Lubricant know how needed>>>

[ZR1Vette]

Although this has nothing to do with the ZR-1 (already changed every lubricant to brake fluid thanks to the know how of this forum of recommending what to use )... this is for my C6.

The MY05 C6 has a Tremec T56 tranny (mine also has a B&M SS) and it is time to change its fluid (along with the engine and diff...those lubricants I have finalized), but finding recommendations all over the place for the 6 sp tranny:
-OEM- Synthetic Automatic Transmission Fluid 88861800
-Royal Purple Synchromax
-RedLine D4 ATF
-Amsoil Synthetic ATF
-Amsoil 5-30W Synthetic Manual Synchromesh Transmission Fluid

First, why use ATF in a manual tranny? I am partial to Amsoil products, but really sorta stymied here on what to use. You guys have any observations or experience with this topic?

Appreciated any comments...

Originally Posted by ZR1Vette

The MY05 C6 has a Tremec T56 tranny (mine also has a B&M SS) and it is time to change its fluid (along with the engine and diff...those lubricants I have finalized), but finding recommendations all over the place for the 6 sp tranny:
-OEM- Synthetic Automatic Transmission Fluid 88861800
-Royal Purple Synchromax
-RedLine D4 ATF
-Amsoil Synthetic ATF
-Amsoil 5-30W Synthetic Manual Synchromesh Transmission Fluid

First, why use ATF in a manual tranny? I am partial to Amsoil products, but really sorta stymied here on what to use. You guys have any observations or experience with this topic?

Appreciated any comments...

Tremec designed the T56 to have ATF used in it, and has had ATF in it for quite a while now. I have not looked into what the benefits are for ATF over conventional oil.

But as with a lot of things, people recommend what they use. If you are not in the severe duty category (road racing), the GM fluid is more than adequate. After that it just becomes your personal preference on which is better.

[32valvZ]

I'll add that in my C5Z, I switched from the GM fluid to the Royal Purple Synchromax. I noticed that the shifts were smoother and not quite as "notchy"as before.

[bldavis11]

Originally Posted by 32valvZ

I'll add that in my C5Z, I switched from the GM fluid to the Royal Purple Synchromax. I noticed that the shifts were smoother and not quite as "notchy"as before.

Yeah, but how much of that was due to just new fluid alone? I agree with Jeff. If you are just driving the car and not racing, the GM spec stuff is just fine.