Help! Transmission problems

[DagWide]

Hi! Sweden calling!
I have been driving Corvettes for many years. Now I have a Z06, 2006, 15000 miles. I love the car but I must say I’m not fond of this transmission at all. They use a modified T-56 transmission in the Z06. This transmission is found in many other cars like the Aston Martin DB9, so it should be a well tested transmission. I recall having read that the transmission was changed or modified in 2008. Does anybody know?
My problems: First of all, there is a lot of noise from the transmission below 1500 rpm. I have read that that this is “normal” but I can’t say I‘ve heard similar sound from the gearbox in any other car. Can anybody explain why I have this noise and if it’s like this in all Corvettes with manual transmission, even newer Corvettes? Secondly, I have to use some force to put the car into gear especially into first and the reveres gear. Even if it’s a “racing transmission” I expected a “smoother” gear change!

 

[c4c5specialist]

HI there,

#1, the Vanquish or Vanquish S were the only 2 Astons equipped with the T56.
DB9 had an italian based six speed manual made by Graziano.

As for the noise, because you have a torque tube that spins at all times where most others do NOT.

#2, you might try to get your shifter adjusted to assist in the function of the gear selection. The transmission was redesigned in 2005 for the c6 and works very well. Revised syncronizers and different shift rails and better shifter were all updates.

Corvette is its own design and cannot be truthfully compared to any other car because none other has the backbone torque tube design.

Allthebest, c4c5

 

[Hib Halverson]

In re: the high shift effort...another thing you might check is your clutch hydraulics. If there's any air in the system, you may have a problem with not getting a full clutch release when shifting.

As for the transmission noise, what kind of noise do you hear?

Whine?
Howl?
Grind?
Growl?
Click?

What...?

 

[DagWide]

In re: the high shift effort...another thing you might check is your clutch hydraulics. If there's any air in the system, you may have a problem with not getting a full clutch release when shifting.

As for the transmission noise, what kind of noise do you hear?

Whine?
Howl?
Grind?
Growl?
Click?

What...?

Hi! I will check the clutch hydraulics! It's more like a rattle. It might be the spinning torque tube but I think it's rather annoying! Thank you! Best regards Dag

 

[DagWide]

HI there,

#1, the Vanquish or Vanquish S were the only 2 Astons equipped with the T56.
DB9 had an italian based six speed manual made by Graziano.

As for the noise, because you have a torque tube that spins at all times where most others do NOT.

#2, you might try to get your shifter adjusted to assist in the function of the gear selection. The transmission was redesigned in 2005 for the c6 and works very well. Revised syncronizers and different shift rails and better shifter were all updates.

Corvette is its own design and cannot be truthfully compared to any other car because none other has the backbone torque tube design.

Allthebest, c4c5

Hi and thank you for your answer! I guess you are right about the Astons and T56! But why the spinning torque tube? There must be some sort of advantage!
The shift problem: It's diffucult to explain the feeling but it is a "numb" feeling in the shifterputting in to first and reverse gear. Not always but often it's a resistance getting the car in to second gear. Do you think it's the shifter or can it be, what Hib halverson suggested; air in the clutch hydraulics?
Best regards, Dag

 

[JThomas]

I have an '07 Z06 that was built in October of 2006. In May of this year, I was having great difficulty getting the car into reverse. Took it to the dealer and they found a problem with the reverse sychros and some wear on the fifth and sixth gears. They also inspected the rear end, because I had an intermittent "whine" at freeway speeds and there was an issue with the rear end.

I have owned the car since new and had accepted some transmission "noise" as normal for the car, because I had not driven any other Z06.

After my car was repaired, I have none of the aforementioned "noises" I had come to associate with my car. It now shifts smoother than before with no whine, noise, etc.

All done under warranty and to my satisfaction. The car now has just over 30,000 miles. The repairs were done at 25,000 miles.