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
APT wrote:
Towing with the torque converter unlocked for long periods (a minute maybe?) is not recommended.
Not trying to argue (really), but the 4L60 never locks the TC in 2nd, and I've pulled a mountain at high altitude for maybe an hour in 2nd w/ 7000 lbs behind me w/ a 4L60/3.73 truck. We topped 10,000 ft, and temps never got high enough to be a concern (to me). Of course, ambient temps weren't very high up there! Running w/ a TC unlocked doesn't hurt anything if the cooler has the capacity to handle it, but it's not as efficient for mpg.
That said, I absolutely agree that you're better to have the TC locked for both heat and efficiency. The 6-spds allow that, with their tighter gearing and clutch/clutch designs.
