Hi,

I have a 2003 that I bought new and a 2000 that I bought used about a year later. The 2003 always shifted smoothly, but the 2000 felt different. It was always more difficult to shift. It acted like there was more friction while moving the lever. I adjusted and lubricated the linkage, but it was never like the 2003.

Recently it seemed to get worse, I was finding that at times I would be sitting at a light waiting for the green and when I let out the clutch, it would jump out of gear. It also did it in reverse. It happened more and more often. I thought maybe my clutch was not disengaging or something...

A co-worker was telling me he had the same issues with a late model GTO; he replaced the transmission oil with Royal Purple synthetic ATF and it made a huge difference.

I looked on the Corvette Forum and noticed the warnings about not using synthetic ATF on the 2000 and older transmissions.
However, I don't see anyone experiencing any actual damage from using this fluid.
I do hear damage going on in my trans, everytime it jumps out of gear and grinds.

I decided to replace the fluid.
Within one mile, the difference was unbelievable. It felt better than my 2003, immediately.

I highly recommend this to anyone that has a similar problem.

I will keep you members posted if my transmission fails from using this fluid. It shifts like silk now.
It has not jumped out of gear, one time since.

I would like to hear from anyone that actually has experienced problems.

Thanks,

Mike

 

I've heard just by changing it with the oem oil it makes a huge difference.

 

I'm having the exact same problems with my 2000 also. Hopefully this may resolve my issues as well. Thanks for the info!

 

I changed mine years ago and it's been fine ever since.
It also did wonders for my Harley, best mod I ever did to it!

 

You would have had the same result if you'd gone with fresh OEM fluid... Glad it's shifting smoother now though.

 

Sounds to me like the tranny fluid just needed changing and may not have mattered what you put back in (OEM vs. other), but glad it is working well with the Royal Purple. I'm sure its nice to have a smoothing shifting car again.

 

That's funny,
I posted this question and it looks like all but one that answered, have either a FRC or Z06.
My car was also an FRC.

 

i had exactly the same experience. mine shifts good now with RP. i wondered if the dexron would give the same result. i would point out that the manual says you never have to change the fluid. now we always trust the factory engineers who designed the car as we should but in this case i would question how this transmission can run forever on the same 4 quarts of dexron. obviously there is a problem shifting once you have some miles on the car. i have seen many posts regarding this.

 

If you are 2000 and older and using the Royal Purple. You need the Synchomax not the ATF. I have a 98 and was experiencing a vibration at high RPM. With RP it is smooth as silk.

 

big of a deal is it to change the fluid ?

 

Always do a shifter alignment procedure too as this can cause issues more than fluid changes.

 

Unless I'm mistaken, your question was that you wanted to hear from any who've had the life of their pre-2001 T56 transmission shortened by using synthetic fluid... And how exactly would you propose that one would determine that? Buy two C5's equipped with paper blocking rings and run one synthetic and one stock and then tear them both down at regular intervals to examine the blockers?

Putting synthetic in a trans with paper blockers won't kill it instantly; it will just shorten it's life. That's not coming from me; that's what tremec said when I called and asked about it when I had my last C5 (which was a 2000 and had paper blockers). They told me that I should not put synthetic fluid in my trans. Maybe I'm crazy, but I figure since they built the transmission why question them? It's no skin off their nose if you run synthetic, dex, or antifreeze in your gearbox. They don't have any motive to lie or embellish. In fact; they'd want to recommend that you use whatever will give your transmission the fewest problems and longest life to further strengthen their reputation as a quality gearbox builder...

Also, what do you have against the stock fluid? Is there some deficiency with it that I'm not aware of? Any time you swap your ~10 year old transmission fluid with fresh fluid (no matter what kind) your transmission will shift better...

There are MANY threads on this issue on this forum and I don't understand the debate. What exactly do people feel like they are losing by going with the stock fluid? There is no hard evidence that I'm aware of as to whether synthetic shortens the life of paper blockers but the transmission maker says it will; so why take the risk?

 

Easy. http://www.toquez06.com/tranny.html

 

You will damage the paper blocker rings over a long period of time. It took me 4 years to destroy mine. What an expensive mistake that was.

Get that fluid out of there! But then again your trans is probably already damaged in other areas from what you described.

 

Seems to be non-concurrent info floating around ... guess I wouldn't expect anything but that on the internet. What's true ... who knows?

See the first post in this link:
http://www.svtownersassociation.com/...ead.php?t=6295

----------------- Info from Link ----------------------

http://www.cnyfirebird.com/showArticles.asp?ID=15

"THE Word" on 1998-2002 Manual Tranny Lubricant
The question about whether one should run synthetic ATF or even a non-ATF gear lube in the f-body's Borg-Warner/Tremac 6-speed tranny has been bouncing around. Mark DeCarlo, co-organizer of CNYF, has tracked down the answer. Mark reports....

"I spoke with the T-56 expert at Tremec. He said that the Mobil 1 Synthetic ATF is an excellent choice for the T-56, PROVIDED that the T-56 is a 1997 model or newer.

DO NOT run the synthetic ATF in the pre-1997 T-56 units. It will destroy the paper on the blocker rings. And do not run it in a manual trans with brass blocker rings either, because it will ruin those also.

Tremec changed the blocker rings to the carbon fiber type for the 1997 model year and synthetic ATF will not degrade these."

 

The carbon fiber rings weren't put into Corvette T56 transmissions until the 2001 model year. 1997 - 2000 C5's have paper rings.

The story about synthetic destroying paper rings does seem to be consistent based on this post.

 

I agree. The BW transmissions had the paper blocker rings and '98 was supposed to be the last year of those. My '99 got a BW in it when it should have received a Tremec. My trying Mobil1 trans fluid, destroyed the BW within a month. I gave up and put in a Tremec with no more issue.

 

Like I said ... mucho non-concurrent info floating around on this subject. The other link info is talking about F-body T56 transmissions, which is just an engine mounted version of the T56. Why would Tremec wait 3 years to change the Corvette T56 to carbon fiber rings when they already supposedly did it to the other T56 variants?

 

No idea and I didn't know that about the F-bodies but the statement about the paper blockers in 97-00 C5's is not a guess. I have personally seen a 2000 C5 trans torn down and it had paper blockers in it. I've also spoken to a tech who has worked on quite a few C5 transmissions and he said that only the 01+ C5's had carbon rings...

 

OK ... I just got off the phone with Tremec Tech Dept (talked to Rob). Tired of non-concurring info on this.

Tremec Tech Dept said:

1) ALL GM vehicles with at T-56 transmission started using the carbon blocker rings in the 2002 model year. He said GM had to approve the design, and therefore the 2002 model year is when the carbon rings made it into production for ALL GM vehicles. So, the info in the link I references saying F-body T-56s started using carbon blocker rings in 1998 is false.

2) He said that Tremec has tested various synthetic transmission oils for compatibility with the T-56. He said that Mobil 1 Full Synthetic AFT IS recommend even for the T-56 transmissions with the paper blocker rings. They DO NOT recommend Royal Purple or Redlline because of additives that they use that are not in Mobil 1. He didn't give me a whole list of non-approved fluids, only the RP and RL ... there could be others. But bottom line is Tremec says Mobil 1 ATF has been tested to be comparable with the paper blockers.

This is info directly from the Tremec Tech Dept ... don't shoot the messenger.

PS - cdkcorvette7, looks like there's still a slight discrepancy on if the carbon rings started with 2001 or 2002 model year Vettes ... but I was just told that ALL GM vehicles with T-56 transmissions started using the carbon rings in the 2002 model year.