Customs 1955 Cadillac hydra-matic what fluid??

Ok folks I have a 55 Cadillac 331 hydra-matic combo im stuffing in a 56 Cadillac coupe. It's time to start filling up fluids. The fluid that came out of the tranny was clean but didn't look like dex/merc . Ive been having trouble scaring up info on what people are using. I posted on the hamb Cadillac cruiser page and one Cadillac brethren posted back that he is using b&m trick shift ( thank you). I saw one other post on the internet were a guy said dex/merc is fine to use . Can anyone confirm that? I dont know squat about trannies, thanks for any help.

 

I've used Dexron in mine but have Type F in it at present... supposedly shifts better and leaks less.

 

Used whatever version of Dexron that was available during the entire time I drove my 55 Olds, with hydro. Still works fine, since 1982.

 

Alright guys thanks for the help. With that type F do you notice a difference? Warbird1

 

I use Dexron III in my hydros. (All single coupling types like you have). The type F fluid has more abrasives in it and some of the friction components might wear a little faster than with Dexron III.

 

Alright d2willys thanks for the heads up . Ill go with the dex 111. Keep it simple. Thanks again every one

 

I ran type F in my 4sp. hydramatic after an overhaul. Operated perfectly.

 

Nope, never noticed any difference with the Type F in my single-range clunker. I'll probably go back to Dexron when I install the rebuilt Olds dual-range in my roadster.

 

I run Dexron III/DexMerc in my dual range Hydra-matic... 11 years, 80k+ miles no issues.

 

I have a 1950 hydramatic (1950 cadillac 331) and I use Dexron VI. I mustve called 6 cadillac dealers to see if they could verify an article I read claiming theres a service bulletin stating all modern dexron's are compatible with all previous generation dexrons. Not surprisingly none could answer, but I got a hold of an older hyrdramatic rebuilder/specialist who told me the VI would be fine. So far everything seems just fine.

I do believe I read the VI has a stronger shear capability designed for the tighter tolerance modern gm transmissions. I think it might be more like comparing synthetic to standard. Seemed to leak a little at first but that went away. The car has been parked for many years and is just waking back up. Good luck. I think you'll be fine with III or VI.

 

Using Dexron III in my Jetaway, after a fresh rebuild.

 

Thanks every body

 

Great conversation, just getting ready to purchase my 12 quarts for my 55 Hydraglide 4 speed.

Love to be part of this crowd on Jalopyjournal, always good stuff.
HB