First off, I have the gas motor not the PSD. I have about 3k miles on it and I am pretty disappointed in the hill mode. It works once in a while, and is far more limited than the owners manual suggests. Below 5mph it is pretty strong when it works, but sometimes will just let go with a cluck, and you are off and running. I am assuming it is defective, but wanted to get other peoples opinions. Above 5mph, I don't think that it has ever done anything, and they say it works to 20 mph. Every time the truck gets near 20, the dash chimes at me and tells me I need to slow down for it to work. My reply to the dash is "isn't that your job?"

 

Yea,
I haven't tested it thouroughly but have the same impression - I'll be in a place to give it a good test soon .. but the times that I have tried it it seems like it doesn't really lock up well..