[Mgorski]

Don't know if someone started one, but I need reasons why my 6spd auto is better (in my mind) than the 8spd. All I can come up with is, since I'm lazy I don't have to shift as often. Is the 6 speed cooler? Classic? Or just worthless slow and heavy.
I guess I don't have any problems with it, it's just knowing about the 8.
Or is the 8 only offered in the z06?

 

[Redc7]

Sorry everything I read the 8-speed is better and will be on the 2015 Stingrays. Only thing I can say is the 6-speed has been around awhile the 8-speed is new.

 

[Mgorski]

Sorry everything I read the 8-speed is better and will be on the 2015 Stingrays. Only thing I can say is the 6-speed has been around awhile the 8-speed is new.

Ya that's true. More moving parts! Not by much tho. I'll just have to embrace it. And say mine will b more rare lol

 

[rdslon01]

The six speed may be more durable (but only time will tell). It has been refined over the years and is known to be high quality with no glitches. There may be some growing pains with the eight speed. I am sure GM will get there with the eight speed (if it turns out that the eight speed has some initial glitches), and, in the meantime, that GM will take care of people with the warranty. However, your six speed is proven while the eight speed - well, you know how first model years can have some glitches which must be worked.

 

[jsvette]

For me in purchasing and enjoying cars, I do it with the mindset that there will always be something new, different, more powerful or whatever just around the proverbial corner so to speak. If you delay your purchase and wait for the next thing how exactly do you know that you waited for the right time to take the jump? I purchased RedHot eyes-wide-open 'cause it had spectacular design and amazing power. I wasn't disappointed and in fact found it including the automatic to exceed expectations on all levels. The fact that they will be offering the 8 speed doesn't take away from the tremendous fun and pleasure I am getting from RedHot right now and in no way diminishes my purchase. I suggest you don't look to someone else to explain why the 8 may or maynot be better than the 6, rather get out and drive yours, use the paddle shifters, set it to sport and enjoy the heck out of it without any regrets.

 

[CruznCorvette]

Just like the 6 spd was better than the 4 spd, I'm sure the 8 spd will be better and can handle more torque than the 6 spd.

General Motors shall introduce a new rear wheel drive eight speed automatic transmission, known as the 8L90, in the 2015 Chevrolet Corvette. The rated turbine torque capacity is 1000 Nm. This transmission replaces the venerable 6L80 six speed automatic transmission. The objectives behind creation of this transmission are improved fuel economy, performance, and NVH. Packaging in the existing vehicle architecture and high mileage dependability are the givens. The architecture is required to offer low cost for a rear drive eight speed transmission while meeting the givens and objectives. An eight speed powerflow, invented by General Motors, was selected. This powerflow yields a 7.0 overall ratio spread, enabling improved launch capability because of a deeper first gear ratio and better fuel economy due to lower top gear N/V capability, relative to the 6L80. The eight speed ratios are generated using four simple planetary gearsets, two brake clutches and three rotating clutches. The resultant on-axis transmission architecture utilizes a squashed torque converter, an off-axis pump and four close coupled gearsets. The three rotating clutches have been located forward of the gearsets to minimize the length of oil feeds which provides for enhanced shift response and simplicity of turbine shaft manufacturing.

The transmission architecture features a case with integral bell housing for enhanced powertrain stiffness. A unique pump drive design allows for off-axis packaging very low in the transmission. The pump is a binary vane type which effectively allows for two pumps in the packaging size of one. This design and packaging strategy not only enables low parasitic losses and optimum priming capability but also provides for ideal oil routing to the controls system, with the pump located in the valve body itself.

The transmission controller is externally mounted, enabling packaging and powertrain integration flexibilities. The controller makes use of three speed sensors which provide for enhanced shift response and accuracy. Utilization of aluminum and magnesium components throughout the transmission yields competitive mass. The dedicated compensator feed circuit, used in GM six speed designs, was supplanted by a lube-fed design in order to simplify oil routing and enhance shift response. Packaging is within that of the GM 6L80 design, allowing for ease of application integration.

The overall result is a robust, compact, and cost effective transmission which offers significant fuel economy and performance benefit, over its six speed counterpart, and shall provide an attractive balance of overall metrics in the automatic transmission market.

 

[rdslon01]

What was your source for this information?

Is it a fact that all 2015 Corvettes will get the eight speed, or is it still up in the air? What if the 2015 StingRays will continue to get the six speed, and only the Z06 will get the eight speed for 2015? Then the StingRays may pick up the eight speed for 2016. One reason I am saying this might be a possibility that no one has seemed to mention yet is are we sure how ready the eight speed is? For the 2015 StingRay, it has to be ready by June or July. For the 2015 Z06, it does not have to be ready until December.

Does anyone know for sure? Mr. John Elegant, did you get such information at the NAIAS in Detroit?

 

[mjw930]

What was your source for this information?

Is it a fact that all 2015 Corvettes will get the eight speed, or is it still up in the air? What if the 2015 StingRays will continue to get the six speed, and only the Z06 will get the eight speed for 2015? Then the StingRays may pick up the eight speed for 2016. One reason I am saying this might be a possibility that no one has seemed to mention yet is are we sure how ready the eight speed is? For the 2015 StingRay, it has to be ready by June or July. For the 2015 Z06, it does not have to be ready until December.

Does anyone know for sure? Mr. John Elegant, did you get such information at the NAIAS in Detroit?

Here's a link to the redacted SAE document that states quite clearly this is intended for the 2015 C7 but we don't know if it's just the Z06.

http://www.thetruthaboutcars.com/20...ettes-8-speed-auto-gets-redacted/#more-676170

Personally, I think it's all 2015's. The expense to have 3 transmissions in the mix outweighs the issues of production and I don't see production as a problem. They have until August to get them in full production and GM is one of the worlds largest transmission manufacturers.


Sent from my iPad using Corvette Stingray Forum

 

[mjw930]

Here's an article on the 8 speed production, it's dated June 12th, 2013. Looks like they will be in production of the trans within weeks (1st quarter 2014).

http://www.13abc.com/story/18769971/toledo-gm-plant-readies-for-new-8-speed-transmission

There is really no excuse to not have available for all 2015 C7's.



Sent from my iPad using Corvette Stingray Forum

 

[rdslon01]

Yelp, that 13abc.com article is very convincing. I think you are correct. They should be ready for full production before the 2015 StingRay builds start up in June or July.

Great find!

 

[Dusty Starbucks]

Ya that's true. More moving parts! Not by much tho. I'll just have to embrace it. And say mine will b more rare lol

Haha! That's funny, last month I sold a 4 speed transmission out of a 66' Mustang GT for $2K... you could be on to something

 

[Mgorski]

For me in purchasing and enjoying cars, I do it with the mindset that there will always be something new, different, more powerful or whatever just around the proverbial corner so to speak. If you delay your purchase and wait for the next thing how exactly do you know that you waited for the right time to take the jump? I purchased RedHot eyes-wide-open 'cause it had spectacular design and amazing power. I wasn't disappointed and in fact found it including the automatic to exceed expectations on all levels. The fact that they will be offering the 8 speed doesn't take away from the tremendous fun and pleasure I am getting from RedHot right now and in no way diminishes my purchase. I suggest you don't look to someone else to explain why the 8 may or maynot be better than the 6, rather get out and drive yours, use the paddle shifters, set it to sport and enjoy the heck out of it without any regrets.

Thank you! Very inspiring, you're right. I am never unsatisfied whenever I take it for a drive. Even if it's just to pick up dry cleaning.