Another ZF6 Fluid Thread
Le Mans Master
Joined: Jun 2009
Posts: 6,528
Likes: 752
From: South Dakota
I had an issue with 1st to 2nd gear shifts on my '95. It seemed just a little "notchy" when cold. By that I mean it didn't shift in smoothly, not a grind, but just a click as it went into 2nd. It did not do that once warmed up.
I suspect it had the original fluid. I changed it out to the Amsoil fluid. The "notchy" shifts went away immediately and has not returned for over 5 years now.
My vote is the Amsoil. It improved the shifting for me.
Good luck
I suspect it had the original fluid. I changed it out to the Amsoil fluid. The "notchy" shifts went away immediately and has not returned for over 5 years now.
My vote is the Amsoil. It improved the shifting for me.
Good luck
Race Director
Joined: Sep 2001
Posts: 14,680
Likes: 752
From: NEwhere Ohio
I've done my due diligence reading through the threads on what fluid everyone is using in the ZF6. ZF Doc suggests Castrol TWS 10W60 which does not appear available anywhere. I've read good and bad on the Amsoil synchromesh. Same with the 88900333 GM fluid which is not fully synthetic. I'm a maintenance hog with my 96......so what's the consensus gentlemen? What's everyone using?
zfdoc’s advice is outdated and website un-updated from a time when the original 5w-30 based trans oil (note its not motor oil) was discontinued and modern syncromesh fluid wasnt yet available
some early users of bmw engine oil (10w-60) castrol had decent luck however most havent - esp recently. The guys who have had good luck i suspect are using some early version of castrol 10w-60 that hasnt been available for decades
the bmw engine oil will prematurely wear out your syncho nizers - see below
my experience using it (2004) was notchy shifting - esp when cold, and that the gear shift lever would freeze and not go into the next gear at WOT (aborted shifts) esp betwen 1-2. When i drained the fluid it was full of bronze flecks. I put amsoil syncromesh back in it and that immediately restored function of my transmission like before. Ive never seen any bronze flecks in the trans fluid ive changed out since.
for what it matters my transmission is a blue tag zf6, with a remanufctured for GM plaque, on a 1993 corvette that i bougnt with 26k miles on it in 2001
ive been here 23 yrs and am not aware of any negative comments on amsoil syncromesh
if someone’s transmission doesnt work well with ansoil syncromesh, its got other issues
Last edited by dizwiz24; May 4, 2024 at 02:11 PM.
Race Director
Joined: Sep 2001
Posts: 14,680
Likes: 752
From: NEwhere Ohio
one such is that you should never use scotch-brite to clean an engine deck bc it releases abrasive aluminum oxide particles into the cylinder bores and then acts like he is a genius for recommending against an idea that everybody has done for years
any common sense mechanic doing head R&R work simply sucks out any cleaning fluid/abrasive particles from the cylinder bore, with a shop vac, before bolting the heads back on
Last edited by dizwiz24; May 4, 2024 at 11:24 AM.
Thread Starter
Racer
Joined: Jul 2022
Posts: 494
Likes: 162
From: Wilmington,Delaware
zfdoc’s advice is outdated and website un-updated from a time when the original 5w-30 based trans oil (note its not motor oil) was discontinued and modern syncromesh fluid wasnt yet available
some early users of bmw engine oil (10w-60) castrol had decent luck however most havent - esp recently. The guys who have had good luck i suspect are using some early version of castrol 10w-60 that hasnt been available for decades
the bmw engine oil will prematurely wear out your syncho nizers - see below
my experience using it (2004) was notchy shifting - esp when cold, and that the gear shift lever would freeze and not go into the next gear at WOT (aborted shifts) esp betwen 1-2. When i drained the fluid it was full of bronze flecks. I put amsoil syncromesh back in it and that immediately restored function of my transmission like before. Ive never seen any bronze flecks in the trans fluid ive changed out since.
for what it matters my transmission is a blue tag zf6, with a remanufctured for GM plaque, on a 1993 corvette that i bougnt with 26k miles on it in 2001
ive been here 23 yrs and am not aware of any negative comments on amsoil syncromesh
if someone’s transmission doesnt work well with ansoil syncromesh, its got other issues
some early users of bmw engine oil (10w-60) castrol had decent luck however most havent - esp recently. The guys who have had good luck i suspect are using some early version of castrol 10w-60 that hasnt been available for decades
the bmw engine oil will prematurely wear out your syncho nizers - see below
my experience using it (2004) was notchy shifting - esp when cold, and that the gear shift lever would freeze and not go into the next gear at WOT (aborted shifts) esp betwen 1-2. When i drained the fluid it was full of bronze flecks. I put amsoil syncromesh back in it and that immediately restored function of my transmission like before. Ive never seen any bronze flecks in the trans fluid ive changed out since.
for what it matters my transmission is a blue tag zf6, with a remanufctured for GM plaque, on a 1993 corvette that i bougnt with 26k miles on it in 2001
ive been here 23 yrs and am not aware of any negative comments on amsoil syncromesh
if someone’s transmission doesnt work well with ansoil syncromesh, its got other issues
