Best manual trans. fluid?
Thread Starter
Melting Slicks
Joined: Jul 2006
Posts: 2,094
Likes: 5
From: The 7th layer of hell - Western Washington
Best manual trans. fluid?
I have heard that Royal Purple makes the best fluid for the manual trans in my 02 Z06, and plan to go with the Synchromax® Manual Transmission Fluid. Any feedback on your experience with this fluid? Thanks in advance!!!
Team Owner
Joined: May 2001
Posts: 36,836
Likes: 244
From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
Originally Posted by leadfoot4
I'm using RedLine's ATF. I've had it in my car for 4 years, and I'm happy with it.
I noticed smoother shifting after about a week or so.
Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
fluid
I read a report (im nosey) that was sitting on the service writer's desk when I was in the chevy dealer picking up my car that outlined fluids specific problems.
1. use only GM spec fluids because of lubricity problems
2. use only GM spec fluids because of thermo drag coefficient
properties (when hot, some oils thin out and the synchros don't slow
down for proper gear engagement)
3. use only GM spec fluids because the testing performed with these
fluids made the engineers modify certain parts for compatibility issues
with seal materials, corrosion inhibitors, and water absorption
but what the heck do I know, i just read a lot
1. use only GM spec fluids because of lubricity problems
2. use only GM spec fluids because of thermo drag coefficient
properties (when hot, some oils thin out and the synchros don't slow
down for proper gear engagement)
3. use only GM spec fluids because the testing performed with these
fluids made the engineers modify certain parts for compatibility issues
with seal materials, corrosion inhibitors, and water absorption
but what the heck do I know, i just read a lot
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Team Owner
Joined: May 2001
Posts: 36,836
Likes: 244
From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
Originally Posted by coupeguy2001
I read a report (im nosey) that was sitting on the service writer's desk when I was in the chevy dealer picking up my car that outlined fluids specific problems.
1. use only GM spec fluids because of lubricity problems
2. use only GM spec fluids because of thermo drag coefficient
properties (when hot, some oils thin out and the synchros don't slow
down for proper gear engagement)
3. use only GM spec fluids because the testing performed with these
fluids made the engineers modify certain parts for compatibility issues
with seal materials, corrosion inhibitors, and water absorption
but what the heck do I know, i just read a lot
1. use only GM spec fluids because of lubricity problems
2. use only GM spec fluids because of thermo drag coefficient
properties (when hot, some oils thin out and the synchros don't slow
down for proper gear engagement)
3. use only GM spec fluids because the testing performed with these
fluids made the engineers modify certain parts for compatibility issues
with seal materials, corrosion inhibitors, and water absorption
but what the heck do I know, i just read a lot
My trans remains trouble free and smooth as ever, but what the heck do I know? I just shift a lot.
Le Mans Master
Joined: Aug 2002
Posts: 8,222
Likes: 0
From: Norfolk VA
M1, Redline, AMSOIL and Royal Purple all make good stuff, some people will swear by 1 and say the others are junk and they all have test data to show that they are the best. I wouldn't worry about putting any of them in my car. I've got RP in there now because it's sold locally so it was the easiest to get.
Advanced
Joined: Feb 2006
Posts: 97
Likes: 0
From: Miami/Ft. Lauderdale FL
My tranny used to grind real bad going into 2nd 3rd and 4th at high rpms (above 5500)..
I tried mobil 1 atf... no good still grinding
gm synchromax.... no good still grinding
right before I was about to order a new tranny i tried royal purple since i finally found it locally.
Guess what?
Tranny shifts like butter into every gear even at 6200 rpms!!!!!!!!!!!
Royal Purple Synchromax hands down.
I tried mobil 1 atf... no good still grinding
gm synchromax.... no good still grinding
right before I was about to order a new tranny i tried royal purple since i finally found it locally.
Guess what?
Tranny shifts like butter into every gear even at 6200 rpms!!!!!!!!!!!
Royal Purple Synchromax hands down.
Drifting
Joined: Dec 2005
Posts: 1,720
Likes: 3
From: East Hampton CT
Originally Posted by RickC5
My tranny used to grind real bad going into 2nd 3rd and 4th at high rpms (above 5500)..
I tried mobil 1 atf... no good still grinding
gm synchromax.... no good still grinding
right before I was about to order a new tranny i tried royal purple since i finally found it locally.
Guess what?
Tranny shifts like butter into every gear even at 6200 rpms!!!!!!!!!!!
Royal Purple Synchromax hands down.
I tried mobil 1 atf... no good still grinding
gm synchromax.... no good still grinding
right before I was about to order a new tranny i tried royal purple since i finally found it locally.
Guess what?
Tranny shifts like butter into every gear even at 6200 rpms!!!!!!!!!!!
Royal Purple Synchromax hands down.
Le Mans Master
Joined: May 2005
Posts: 6,366
Likes: 249
From: Fort Lauderdale, Florida
I have tried several different fluids in my quest to get smoother shifting. I've used Mobil 1 synthetic, Dexron VI, and Red-Line. I am now using the Royal Purple Synchromax, which is a manual fluid for trans that specify ATF. There was a significant difference right away using Royal Purple. The car now shifts the smoothest it ever has. It seems to get a little better the longer it's been in. Thumbs up on the Royal Purple, it works.
Thread Starter
Melting Slicks
Joined: Jul 2006
Posts: 2,094
Likes: 5
From: The 7th layer of hell - Western Washington
Put the Royal Purple Synchromax in the trans and 75-90 GL in the differential tonight and things feel pretty nice. Can't wait to see how things feel in a week or so when the fluid has had time to "work it's magic".
Le Mans Master
Joined: Aug 2003
Posts: 9,298
Likes: 4
From: American Canyon Lethal Injection
Originally Posted by jbauch357
Put the Royal Purple Synchromax in the trans and 75-90 GL in the differential tonight and things feel pretty nice. Can't wait to see how things feel in a week or so when the fluid has had time to "work it's magic".
Good stuff..........
