2012 5.3L Yukon XL
The Mrs. and I are looking at stepping into the TT realm with our two little ones. We've got a new Yukon XL with the 5.3L package. I'm unsure about the ratio, so i'll have to check the sticker at ho...
Forum Discussion
RoyJ wrote:
Could you please elaborate on that one? Did GM put in a weaker torque converter in the 6L80 than the 4L60? If so, that's really not smart... Otherwise, the torque converter sees the total gearing effect from transmission x rear end. If my transmission 1st is 20:1, then I can run a 1:1 rear end and my converter would be super happy.
I don't know what the specs are on each TC, but I wouldn't think that it's "weaker". The difference, is that the steeper the gearing after the TC, the less it "slips", and therefore the less it amplifies torque. The tuning on the 6-spds locks the TC very quickly, and can do so in all gears. The 4-spd autos use an unlocked TC very aggressively, especially in lower gears... but not the 6-spds.
My statement was really just to point out that gearing in an automatic can't be compared the same as a "straight shift", since the TC is a variable torque multiplier, and will work (and be tuned) differently as you get less "slip" between the drive shaft and the motor. I could see the future 9/10 speeds barely using a TC at all.
