I've noticed this a couple of times now and am a little curious. Here in Western WI we are pretty low when it comes to Sea level. We do have some bluffs along the Mississippi though that are releatively high. ANyway a couple of times I have been driving up a fairly steep grade and my truck seems to lose power. Last night for instance I was out putting up my Turkey blind and had to climb up a pretty decent grade, by the time I got to the top I had the gas almost to the floor and was barely moving. I stopped and shifted down to 2 and could barely move although the engine was revving quiet high ( did not catch the rpm's). so I stopped again, put it in nuetral and engaged the center Diff and put it in 1 and then I had all kinds of get up and go. The tires were not slipping but it was as if the power wasn't being transferred to the tires. This has hapened before going up another steep hill where it felt as though I just ran out of Power. Could it be that the transmission is not shifting out of OD when I start the climb? both times I was not going more that 20MPH when I started the climb. DO I need to stop before going up? 92 FJ 80 227K