[glxgt]

Tremec says NEVER put anything synthetic ,(even if ATF!!), in these trannys ! No mater what redline and amsoil say- synthetic will destroy carbon parts in tranny...got this from head field tech/inspector him self, its the 1st question he asks when tranny fails!!!

[Fordgazm]

whats made out of carbon inside a tranny ?

[FoxChassis]

I believe the blocker rings are made of carbon fiber.

[T-5 Richie]

I've also heard of good old smelly 90# destroying the fibered linings of the synchros. Well then, exactly what is the proper gear clinging lube to use in these WC boxes? And will it last 100K or must it be changed at certain intervals?

[83GT]

ATF? I put brake fluid in mine so that I can slow down faster without hitting the brake, you know, "brake fluid". My tranny must be old cuz I have to keep adding about a quart every other week or so.

[Jim B]

I've used Mobil 1 Synthtic AFT in my T5's for years. I've had not problem with them at all. I've had one of them apart to fix a bad 5th gear syncro
and the box looked like new.

[Mike Kievit]

Castrol Mercon V. Semisynthetic. I guess I'm bad. Ford says don't use Mercon V too.

44K on the tranny with 31 of it using the Castrol.

Oh well.

MK

[snakepit]

Thanks for the information, I was thinking of using AMSOIL in my trans, but for now I guess I will avoid changing the fluid.

[Mike Kievit]

I change the T-45 every 10 to 15 K. Or after track events.

Oil is cheap.

[crazycarnut]

that is true oil is alot cheaper then a new tranny.