Manual Trans Fluid
Thread Starter
Instructor
Joined: Sep 2007
Posts: 168
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Just an FYI for the discussion, here is what the 2008 manual says for the manual trans fluid:
"Manual Transmission Fluid (GM Part No. U.S. 88861800, in Canada 88861801)"
No other specification is noted. For the auto trans it says:
"DEXRON®-VI Automatic Transmission Fluid"
"Manual Transmission Fluid (GM Part No. U.S. 88861800, in Canada 88861801)"
No other specification is noted. For the auto trans it says:
"DEXRON®-VI Automatic Transmission Fluid"
Racer
Joined: Nov 2002
Posts: 386
Likes: 10
The warranty issue is a non issue. If you crawled under to the car to put in RP in the first place you can crawl under the car again to change back to GM approved fluid before you take it in for repairs.
My 06 C6 shifting improved greatly when I installed RP Sychromax. Apparently my 08 Z06 doesn't require any as they either improved the transmission, the fluid or the shifter greatly or all incrementally. This transmission shifts really smoothly even when ice cold.
My 06 C6 shifting improved greatly when I installed RP Sychromax. Apparently my 08 Z06 doesn't require any as they either improved the transmission, the fluid or the shifter greatly or all incrementally. This transmission shifts really smoothly even when ice cold.
I also put RP Synchromax in my 06 C6. Shifting became slightly smoother, but the rear-mounted T56 and the longer linkage associated with it is still pretty clunky.
Drifting
Joined: Jun 2005
Posts: 1,837
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I also found a GM document referencing P/N 88861800 as "manual transmission fluid" and saying that Dexron III can be used if its not available, but not to use Dexron VI in any manual transmissions or transfer cases.
Possibly P/N 88861800 is just the new Dexron III, mainly due to branding issues and not wanting to have too many "Dexrons" floating around confuseling people.
Le Mans Master
Joined: Jan 2005
Posts: 5,611
Likes: 5
From: Thousand Oaks California
Also, Dexron VI ATF should not to used in the Tremec T56.
So, back in 2005, it was Dexron III, spec H, but today it is Manual Transmission Fluid GM P/N 88861800 (Canadian P/N 88861801) for the Tremec 6 speed. I believe GM P/N 88861800 is the same as what Dexron III, spec H was back in 2005.
Last edited by calemasters; Dec 11, 2007 at 04:34 PM.
Safety Car
Joined: Apr 2006
Posts: 4,254
Likes: 5
From: Anaheim Hills, Ca
When the fluid is cold, it viscous; thicker. The problem is when the syncros engage, they don't get up to speed fast enough to sync to the next gear due to the thickness of the fluid. Either double clutch or hold the shifter in the syncro notch longer, then slide it the rest of the way.
Personally, I double clutch until the tranny warms up.
Personally, I double clutch until the tranny warms up.
Thread Starter
Instructor
Joined: Sep 2007
Posts: 168
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When the fluid is cold, it viscous; thicker. The problem is when the syncros engage, they don't get up to speed fast enough to sync to the next gear due to the thickness of the fluid. Either double clutch or hold the shifter in the syncro notch longer, then slide it the rest of the way.
Personally, I double clutch until the tranny warms up.
Personally, I double clutch until the tranny warms up.
I have been double clutching it. . .
My thought of going to synthetic is that they are more "fluid" when cold than non synthetic, as noted in my old snow car in which I tested the difference in motor oil.
Regular oil (5W30) 8 degrees F cold start in the morning (first one of the day): Valve tap for about 20 seconds.
Changed the oil (and filter) that day to Mobil 1 Synthetic 5W30
Next morning, also 8 degrees: Valve tap for less than 1 second.
That sold me on Mobil 1 and now all our cars have it.
I thought perhaps the same would be true in trans fluid when it comes to the synchros. While they are both (non synthetic vs synthetic) more viscous, the synthetic would flow better and improve cold shifting by allowing the synchros to do their job faster.
Safety Car
Joined: Apr 2006
Posts: 4,254
Likes: 5
From: Anaheim Hills, Ca
So, you noticed this too? Good, it's not just me then and hopefully for both us it's not a problem, but the nature of the beast.
I have been double clutching it. . .
My thought of going to synthetic is that they are more "fluid" when cold than non synthetic, as noted in my old snow car in which I tested the difference in motor oil.
Regular oil (5W30) 8 degrees F cold start in the morning (first one of the day): Valve tap for about 20 seconds.
Changed the oil (and filter) that day to Mobil 1 Synthetic 5W30
Next morning, also 8 degrees: Valve tap for less than 1 second.
