

Been a while since it was discussed it seems and I can't find a straight Dex3 anymore. What's recommended for a truck used only for towing and spirited driving on the weekends? 600hp and Suncoast if it matters. I see the common Allison fluids are available, but everything else seems to be a Dex/MERC fluid.

valvoline Dex/Merc is Dex3. Mike told me that years ago and its all i used in the truck after.

 

[BoiseRob]

Schaeffer's 204SAT AllTrans is full-syn DexIII. I verified with MikeL that it was a good fluid to use in his trans that was installed in 2019...

All-Trans Supreme® | Schaeffer Oil

Schaeffer's ALL-Trans Supreme is a superior alternative transmission fluid to Dexron III, Mercon, Mercon V, and Allison C-4 type fluids.

www.schaefferoil.com

https://www.schaefferoil.com/documents/90-204SAT-td.pdf

 

[Bdsankey]

I've run anything that is Dex 3 approved and they don't really seem to care. Mike's direction to me awhile back was "what ever the hell is cheapest at the parts store as long as it says Dex 3 you're golden". That advice hasn't let me down yet.

 

[gmduramax]

valvoline Dex/Merc is Dex3. Mike told me that years ago and its all i used in the truck after.

That’s what I run and the clutches looked good after years of 1000hp. But not really sure if fluid makes that much of a difference

 

[Dozerboy]

valvoline Dex/Merc is Dex3. Mike told me that years ago and its all i used in the truck after.

I just found this at Walmart for $18 a gallon. While I hate Walmart and it might not be the boutique brand I'll take it. NAPA has is listed for $22 if yall hate Walmart more then I do.

 

[Chevy1925]

That’s what I run and the clutches looked good after years of 1000hp. But not really sure if fluid makes that much of a difference

He told me, synthetics are too slippery and would cause more wear on c3's. now the last time i talked to him about that was like 2015ish or when ever the G3 clutches came out because we were mulling around the idea about running a different fluid in the truck for the G3's. He just had a worry it would kill the red Alto's sooner that were still in the rest of the trans. Things have clearly changed since then. id bet a synthetic isnt as big an issue anymore but i dont know enough. @Evan@InglewoodTrans would know.

I just found this at Walmart for $18 a gallon. While I hate Walmart and it might not be the boutique brand I'll take it. NAPA has is listed for $22 if yall hate Walmart more then I do.

sweet! im all for the cheapest place i can get oils. i think a gallon of Dex3 was 30 bucks at oreillys last time.

 

[1FastBrick]

Walmart is usually hands down the cheapest for oil's.

I haven't purchased oil or trans fluid from a regular parts store in probably 12 years.

 

[Bdsankey]

I think fleet farm is around $14/gal for Fram branded dex/merc. The last cash and carry build we did that is the fluid they used. Seems to be holding up well.

 

[JoshH]

Literally any generic dex/merc fluid will work. I buy it in bulk from a local oil supplier in 55 gallon drums.

 

[Dozerboy]

Literally any generic dex/merc fluid will work. I buy it in bulk from a local oil supplier in 55 gallon drums.

Shhhhh.... Don't talk like that the diesel bro's will hear you. Seems like some guys think if it's not the most expensive thing out there it's not any good.

 

[Bdsankey]

Shhhhh.... Don't talk like that the diesel bro's will hear you. Seems like some guys think if it's not the most expensive thing out there it's not any good.

^Isn't that sad?