LFZ

me too.

Rusc6z06

I wonder if the 1-2nd problem has anything to do with 1-4th mode?

jmalto

Not sure but I have a CAGS fuse to overwrite the skip shift.

LFZ

I just checked my clutch fluid...its dark and dirty....looks like I'll be flushing this weekend.

Z06 RB

Exactly.

jmalto

I started changing mine every week, my wife thinks I am nuts

Painrace

160 degrees water temperature is not the same as 160 degrees oil temperature. I suggest you get the engine oil temperature up to 130-140 degrees and he transmission should shift fine.

Jim

Jasil

^^^^^^^^
I agree and there is no way to tell how warm the transmission fluid is. My point was after a good period parked water was still warm. My whole reason for the post was something changed never had a problem before driving this same trek of road, same warm up procedures, if anything ambient is hotter now than ever, so trans and everything else should warm up faster. This time there was grinding!!

2 flushes later no grinding...........drove her again this morning.......after getting supremely pissed about the "Cash for Clunkers" program and watching a fox body, lighning, L98 get trashed and again no grinding, so far so good :-)

King Tut

I figured I would bring this thread back up. I purchased my 2009 last month, and I have been having 1st to 2nd gear grind issues since I got it. Once the engine oil is up to temp on the temp gauge, the grinding goes away so I assume the transmisison fluid is up to temp. I also cringe every time I have to shift to second. I normally try and short shift into second and let the revs fall all the way to help the issue, but that is very annoying. I don't understand how flushing your clutch fluid will prevent grinding that occurs within the transmission. My clutch works just fine. It is the synchros in the transmission and the transmission oil that are causing the grinding. Should I just live with this and hope it gets better with miles (I have 1,800 miles currently) or should I take a chance and let a dealer look at it. I want to just assume this is inherent to the transmission, and I should live with it.

mirage2991

With the trans in the back, engine oil temp, or engine temps do not mean much. If it's really cold out, it will take for ever to get the trans fluid warmed up (since it has a trans cooler, I can only imagine! just see how long your engine oil takes to heat up to 160 on a 30 degree day...and we're talking oil in contact with HOT parts, not just soaking up friction heat as in the case of the trans).
I'd wager to say once it gets warm out again, there will be alot less complaints about it.

obzidian

Please be aware that it may NOT be your transmission at all that is causing most of your issues. Of course you should let the trans/engine warm up to operating temp before you start ripping on it and those folks in colder climates will have to wait a bit more than me, for example, in miami!

Nut, please be advised that there is a pressure plate TSB that is supposed to fix some issues found with these 08-09 cars. Good luck!

jumbojet

Good reading. I'm doing as much DD as possible before I take the plunge on a Z and determine what year is best for me.

Anyway. It seems like it would have been a good idea if GM installed some type of heating coil in the trans. Start the car and turn on the trans fluid heater(ALA defroster), and than it automatically shuts off after a minute or two. Once moving, the fluid is at temp. and everything works the same.

Just a thought.

LEE427

My brand new Z tranny also grinds.

Hey Jasil, I remember you from the Evo forums. Remember our Evo X's tranny grinded like a **** to..

hoserack

I have an 08 and flush it once in a while.
Mine is notchy and grinds 1-2 sometimes.
I say phuc it, if it breaks I'll deal with it.

But then again I was red lineing the car with 11 miles on it.

16k with only minor problems'

I also red line it with cold oil.

Me bad

ragtopws6

Here is a bulletin that was released by GM.

#PIP4357: Noise During The 1-2 Shift When Cold - keywords first grate grind second - (Feb 27, 2008)


Subject: Noise During The 1-2 Shift When Cold


Models: 2009 Cadillac CTS-V - Tremec Transmission

Equipped With Tremec Manual Transmission RPO Code MG9

2008-2009 Chevrolet Corvette, Corvette Z06

Equipped With Tremec Manual Transmission RPO Code MM6, MZ6 or MH3

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:
Some customers may comment about a Nibble or grate type noise that may also be described as a multiple bump feel during a 1-2 upshift event while the transmission is cold.

Recommendation/Instructions:
A new transmission synchronizer design was released for the 2008 and 2009 models listed above. The new synchronizer will make a noise when shifting from 1st to 2nd gear in temperatures at or below 32 degrees F.

This noise/feel is a normal characteristic and will go away after the transmission warms up. Warm up should occur after approximately 15 miles of normal driving. This condition requires no repair by the dealer.

The service technician should test drive the vehicle to verify the concern. If the noise/feel goes away after warm up no repair is necessary and the customer should be advised accordingly.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

I have repaired few TR6060's but they were repaired due to missing 2nd gear and not because of the grinding issue. The TR6060's have sintered bronze blockers that are more "grabby" compared to the compressed carbon blockers that are in T56's. When the fluid temp is cold, they don't "slide" all that well, meaning they grab or engage very quickly. The blocking rings job is to speed up or speed down the engaging gear to "synchronize" the slider and gear for engagement. When the bronze blockers grab, rather than slip, this defeats the purpose of smooth engagement.

Also, when Tremec designed the TR6060, they made the gears much more robust to handle more power. But in doing so, they had to make the sliders smaller to fit in the same space.









Sintered bronze blocking rings. They are not as smooth as carbon fiber blockers from T56 IMHO.





This is from a 2010 Camaro with 1,200 miles. Guess what happened? Owner was racing and missed 2nd.

King Tut

Well that makes me feel better. It definitely happens above 32 degrees F though. I will just be careful when shifting to 2nd until the car is warm. I have found that if I shift from 1st to 2nd at around 2000 RPM or lower I don't get the grind. Either that or keep the clutch in till the revs drop under 2000 RPM and then shift into 2nd.

C66 Racing

Ragtop - those are great pics - thanks for sharing!

ragtopws6

Hey Brad, it's been a long time. I'm working on a hybrid T56 for road racing crowd. Using 06-07 Z06 T56 parts (using the machenical pump) and ZR1 case (has the fitting for squirting directly at the 4th gear) it will be be a very nice set up. I'll post a thread on the build in couple of months.

MTIRC6Z

I've never driven a stock TR6060 trans, but I can tell you the my RPM L-5 modified TR6060 shifts WAY better than my stock T56 trans ever did.

I really don't think there's anything inherently wrong with the TR6060, it just needs to be properly put togther

Thus if you have reason to pull the trans it might be worth the extra time, effort and expense to get it replaced with a RPM built/modified version. For sure if you do this, you'll never have to do the job again.

Cheers, Paul.

PatriotZ

Ragtop....thanks, excellent post