Going downhill

Piggybacking a question on top of this. If you are in too high or too low of a gear on the descent, can you change the gear on an automatic or are your SOL?

 

As a general rule, an auto won't shift if it can't make the next gear.

The whole "never downshift on a grade" is largely least common denominator teaching. While it's not a best practice, any competent driver knows how to do it safely. Get the rpm down, drag some brake to avoid accelerating, and make the shift. Do the same thing on an auto and it will drop a gear just fine.

Note that all depends on being in control and realizing early on you're in too high of gear. The reason for the "don't downshift" teaching is so drivers who are already in deep trouble (brakes hot, speed too high) don't consider an unmakeable downshift while in panic mode. That's throwing gasoline on a fire!

 

As snow was mentioned, always leave enough RPM to recover from a trailer slide, never go down hill close to your max RPM.

Why this is important.

With a Jake or not, more RPM will have more hill holding ability than lower RPMs. Most of the engine braking in a car is actually the vacuum pulling against the closed throttle body, something you don't have in a diesel this the need for a Jake or a retarder.

If you are using your Jake in slick conditions or at a high RPM (bad ideas) you need to be ready to push the clutch in or give it some throttle if you hear the RPMs drop, meaning your powered axle is sliding.

Also do NOT have your power divider or lockers engaged going down hill. Not only does this limit the ability of your ABS to work, any slide of your drives is much harder to recover from.

Even with an open axle, the sum of both wheels has to be twice the input RPM x gear ratio. If you have your power divider in, both tandems will lose traction and you will hear RPMs drop.

The reason I will only drive manuals in winter conditions is because pushing in the clutch is the easiest way to start a recovery from a skid of the drives. Not sure how you deal with this with automated manuals but shifting an Allison into neutral will help if you have this in muscle memory.

The biggest two things to remember is to slow down and dramatically increase following distance. Close behind those two is don't ignore leaks, preserve you pressure in any way possible and make sure you have well adjusted brakes.

If you have any tools in your truck, 7/16 wrench, wheel chocks and the knowledge on how to adjust the slack is critical if you swap trailers.

A leaky can on your steer will kick out your drives with ease and trailer skids are never fun.

Fight complacency and get-there-itis and slowing down are some of the hardest things in this career. When in doubt slow down before you crest the hill. It is always easier to pick up speed than to recover from skids.

Setting personal limits and shutting down when you are uncomfortable is also hard but critical to not only a long career but a long life.

This has been a hard winter in the Rockies and way too many people have been hurt this year.

 

I have a Cummins 8.3 ISC paired with an Alison 6 speed. I have had white smoke before, I can't recall the exact description but get your exhaust brake looked it. It may only be partly closing. I don't think the white smoke is disastrous but its chalk and cheese when the brake is working 100%, and that makes your auto far safer and easier to drive. Plus spares the brakes so extends the life of them saving money.