8L90 in the 2015 Chevrolet Corvette !!! - CorvetteForum - Chevrolet Corvette Forum Discussion



C7 General Discussion
General C7 Corvette Discussion not covered in Tech
Sponsored by:
Sponsored by:

8L90 in the 2015 Chevrolet Corvette !!!

Reply
 
 
 
Thread Tools Search this Thread
Old 12-06-2013, 11:39 PM   #1
Runge_Kutta
CF Senior Member
Thread Starter
 
Member Since: Feb 2000
Location: East Bay CA
Posts: 1,195
Thanks: 0
Thanked 0 Times in 0 Posts
Default 8L90 in the 2015 Chevrolet Corvette !!!

1000 Nm = 737 lbf/ft


General Motors Rear Wheel Drive Eight Speed Automatic Transmission
Technical Paper
2014-04-01
James Michael Hart, Tejinder Singh, William Goodrich

General Motors Rear Wheel Drive Eight Speed Automatic Transmission 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.
Runge_Kutta is offline   Reply With Quote
Old 12-06-2013, 11:41 PM   #2
BeaZt
CF Senior Member
St. Jude Donor '14
 
Member Since: Jan 2008
Posts: 9,435
Thanks: 0
Thanked 0 Times in 0 Posts
Default

Is the date of that article correct April 1st?
BeaZt is offline   Reply With Quote
Old 12-06-2013, 11:45 PM   #3
Runge_Kutta
CF Senior Member
Thread Starter
 
Member Since: Feb 2000
Location: East Bay CA
Posts: 1,195
Thanks: 0
Thanked 0 Times in 0 Posts
Default

Runge_Kutta is offline   Reply With Quote
Old 12-06-2013, 11:46 PM   #4
themonk
CF Senior Member
St. Jude Donor '09, '12-'13-'14-'15-'16
 
themonk's Avatar
 
Member Since: Jul 2006
Location: Calgary, AB. There's a reason why white was the only color offered on every year Corvette. Proud Canadian German Jamaican!
Posts: 66,883
Thanked 420 Times in 255 Posts
Default

Quote:
Originally Posted by 1320vetteran View Post
Is the date of that article correct April 1st?
Marty, we got to get you back, to the future......published in 2014 huh.
themonk is offline   Reply With Quote
Old 12-06-2013, 11:50 PM   #5
kozmic
CF Senior Member
Support Corvetteforum!
 
kozmic's Avatar
 
Member Since: Jan 2013
Location: Houston TX
Posts: 533
Thanks: 0
Thanked 5 Times in 3 Posts
Default

While the date above does seem suspect, here is an article back from 7-12-2012 that also talks about a new 8-speed auto from GM being ready for full production sometime in the first quarter of 2014: http://www.13abc.com/story/18769971/...d-transmission

Last edited by kozmic; 12-06-2013 at 11:53 PM.
kozmic is offline   Reply With Quote
Old 12-06-2013, 11:53 PM   #6
rcallen484
CF Senior Member
Support Corvetteforum!
 
rcallen484's Avatar
 
Member Since: Dec 2011
Posts: 10,355
Thanks: 0
Thanked 1 Time in 1 Post
Default

Quote:
Originally Posted by 1320vetteran View Post
Is the date of that article correct April 1st?
Not sure how the date is interpreted but that link is definitely legit.

http://papers.sae.org/2014-01-1721/
rcallen484 is offline   Reply With Quote
Old 12-06-2013, 11:57 PM   #7
millpond
CF Senior Member
 
millpond's Avatar
 
Member Since: Aug 2005
Location: Bend OR
Posts: 2,573
Thanked 129 Times in 101 Posts
Default

Nice find! Will wait for model year 2015 since I will be going with the auto.

This is the abstract. The article has not been published yet.
To be published 4/1/2014 and presented at SAE congress 4/8/2014. The specs for this unit means it could also be used for the C7 Z06!

