First an edit. Should have put Dextron VI. Don’t type Roman numerals much.

scrubrolet lists Dextron VI as a fully synthetic, backwards compatible ATF.

If your hydro is like any I’ve ridden in, you won’t need firmer shifts. They were fairly firm to begin with. And I’m not talking about B&M race units.

miker
55 bird, 32 cabrio F code
Kent, WA
Tucson, AZ

The manual is going to list an obsolete fluid.

First I’d ask the guy that rebuilt it

But if it “says” Dextron, GM says it’s all backwards compatible. Some sources say Dextron IV is the only one they license now, so no Dextrin III can guarantee it meets the old spec.

Confusing huh?

What Mike said, ask the re-builder. It is all going to matter as to what kit and friction materials he used, especially if considering going to a synthetic. He should have specified the type on the shop receipt as warranty is going to depend on it.

- https://fluidadvise.com/dexron-3-vs-4-vs-atf-4/

'TYPE-F' (if you can find actual 'TYPE-F') is going to give a much firmer shift. Save that for HI-PO.

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What about synthetic fluid

Brad
Sierra Vista Arizona
1954 Lincoln Capri

I have always used Type "F" in my '54 Mercury automatic transmission and that should be fine for your Lincoln hydramatic.

The manual is going to list an obsolete fluid. First I’d ask the guy that rebuilt it. But if it “says” Dextron, GM says it’s all backwards compatible. Some sources say Dextron IV is the only one they license now, so no Dextrin III can guarantee it meets the old spec. Confusing huh?

Most of the rebuilders I found are saying just Dextron.

miker
55 bird, 32 cabrio F code
Kent, WA
Tucson, AZ

Do you have the ownersmanual?  It might say something there.

54 Victoria 312;  48 Ford Conv 302, 56 Bird 312
Forever Ford
Midland Park, NJ

Trying to find out what type tranny fluid for my recently rebuilt hydramatic

Brad
Sierra Vista Arizona
1954 Lincoln Capri