Question about 6 speed auto

Truck916 · August 28, 2016

Since its been out longer...does it seem to have less issues than the 8 speed. I'm looking for a crew cab 5.3 2wd and would like to keep the truck for awhile.

I went and test drove the Tundra, Silverado and F150. Love the size of the Silverado. Not as big as the other two...seem to be overkill. Just been a little scared about dropping 40 on a truck and not being happy with the tranny.

11bDad · August 28, 2016

Considering how long the 6L80 has been out and all the different platforms it's used in, there are a s**t load of them out there. I would assume the majority of them have functioned properly. It takes a little getting used to since 5th & 6th are overdrive gears. I don't much care to be in 6th gear at 40 mph, so I'm usually in M5 until 55mph. I've had the confused downshifting, and 2-3 flare, but mine has usually been quite smooth. GM decided in 2014 to add a thermal bypass valve, which increased the normal operating temps to 190+. I was never comfortable with these higher temps despite everything I had read saying it was normal. My tranny took a crap when I was 100 miles from home. Truck had 10K miles on it when this happened. Torque converter and pump were replaced under warranty (4 trips to 2 dealers). I added a 20K btu Tru Cool transmission cooler and modified the thermal bypass valve in an effort to cool the thing down. Since I made those changes, the confused downshifting has almost completely disappeared, and the 2-3 flare shift only happens occasionally. I haven't towed anything with it yet, so I can't offer any info on that issue. I can say cooling it down has made a big difference. You'll probably get a good one. Good luck.

diyer2 · August 28, 2016

Used 2012 Sierra(41K miles at purchase) 5.3L six speed trans. 50k miles. No complaints, tow a boat, city, mountain, freeway.

KnappAttack · August 28, 2016

I love the 6 speed in my 14. No complaints or problems at all. I run E85 all the time now, as the FlexFuel was standard in the 14's, it makes a whole bunch more power on E85 and the trans seemed to change programing to compensate for the added power, it firmed up the shifts and seemed to change its calibration for the power increase. First tank of E85 was slushy shifting and slipped, as I kept using and driving with E85 the trans seemed to adapt better and change with the added power.

The 6 speed in my truck is much better than the 8 speed in my Audi A8 for sure that much I know. I hate that 8 speed in my car! It is herky and jerky never knowing what gear to go into when downshifting.

Donstar · August 28, 2016

If given a no-cost choice between the 6 or 8 speed automatic, I would choose the 8. I think we'll see the 6 join the 4 soon. The number of speeds in the automatic transmissions have increased steadily over the years and next there will be a 10 speed in our trucks. I personally would prefer a manual transmission!