GM Builds New Six-Speed Rear-Wheel-Drive Transmission
YPSILANTI, Mich. - General Motors’ (GM) Ypsilanti Transmission Operations is producing a new variant of its Hydra-Matic rear-wheel-drive six-speed transmission. The new 6L90 six-speed electronically controlled automatic transmission is standard in the all new 2007 GMC Sierra and Chevrolet Silverado heavy-duty pickups.
Advantages of the new 6L90 transmission include improved fuel economy, performance and handling:
* The 6L90 transmission has a wide overall ratio spread of 6.04, compared to 3.31 in the previous 4L80 used in the heavy-duty pickup trucks. This allows a “steep” 4.03 first gear, which provides an improved performance launch feel.
* With this wide ratio spread, there are smaller steps between the gears, optimizing the gear ratio for towing, providing good shift quality, and maximized acceleration and fuel economy.
* With two overdrive gears – fifth and sixth – engine rpm is reduced by approximately 19 percent at 60 mph – a reduction of about 400 rpm. A lower engine speed reduces engine wear and improves fuel economy. Engine noise is also lower during cruising.
* The 6L90 has the capability for Driver Shift Control (Tap Up/Tap Down), Tow/Haul Mode, Auto Grade braking and uses DEXRON VI premium fluid, which has been validated to improve durability and provide more consistent shift performance in extreme conditions.
The GM Ypsilanti Transmission Operations (YTO) has produced nearly 200,000 transmissions since it opened in January 2003. The plant employs 500 people. YTO currently produces the 6L80 six-speed transmission for the Cadillac Escalade ESV and EXT; the Cadillac XLR and XLR-V; the Cadillac STS-V; the GMC Yukon Denali; and the Chevrolet Corvette. It also produces the 6L50 six-speed transmission for the Cadillac STS and the SRX.
General Motors Corp. (NYSE: GM), the world’s largest automaker, has been the global industry sales leader for 76 years. Founded in 1908, GM today employs about 284,000 people around the world. With global headquarters in Detroit, GM manufactures its cars and trucks in 33 countries. In 2006, 9.1 million GM cars and trucks were sold globally. More information on GM can be found at www.gm.com.
Comment by chevytruck91 on 25 April 2007:
I think this will also be in the new camaro’s, per scott settlemire (sp)
Comment by rickthibault on 2 May 2007:
Wow. That really should help with fuel econonmy and paerofmance. I hope there’s a company that gets on the ball so it can be used in street rods too! Let’s just hope Chevy isn’t doing their typical rush to get the new product to market and then give the customer a bunch of guff when they try to get it repaired because it’s prone to failure due to lack of testing and bean counters saying what parts should go inside to save $$.
Comment by 2001rotax800 on 15 May 2007:
That is amazing. What a great idea. It’s too bad that people do not compare apples to apples when they are buying Cars/Trucks. I see alot of people driving belly buttons (AKA dogde quad cab’s) I call that because almost everybody has one. For the $ you cannot beat Chevy. Iknow that is all I will ever have in my driveway!!!
Comment by Roadrunner Ariz on 3 June 2007:
I bought a new generation 2007 Vortec Max 6.0 Silverado 1500 in January 2007 and wish they had that transmission then. I have the heavy duty four speed and dislike the take off lag when you put the pedal to the metal. Do you any of you know if there is a way to get rid of that lag from start up? Disgusting when my Son and his new Nissian Titian can beat me off the line with a much smaller engine! Moreover,his has a five speed very smooth shifting automatic. I am surprised GM dropped the ball knowing the Tundra was coming out to compete with the USA Big Boys and went witht he four speed automatic. The Tundra was introduced with a 6 speed automatic.
Comment by tullycars on 30 November 2007:
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