Mountain Grades

So I may be temporarily switching to OTR bc of Coronavirus but a little worried about the Rockies and mountains like it I originally drove the Great Lakes for 2 years but now I’ve just been doing Vegas to Los Angeles I have a 10 speed freightliner cascadia for the mountain pass and cajon pass I usually just drop to 9th gear and jake when I’m heavy and that tends to hold was just wondering if the different mountains would require lower gears? Thanks.

I don't deal with mountain passes but the advice I've always seen posted is go down the hill in 1 gear lower than what you climbed it in. For instance you reached the top in 8th gear. Go down in 7th.

Yes, use the transmission (that lower gear} to control your speed. Brakes are for stopping, not controlling downhill speed. The best thing to use is the engine retarder ("Jake brakes").

If you see a "TRUCK SPEED LIMIT" sign on the downhill leg, that's your speed limit (yes, even 35 MPH on the interstate). Remember the "Mountain Driving" party of the CDL manual:

Proper Braking Technique
Remember, the use of brakes on a long and/or steep downgrade is only a supplement to the braking effect of the engine. Once the vehicle is in the proper low gear, the following is the proper braking technique:

• Apply the brakes just hard enough to feel a definite slowdown.
• When your speed has been reduced to approximately 5 mph below your “safe” speed, release the brakes. (This brake application should last about 3 seconds.)
• When your speed has increased to your “safe” speed, repeat the first two steps.

Regardless of how fast or slow other trucks might be rolling, you drive your truck the way you are comfortable. Even a little respectful fear is a good thing.