I live in the mountains at high elevation, and often need to go several miles on steep grades, sometimes for 15-20 minutes. I've been using tow/haul and O/D off, but what RPM is the maximum I can use for extended periods without damaging anything. Plus, my tach doesn't have a redline on it, which I thought was weird. Should I avoid going past a certain number? This is for an '06 Power Wagon. Thanks.

 

Steep mountain grades can be tricky. I'd just slow down a little and use good judgment. I wouldn't be trying to maintain the speed limit and letting my RPM's stay at 5000+. That just doesn't make any sense.

There is a big difference between towing and dragging. Most don't know the difference.

If it were me, I'd try to keep the revs under 4K and watch the temp gauge like a hawk. How much are you towing?

 

As Doc said above, deffinitely keep it under 4k rpm. While the new engines are capable of being pushed, extended high rpm periods aren't that good for it, especially if its not fully broken in.

 

Thanks, guys. I don't do much towing, but on high mountain passes (11,000+ feet), even the Hemi loses some of its oomph. I just want to maintain a reasonable balance of speed and RPM that won't hurt anything. For now, I'll just try to keep it under 4K.