Keeping RPM's down on downgrade

I got caught like that a couple times when my truck derated very slowly, and the jakes were the first thing to go. What I would have to do is press on the brakes a little longer to slow down enough to downshift and again with the brakes long enough to slow down enough to downshift again. I know it's putting a lot of energy and heat into the brakes but once I got into a low enough gear everything was OK because the lower gears offer their own compression in helping hold the unit back.

Maybe put the jakes on level 1 and be ready to turn them off first sign of slickness.

 

If it looks slick get those tires over in the rock for traction.

 

Less speed means more [equal] braking can be applied before breaching a set heat point. RPM's really has nothing to do with anything on a DESCENT unless you're engine braking. Engine brakes are more efficient at higher RPMS, like 1500-1800.

I really don't like to be in a gear that keeps me below about 1500 RPM, regardless of the grade or road condition or ascending or descending.

Descending on slick (icy) roads ALWYAS commands a slower then normal speed, given the current weight, but still lighter loads will lock up more easily with brake application then heavier loads.

Also, be advised that "wet, cold, icy brakes" can have a significant delay before they begin to grab good.

 

What cracker jacks box did you get your license from? Ok now that I got the obligatory rookie hazing comment out of the way, here is some constructive advice.

First thing. When going down hill, you want your rpms high. the engine works to slow your momentum even with the jake turned off. so drop a gear or two to keep the rpms up.
Who ever taught you to drive should have taught you how to go down a mountain or hill, but they didn't say now you are going to teach yourself.

A rule of thumb is go down a hill in the same gear you went up it. Unless of course you just dumped over 15k in your Detroit and want to show off. In which case you better stop a coyrote gears.

For the purpose of this exercise let's say you went up the hill in 75 Gear at 35 mph. 35 is your target speed. As the truck hits 40 mph, you apply steady pressure to the brake pedal to slow it back down to 35. Rinse and repeat to the bottom. but pay attention and if you notice it requires more foot pressure to slow you down, your brakes are fading. assuming you are good at shifting, drop a gear, and if not you better hit the shoulder for a complete stop while you still can.

edit: what engine is in that truck? I don't know of a single modern diesel engine that can't go above 1600 rpms.

Nevermind those loggers. they aren't gonna support your family when you go over the edge. You can go down a mountain a million times too slow, but only going down it onceotoo fast

 

Actually, you can let the RPMs run up to 1800-2000 descending...stay out of the throttle! Higher RPMs will give you more jake effect. The new engines are designed that way.

 

75th gear? Hope that was an auto shift!

Couldn't resist that one!!!!!

 

Limiting to 1500 is fine, but not necessarily necessary. A detroit can safely operate at 1700-1800 RPM for a while, no harm done. Thing is, the lower RPMs like 1200 tend to keep you in a semi-uncontrolled low-power state in the event you need to apply power (torque) to deal with a sliding situation.

 

Stupid phone. Meant 7th