That sold me on Mobil 1 and now all our cars have it.
I thought perhaps the same would be true in trans fluid when it comes to the synchros. While they are both (non synthetic vs synthetic) more viscous, the synthetic would flow better and improve cold shifting by allowing the synchros to do their job faster.
I have been double clutching it. . .
My thought of going to synthetic is that they are more "fluid" when cold than non synthetic, as noted in my old snow car in which I tested the difference in motor oil.
Regular oil (5W30) 8 degrees F cold start in the morning (first one of the day): Valve tap for about 20 seconds.
Changed the oil (and filter) that day to Mobil 1 Synthetic 5W30
Next morning, also 8 degrees: Valve tap for less than 1 second.
That sold me on Mobil 1 and now all our cars have it.
I thought perhaps the same would be true in trans fluid when it comes to the synchros. While they are both (non synthetic vs synthetic) more viscous, the synthetic would flow better and improve cold shifting by allowing the synchros to do their job faster.
Melting Slicks
Joined: Feb 2006
Posts: 3,271
Likes: 182
From: Manassas VA
Yeah but you can't get all of it out and when they see the fluid has some purple tint to it then you're in for it
I also put RP Synchromax in my 06 C6. Shifting became slightly smoother, but the rear-mounted T56 and the longer linkage associated with it is still pretty clunky.
I also put RP Synchromax in my 06 C6. Shifting became slightly smoother, but the rear-mounted T56 and the longer linkage associated with it is still pretty clunky.
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Tech Contributor
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St. Jude Donor '08-'09-'10-'11
When I went to get some to refill what I lost during the clutch swap removing the driveline...The manual said Dex 3 so I went and the tech looked it up. The computer said Dex 3 had been replaced and to see Dex 4. When he looked up dex 4 it said see dex 6. I used dex 6 until upgrading my MZ6 for a level 4 unit. I dont know what Cartek filled it with.
Thread Starter
Instructor
Joined: Sep 2007
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Here is the 88861800 bottle (front and back, I just picked one up this morning):
LINK
I am having it analyzed by Royal Purple (they volunteered) and I'll let you know what they find.
Anyone know what the GM specification 9986252 is?
LINK
I am having it analyzed by Royal Purple (they volunteered) and I'll let you know what they find.
Anyone know what the GM specification 9986252 is?
Last edited by vcrz; Dec 13, 2007 at 02:21 PM.
Thread Starter
Instructor
Joined: Sep 2007
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I had the 88861800 fluid analyzed by Royal Purple and they found that it has almost the exact characteristics of Dexron III and that Max ATF or Synchromax will be great replacements, but Synchromax is their first recommendation.
Racer
Joined: Oct 2007
Posts: 392
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From: Smyrna Delawere
Has anyone replaced their manual trans fluid with something other than the stock Dexron fluid?
If so, have you notice a significant improvement in cold shifts, like when it is around 30 to 40 degrees outside for the first few shifts?
Mine is very notchy in those temps when cold going into second and third; but when warmed up (within a few minutes) it shifts very smoothly. So I was wondering if something like Redline's MTL would help with the cold shifts.
If so, have you notice a significant improvement in cold shifts, like when it is around 30 to 40 degrees outside for the first few shifts?
Mine is very notchy in those temps when cold going into second and third; but when warmed up (within a few minutes) it shifts very smoothly. So I was wondering if something like Redline's MTL would help with the cold shifts.
Intermediate
Joined: Oct 2005
Posts: 32
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I switched to Mobil 1 synthetic ATF in my 05 MN6 at the beginning of the summer and firmly believe that the shifting is even more notchy than with the factory fluid. I notice this when the car is hot or cold. I have 4 quarts of synchomax sitting on my work bench next to my car under its winter cover.
Safety Car
Joined: Sep 2000
Posts: 3,604
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From: Austin, TX
Premium Supporting Vendor
Joined: Aug 2001
Posts: 5,364
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From: King George VA
Been using AMSOIL ATF, a fluid suitable for Dexron III specifications in my 02 Z06 for years and in my 06 CTS-V since last year. Works well in both.
Another suggestion that I may try in my Z06 this season is the AMSOIL Torque-Drive Synthetic Transmission Fluid. This is also a Dexron III fluid, but has a little higher viscosity than the AMSOIL ATF and I feel it may work a little better on the track.
Another suggestion that I may try in my Z06 this season is the AMSOIL Torque-Drive Synthetic Transmission Fluid. This is also a Dexron III fluid, but has a little higher viscosity than the AMSOIL ATF and I feel it may work a little better on the track.
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