MN6 Transmission Fluid
Thread Starter
Melting Slicks
Joined: Jun 2013
Posts: 3,473
Likes: 691
From: West Virginia
MN6 Transmission Fluid
So, for years now, I have been running Mobil 1 Dex III synthetic in my MN6 - I have a stash of it I bought years back, same stuff I use in my Chev K1500 transfer box. Lately however, I have seen some odd issues - very easy and smooth shifting when cold, but liable to the occasional grind or "balk" when hot. Especially balky going for 1st to 2nd (seemed like it did not want to go all the way home, like the locking rings just stopped it fully engaging) and a very occasional grind going from 5 to 6. Plus "iffy" getting into 1st from a standstill.
I decided that maybe the oil was just too slippery, and the synchronizers were maybe not able to get the job done when the tranny was hot.
So, this week I dumped the Mobil 1 and filled with Valvoline DexIII/Merc, non synthetic. Took it out for a long run today, and night and day difference. No issues at all, slips easily into 1st, almost buttery shifts, except when very cold - temps here are down around freezing, and the car is in a detached garage.
So maybe the Tremec guys were on the money after all when they said, nothing fancy needed, just use plain old Dex III.
I decided that maybe the oil was just too slippery, and the synchronizers were maybe not able to get the job done when the tranny was hot.
So, this week I dumped the Mobil 1 and filled with Valvoline DexIII/Merc, non synthetic. Took it out for a long run today, and night and day difference. No issues at all, slips easily into 1st, almost buttery shifts, except when very cold - temps here are down around freezing, and the car is in a detached garage.
So maybe the Tremec guys were on the money after all when they said, nothing fancy needed, just use plain old Dex III.
Last edited by jackthelad; Dec 5, 2014 at 03:46 PM.
Safety Car
Joined: Jan 2006
Posts: 3,940
Likes: 43
From: shavertown Pa.
I talked to a guy here that raced ricers he told me that most of the 6 speed honda problems were linked to folks thinking they would do the transmission a favor and use synthetic.
I stayed away from the 6 speeds because of the problems he said the synthetic fluid was too slippery and caused these problems.
A few years ago I owned a z06 that I changed to mobil 1, it had the same grind going into second, now maybe I think I caused the problem.
I stayed away from the 6 speeds because of the problems he said the synthetic fluid was too slippery and caused these problems.
A few years ago I owned a z06 that I changed to mobil 1, it had the same grind going into second, now maybe I think I caused the problem.
Drifting
Joined: Sep 2009
Posts: 1,719
Likes: 4
From: cinnaminson n.j.
St. Jude Donor '14
What year is your car? There have been a lot of posts advising not using synthetic fluid in the early t56's due to the "paper" synchronizers. Rick Kim at rkt56 advised me to use the gm synchromesh fluid in my 2000. This is what GM has listed.
2000 Chevrolet Corvette V8-5.7L VIN G
Vehicle » Transmission and Drivetrain » Manual Transmission/Transaxle » Fluid - M/T » Specifications » Fluid Type Specifications
FLUID TYPE SPECIFICATIONS
Transmission Fluid Manual Transmission and Transfer Case Fluid P/N 88861800
2000 Chevrolet Corvette V8-5.7L VIN G
Vehicle » Transmission and Drivetrain » Manual Transmission/Transaxle » Fluid - M/T » Specifications » Fluid Type Specifications
FLUID TYPE SPECIFICATIONS
Transmission Fluid Manual Transmission and Transfer Case Fluid P/N 88861800
