I would say you spend quite a bit of time in 5th and 4th while you're driving up steep mountain grades. Sometimes even 3rd might be appropriate. The idea is that it's holding you in the gear as you climb because you can't maintain that speed in the next higher gear. What did you find? Did you want it to shift more, less or was it about right? If you're not used to it, there can be a sense that it should shift into the next higher gear, but almost always it would just have to downshift again back to the gear you're being held in.garco 57 said:I would like to hear from some owners that have driven in steep mountain grades like on I 70 from colo. sprgs. to aspen or something like that. Just wondering how the tranny shifted and what gear it stayed in.