Manual Transmission Fluid
Thread Starter
Burning Brakes
Joined: Feb 2011
Posts: 849
Likes: 0
From: Woodland California
Manual Transmission Fluid
Two months ago I had the fluid in my 6 speed transmission changed.
The guy put in 5-30 weight Mobil 1.
The transmission didn't shift very smooth and it ran hot.
You could feel the warmth in the back cup holder.
Two days ago, after doing 2 weeks of research I decided to switch to Amsoil MTF and Prolong transmissions treatment.
I've had good luck with the Prolong in a 280z I had a few years back.
The shifter boot was off for a time exposing the top of the tranny.
It ran so hot that you could not keep your finger on one of the bolts.
After just the Prolong treatment it was just warm.
After the Amsoil and Prolong treatment in my 6 speed it is much better.
She shifts much better plus it's much quieter plus it runs cooler.
There were a couple of other choices.
Pennzoil Syncromesh, the GM replacement oil and there is one other that I can't think of right now.
But so far so good. We put on about 300 miles the car today and I believe it just keeps getting better.
I hope this helps someone else.
Ralph
The guy put in 5-30 weight Mobil 1.
The transmission didn't shift very smooth and it ran hot.
You could feel the warmth in the back cup holder.
Two days ago, after doing 2 weeks of research I decided to switch to Amsoil MTF and Prolong transmissions treatment.
I've had good luck with the Prolong in a 280z I had a few years back.
The shifter boot was off for a time exposing the top of the tranny.
It ran so hot that you could not keep your finger on one of the bolts.
After just the Prolong treatment it was just warm.
After the Amsoil and Prolong treatment in my 6 speed it is much better.
She shifts much better plus it's much quieter plus it runs cooler.
There were a couple of other choices.
Pennzoil Syncromesh, the GM replacement oil and there is one other that I can't think of right now.
But so far so good. We put on about 300 miles the car today and I believe it just keeps getting better.
I hope this helps someone else.
Ralph
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Joined: Aug 2001
Posts: 5,364
Likes: 38
From: King George VA
Thanks for the update Ralph.
For those interested, this is the product he mentions:
AMSOIL Synthetic Synchromesh Transmission Fluid (MTF) (Product Code MTFQT)
For those interested, this is the product he mentions:
AMSOIL Synthetic Synchromesh Transmission Fluid (MTF) (Product Code MTFQT)
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AMSOIL Preferred Customer Program (Members buy at Wholesale - a savings of about 25%)
Drifting
Joined: Dec 2007
Posts: 1,329
Likes: 17
From: woodbury new jersey
ya your not supposed to use just regular 5w30 motor oil. the gm stuff is 5w-30 but its made specific for the transmission. i used the castrol 10w-60 from bmw for a while, but then switched to the amsoil because i felt like the castrol made shifting tougher in cold weather. it was a much thicker fluid then the amsoil
Race Director
Joined: Nov 2003
Posts: 12,221
Likes: 446
From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
Alex Trebec, I'd like to rephrase my answer in the form of a question! 
I'm using Amsoil MTF but I don't remember the Prolong part. Is that part of the name or something else?
I'm using Amsoil MTF but I don't remember the Prolong part. Is that part of the name or something else?
Race Director
Joined: Nov 2003
Posts: 12,221
Likes: 446
From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
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