I see a lot of questions on here asking about what trans fluid should be used in the t-56. I called up Tremec technical support to get the final answer.

-Dexron III is THE most highly recommended all round choice, specifically Texaco/Havoline brand.

-Dexron VI- Still being evaluated and tested, NOT recommended for the T-56 at this time and has caused issues so far in preliminary evaluation.

-Syncromesh- Not really recommended, but can be used in high temp high stress applications(drag racing, very hot climates etc.) since it is thicker than dexron III for some added protection.

-Synthetic- Mobil 1 is the only brand advisable to use and tested by Tremec, can cause shifting issues in colder climates.

So there you go, straight from the manufacturer.

 

Yeah, Mobil1. They rock.

 

I personally use Synchromesh, made a huge diff over stock fluid, I highly recommend

 

Royal Purple isn't recommended by SixSpeeds Inc

I've run regular, Mobil 1 and Amsoil in my transmission and found regular felt a bit more notchier when cold.

Mobil 1 and Amsoil feel about the same and both come out looking pretty damn clean at each change that I may just keep it in a bit longer than I've been doing.

Syncromesh is used by a lot of people here with good results, I'd say go with regular off the shelf unless you find a significant improvement with synthetic or syncromesh in how it feels.

 

Per Six Speeds Inc's recommendation, I'm running Redline ATF this year since she'll see the track a lot.

is it 3.5 or 4 quarts?

 

goddamn you think its notchy when cold I gotta turn off my car sometimes and start it.. just bled clutch and did some generic DEX III going Mobile 1 now... is it bottle labeled Mobile 1 ATF?

 

yeah my car shifts real bad when it's cold. what fluid would be the best for cold weather shifting? I always thought the synthetics like Mobil 1 was better for the cold weather??

 

I got DEX III from dealer.

 

The tech guy from Tremec SPECIFICALLY told me that synthetics can cause hard, notchy shifting in cold weather. He suggested NOT using synthetic if you live where it gets cold often.

 

And this is coming from the same people that designed the T3650 in the Fords that has a huge known problem with the 3rd gear syncro ring and also the makers of the TKO500 & 600 units that are literally hit and miss with shifting issues .

I've used RP syncromax in a crap load of T5's and T56's with ZERO issues . Its a little slicker than non synthetic ATF but cuts the heat in half for extreme conditions that a lot of folks down here in south Texas deal with in the middle of the summer . Take that for what its worth ....

 

I have always used ATF with Ford Friction Modifier in every manual transmission I have had. T5, Tremec3550, 3650 and TKO600, T56.

 

What ever u do DONT put Royal Purple in there. That fucked my **** up. Now i use mobil 1 ATF!

 

I run RP and it shifts a little hard when the fluids cold, but other than that 15K miles and no problems.

 

Havoline has a few automatic transmission fluids available.. i am guessing we should use the MD3 in our T56's??

http://www.havoline.com/products/na/transfluids.html

 

Please do tell me how RP destroyed your transmission ....... I would love to hear all about it .

 

well 6-speeds inc recommends Mobile 1 ATF in the tranny's and i dont think mobile makes a non syn and dont think they would be running crap

 

Probably off-topic, as this has to do with breaking in a freshly rebuilt T-56...

 

Oh yea u forgot the part out about no downshifting for the first 500 miles. And "t56rebuilds" now called six speeds inc built my tranny. They told me NOT run rp in my tranny. The additives in it eats the fibers off the blocker rings.Simple as that. So all the people that run rp in their tranny i hope you got about 1000 bucks laying around.

 

"Oh yea u forgot the part out about no downshifting for the first 500 miles. And "t56rebuilds" now called six speeds inc built my tranny. They told me NOT run rp in my tranny. The additives in it eats the fibers off the blocker rings.Simple as that. So all the people that run rp in their tranny i hope you got about 1000 bucks laying around."

Ummmmmmmmm............none of that was on the break in instruction sheet that came back with my tranny. What I have read, is that Royal Purple Synchromax, Mobil 1, or any other synthetic ATF DOES degrade OEM T56 internals. When OEM internals are replaced by upgraded, aftermarket internals, synthetics are actually recommended. I'm looking at product literature from AMSOIL right now. The product lookup header reads "2002 PONTIAC FIREBIRD 5.7L 8-cyl VIN Code G. Under "LUBRICANTS & FLUIDS, MANUAL TRANSMISSION", AMSOIL specifies 2 of their synthetics; Synthetic Automatic Transmission Fluid, and Torque-Drive Synthetic Automatic Transmission Fluid.

I stoked mine with Royal Purple after it was rebuilt, and had no problems. BTW, I was not aware that t56rebuilds.com had changed their name to six speeds inc. I'd be happy to zap off a copy of the t56rebuilds.com break in instructions, and send it to you.

 

Royal Purple was previously recomended by us,(more than 2 years ago) but in light of some new info from Libertys Gears, we no longer recomend Royal Purple. Royal Purple has and additive in it that attacks the blocker ring material, and it thins out/ breaks down toward the end of it life cycle. This is not a test that we have done in house, but Liberty Gears, placed a blocker ring in a container filled with Royal Purple , and one in Mobil 1, and after several weeks they noticed that the carbon material from the blocker ringn in Royal Purple started to deteriate. This test was performed several years ago. As a side note I use Royal Purple in my race engine