Last edited by millpond; 12-07-2013 at 12:50 AM.
millpond is offline   Reply With Quote
Old 12-07-2013, 12:06 AM   #8
BeaZt
CF Senior Member
St. Jude Donor '14
 
Member Since: Jan 2008
Posts: 9,435
Thanks: 0
Thanked 0 Times in 0 Posts
Default

Quote:
Originally Posted by rcallen484 View Post
Not sure how the date is interpreted but that link is definitely legit.

http://papers.sae.org/2014-01-1721/
True. The date sent me for a loop.
BeaZt is offline   Reply With Quote
Old 12-07-2013, 12:06 AM   #9
SpryGeezer
CF Senior Member
 
SpryGeezer's Avatar
 
Member Since: Apr 2007
Location: ABQ NM
Posts: 1,468
Thanked 1 Time in 1 Post
Default

SpryGeezer is offline   Reply With Quote
Old 12-07-2013, 04:57 AM   #10
musclecar6
CF Senior Member
 
Member Since: Oct 2004
Location: matthews nc
Posts: 8,539
Thanked 46 Times in 36 Posts
Default

Well well well. Very interesting paper. If accurate, and it seems to address exactly the modern auto/DCT issues many of us have been talking about, we could be on the verge of deja vu all over again. Back to the future with a 2014/2015 repeat of the 2005/2006 C6 auto tranny transition. Suurprise, Suurprise !!!!
musclecar6 is offline   Reply With Quote
Old 12-07-2013, 06:53 AM   #11
peter pan
Life Time NCM #2196
Support Corvetteforum!
 
peter pan's Avatar
 
Member Since: Sep 2004
Location: Converse TX
Posts: 75,500
Thanked 11 Times in 11 Posts
Default

Awesome looking forward to the new A8 tranny
peter pan is offline   Reply With Quote
Old 12-07-2013, 07:17 AM   #12
JerriVette
CF Senior Member
 
JerriVette's Avatar
 
Member Since: Nov 2003
Location: Bergen county NJ
Posts: 7,886
Thanked 212 Times in 175 Posts
Default

Cool!
JerriVette is offline   Reply With Quote
Old 12-07-2013, 08:39 AM   #13
Shrike6
CF Senior Member
Support Corvetteforum!
Cruise-In 7, 9 & 12 Veteran
Wounded Warrior Escort '11
St. Jude Donor '07-'08-'09-'10-'11
 
Shrike6's Avatar
 
Member Since: Mar 2005
Posts: 9,714
Thanks: 0
Thanked 2 Times in 2 Posts
Default

It will be interesting how Tadge tap dances around his previous statements about how an 8 speed auto was not needed.
Shrike6 is offline   Reply With Quote
Old 12-07-2013, 08:41 AM   #14
runutzzzzz
CF Senior Member
Support Corvetteforum!
 
runutzzzzz's Avatar
 
Member Since: Oct 2004
Location: Haymarket Virginia
Posts: 8,573
Thanks: 0
Thanked 10 Times in 9 Posts
Default

Quote:
Originally Posted by Shrike6 View Post
It will be interesting how Tadge tap dances around his previous statements about how an 8 speed auto was not needed.
It's not "needed" LOL

My next C7 will be a automatic!
runutzzzzz is offline   Reply With Quote
Old 12-07-2013, 08:48 AM   #15
DocHolliday
CF Senior Member
Support Corvetteforum!
 
DocHolliday's Avatar
 
Member Since: May 2013
Location: Fairfax VA
Posts: 2,271
Thanks: 0
Thanked 18 Times in 9 Posts
Default

Quote:
Originally Posted by runutzzzzz View Post
It's not "needed" LOL

My next C7 will be a automatic!
I switched to an automatic with this car and love itÖI wouldn't go back to a manual in a million years.
DocHolliday is offline   Reply With Quote
Old 12-07-2013, 09:09 AM   #16
ByByBMW
CF Senior Member
Support Corvetteforum!
St. Jude Donor '06-'08-'10-'11-'12, '14-'15-'16
 
