Early T3650 fluid?

[Brewkett]

I know this is probably going to be a flame war.
I have a 2001 Cobra with 35k miles, garage kept 3 owner, All factory original.
I want to do some maintenance due to everything is 16 years old....
Reading about the T3650, I've seen reference to early and late builds some with brass and paper lined syncros. I've been told in the past to use Mercon III, but its no longer made, and superseded by Mercon V. I've read the Merc V isn't good on the early trans, and use the syncromesh fluid, but on the flip side I've heard the syncromesh will tear up the syncros. I know there has been a lot of changes in fluids in the last few years.....
Whats the latest goto fluid for the early T3650's? ATF, SYNTH ATF, Syncromesh, AMSOIL, Royal Purple?

 

[01yellercobra]

I ran Coastal brand ATF in my 3650 and first T-56. I think it was the Mercon V. Never had an issue. That trans lived behind a blown big bore stroker. I'm currently running Synchromesh in my current T-56 and it doesn't shift any different than the Coastal.

Misspelling brought to you by Tapatalk

 

[Brutal Metal]

Amsoil ATF is good.

 

[me32]

I've always liked Amsoil ATF or royal purple syncromesh

 

[Brewkett]

On the Amsoil, Do you use the Manual Synchromesh trans fluid 5w30, or the Signature Series Multi Vehicle Synthetic ATF

 

[01BlkSn8k]

I've been using Pennzoil Syncrhomesh for the past 2.5 yrs, I also did the FWA, and the shifts are smooth as butter. It's the MMS FWA Kit

 

[Brutal Metal]

On the Amsoil, Do you use the Manual Synchromesh trans fluid 5w30, or the Signature Series Multi Vehicle Synthetic ATF

Signature Series ATF has versions dating back decades, I always ran it in my T-5's, it's in my T-45 now. The T-56 uses the Synchromesh. If you called Tremec I'm not sure the answer you'd get for the 3650, the Mercon V type SS, or the Mesh 5W30? I know what I like.

 

[shurur]

I think the t45 and 3650 use non-synthetic ATF...castrol or valvoline

Synthetic ATF damages the materials used in the synchro linings and leads to premature wear

 

[Brewkett]

What I got back from Tremec for the TR3650 was Mobile 1 synth AFT.

 

[shurur]

https://www.stangnet.com/mustang-forums/threads/best-trans-fluid-for-the-3650.652677/
post #7

 

[Venom69]

I know this is probably going to be a flame war.
I have a 2001 Cobra with 35k miles, garage kept 3 owner, All factory original.
I want to do some maintenance due to everything is 16 years old....
Reading about the T3650, I've seen reference to early and late builds some with brass and paper lined syncros. I've been told in the past to use Mercon III, but its no longer made, and superseded by Mercon V. I've read the Merc V isn't good on the early trans, and use the syncromesh fluid, but on the flip side I've heard the syncromesh will tear up the syncros. I know there has been a lot of changes in fluids in the last few years.....
Whats the latest goto fluid for the early T3650's? ATF, SYNTH ATF, Syncromesh, AMSOIL, Royal Purple?

My 2001 svt cobra just got hit on the right front side and minimal damage is someone interested I used amsoil

 

[Venom69]

It's a 9/10 car

 

[Snk-Byet01]

I think the t45 and 3650 use non-synthetic ATF...castrol or valvoline

Synthetic ATF damages the materials used in the synchro linings and leads to premature wear

^^^^
What he says. No synthetic and very important not to fill up the t-case. Just 3.2 quarts (3.0 Liters) of ATF. Tremec has a TSB on this issue. For some stupid reason I switched to RP and filled the transmission up to the fill hole. After awhile I could barely shift, especially 2nd to 3rd. I had to drain the $$ RP out, flush with kerosene and refill with plain old ATF. The TSB mentions Texaco-Havoline Dexron III/Mercon Non-Synthetic ATF but I would think most Mercon / Dexron III ATFs would work.

Attached is a TSB from Ford, not Tremec.