General Motors Confirms 8-Speed Automatic For Silverado, Sierra And Yukon10
Following this week’s announcement that General Motors’ new 8L90 eight-speed automatic transmission will now be used in the 2015 Cadillac Escalade, the automaker has confirmed that the transmission will also now be standard on 2015 Chevrolet Silverado, GMC Sierra and GMC Yukon Denali/Yukon XL Denali models equipped with the 6.2-liter EcoTec3 V8.
GM’s 8L90 transmission was developed for use in the 2015 Corvette Z06, but will receive small tweaks as it’s adapted for use in other vehicles in GM’s portfolio. Despite having 2 extra gears, the transmission is the same size and weight as the 6L80 six-speed it replaces.
The new eight-speed also has a 7.0 overall gear ratio, which is wider than the 6L80 six-speed, allowing for a higher first gear ratio to help drivers start more easily when towing or trailering. It also allows for a numerically lower rear axle ratio, which reduces engine RPM on the highway and saves fuel. GM says it release EPA estimated fuel economy figures for the eight-speed pickups closer to the start of production in the fourth quarter of this year.
- Sweepstakes Of The Month: Win a 2023 Corvette Z06 Convertible. Details here.
Finally!! Can’t wait to see how the 8L90 will work in the trucks and SUVs.
Why isn’t the Suburban included on this list? Is it confirmed that it will not be getting the 8 speed for differentiation purposes or was it an oversight?
I think the 6.2 was removed from the Suburban/Tahoe options this year, which would be why its not available.
So only on the 6.2L? We can’t even get a 6.2 in Canada due to lack of availability. Great 🙁
Yes, only on the 6.2 for now.
I’m kind of bummed that it is only offered on the 6.2L but remember when he 6 speed came out it was offered on the high end models.. but it later went to others, hopefully it won’t take as long as it did for the 6 speed to get across the whole line. But I’m guessing they do it on limited trucks to work out the bugs if there is any and by the time it gets to the 5.3’s and the 4.3’s it will smooth, that and building up supply is probably a major factor too.. Next couple of years we will see a 10 speeds rolling out..
Here is the deal here.
Yes this transmission is late but for several legitimate reasons.
#1 it was built by GM with funding from Ford. Yes Ford will get it soon too and it will be just a slight variation of the GM version. This is why a 2015 ford truck was seen at the Warren Proving grounds last year.
#2 GM is back to what they do best and that is transmissions. They build them in house and often sell them to other MFG to use on top of their own use.
#3 Yes Ram had an 8 speed first but they bought theirs from ZF and just tweaked it a little. Their version did not go through all the validation testing GM has put their through. GM started to cut back on this in the 80’s and they had failures. Now they are back to the testing they used to do and we will not have failure like in the past. Note Ram has had recalls and failures with their ZF box.
GM is doing a slow roll out on this and supplying the engine in most need first and will spread this transmission out to the other V8 models as soon as next year. The V6 will see it last as it is in less need of more gears.
The bottom line is with start up there is only so many transmissions and if you are going to use them you put them with the most inefficient engine first.
Note most of the delays were due to validation testing as it takes the most time of development.
GM and Ford worked together on the 6 speeds, but GM was alone on the 8. GM and Ford have an agreement to develop 9 and 10 speeds. The shared transmission project was mainly the hardware, electronics were unique to GM and Ford.
who says you can’t order a 6.2 litre with an 8 speed in Canada?………..I just did on a sierra sle…….special order!