ByByBMW's Avatar
 
Member Since: Dec 2004
Posts: 4,697
Thanked 11 Times in 11 Posts
Default

IF true, and I don't understand half of what that article said, then my decision to wait before buying the C7 will have been justified. I will wait for that transmission.
ByByBMW is offline   Reply With Quote
Old 12-07-2013, 09:26 AM   #17
Shaka
CF Senior Member
 
Shaka's Avatar
 
Member Since: Nov 2002
Location: FLL Florida
Posts: 1,459
Thanked 8 Times in 7 Posts
Default

Will we hear from the DCT loons?
Shaka is offline   Reply With Quote
Old 12-07-2013, 09:36 AM   #18
MikeyTX
CF Senior Member
Support Corvetteforum!
St. Jude Donor '06-'07-'08-'09-'10-'11-'12-'13-'14-'15- '16-'17
NCM Lifetime Member
 
MikeyTX's Avatar
 
Member Since: Sep 2005
Location: Slowly driving my way around the United States
Posts: 24,602

Thanked 432 Times in 348 Posts
Default

Quote:
Originally Posted by peter pan View Post
Awesome looking forward to the new tranny
....... Oh really ?
MikeyTX is offline   Reply With Quote
Old 12-07-2013, 09:37 AM   #19
MikeyTX
CF Senior Member
Support Corvetteforum!
St. Jude Donor '06-'07-'08-'09-'10-'11-'12-'13-'14-'15- '16-'17
NCM Lifetime Member
 
MikeyTX's Avatar
 
Member Since: Sep 2005
Location: Slowly driving my way around the United States
Posts: 24,602

Thanked 432 Times in 348 Posts
Default

Quote:
Originally Posted by Shaka View Post
Will we hear from the DCT loons?
Oh I'm sure ......... Once they wake up......
MikeyTX is offline   Reply With Quote
Old 12-07-2013, 10:15 AM   #20
W88fixer
CF Senior Member
 
Member Since: Nov 2013
Posts: 2,025
Thanked 64 Times in 36 Posts
Default

Quote:
Originally Posted by DocHolliday View Post
I switched to an automatic with this car and love itÖI wouldn't go back to a manual in a million years.
I had thought about waiting till 2015 but the ďbugĒ got me and I went ahead and do have the auto coming. I suspect succeeding years of Vettes will get better so I could use new features as an excuse to wait and wait and donít want to. I guess I could rationalize and say Iím getting a proven transmission rather than a new product.

Not being catty here, I hope the new transmission is perfect out of the gate. Iím sure Iíll really enjoy what Iím getting. Don
W88fixer is offline   Reply With Quote
Go Back   CorvetteForum - Chevrolet Corvette Forum Discussion >
Reload this Page
  • 8L90 in the 2015 Chevrolet Corvette !!!
  •  
     
    Reply

    Related Topics
    Thread Thread Starter Forum Replies Last Post
    C6 Z06 Frequently Asked Questions(FAQ) LTC Z06 C6 Z06 Discussion 58 09-15-2016 12:28 PM
    Camaro ZL1ís 10-Speed Auto Shifts Faster Than Porscheís PDK Force-1 Off Topic 57 05-15-2016 06:49 AM
    2017 camaro ZL1 looks pretty impressive. JerriVette Other Cars 29 04-05-2016 03:08 PM
    Z06 Article with Transmission and Engine Data RubberBill C7 Z06 Discussion 6 06-14-2015 06:18 PM
    Kens Weekly News - Sept 1, 2005 - ENJOY!! Ken Fichtner Ken's Newsletters 7 09-12-2005 12:22 AM


    Thread Tools Search this Thread
    Search this Thread:

    Click for Advanced Search

    Posting Rules
    You may not post new threads
    You may not post replies
    You may not post attachments
    You may not edit your posts

    BB code is On
    Smilies are On
    [IMG] code is On
    HTML code is Off
    Trackbacks are Off
    Pingbacks are Off
    Refbacks are Off

    Forum Jump


    All times are GMT -4. The time now is 08:30 AM.


     
    • Ask a Question
      Get answers from community experts
    What's your question?
    Send