newbie questions about descending grades and gears

Well I know many here may disagree--but there is a very old school way of looking at downgrades--and that is--go down--one gear LOWER--then the gear you topped the hill in--while with today's modern trucks this may be overkill--it is one of those things that can keep you out of trouble--as for RPM's etc--IMHO--keep your R's well below the point you would have to up shift at--and then you can use the snub method you were taught(along with your jake)when applicable to bring your R's back down into that lower range--it take time and patience to get used to long steep grades--but it seems like you already have a pretty good handle on it--and as you do it--you will become more comfortable with it--just keep the old saying in mind--"You can come down a mountain too slow--as many times as you want--BUT--you can only come down too FAST ONCE!"

 

Best piece of advice I can think of is just start off in a way lower gear before you get to the decent, you let off the throttle with or without jake break and she slows a lot, easy enough to bring it up a gear, just remember to upshift with rpms low and do it quick. At the very first sighn you are in two high of gear jamb the breaks hard drop your RPM's as fast as possible and make the shift fast, let off the breaks and let them cool. Keep it fast. Super hard pressure on breaks, slow it down immediately shift, keep breaks cool. With experience and experience only not some bs formula you see on a trucker forum, you will know with your wheights, truck and own personal perception of the grade how to take it. Untill then start off in a super low gear when decending then bring it up as you need. Being new skipping gears when ushifting going downhill is something to keep in mind which will prevent you from missing your next gear dew to you not being that fast or other mistake.

As far as a beginner goes. I would advise all new to driving to descend slowly in a gear lower than what you need (thats when you let off throttle and truck slows, zero breaks) with flashers on. Same thing as backing, it doesnt matter how fast you are as long you dont bump into sheet you are doing terrific. Build up your comfort level and experience then slowly, slowly take it a very small bit faster. Do not be in a hurry about backing up or going downhill faster. This takes time, if you try to push it before you are truly ready than you will certainly regret it.

 

This is what my old school trainer told me many times. I used this method recently when I went on a trip and it worked really well.

 

^^^^ What he said. ^^^^

And since you mentioned what if no Jake, switch the engine fan on; The 50-75 HP it sucks up at higher rpm is worth taking advantage of as you come down. Even with the Jake working it can be used as a fine tune: it just might be enough extra drag to keep you from having to snub if the gear you're in is a smidgen too high.

 

what I do: With heavy I drop a gear when I crest top of pass, turn on jake full power. I wait to see if RPM to climb past 1700 and how fast. If my RPM jumps fast I stomp on breaks almost full force for about 1/2 second bring RPM down to 1,000 let of breaks split second downshift repeat. Sometimes I am lazy and dont want to use service breaks so I will just run jake break, I play with the jake switch all the way down. I switch it from 3 cyclanders to 2 or one till it gains then move it back to 3 till it slows down then back to 3 ets. I use it alone to controll speed. When heavy this is my prefered method.

When empty or light, I with higher gears and use jake full bore with the service break. I reley on the 10 second rule (If you gain more than 5mph in 10 seconds you are going to fast and need to downshift) to determine gear, as always starting off in lower gear and upshifting if I feel compfortable that it will hold with no problem and very little service break action.

I ran for about 3 months without an engine break which freeking sucked, never again. Without a jake break you can climb about 1/3 faster than you can safely go down depending. I almost got into trouble a few times when jake first went out, so for a few months I drove downgrades like a little sissy. I would put it into low gearbox and grawl down them 20-30 mph flashers on using 10 second rule or close to it, trucks with there jakes hammering flying past me at 45-60mph like i was standing still, really sucked but its what I had to do to survive, and or minimize cost on equipment. Driving without engine break really really really sucks! I only use service break when I have to most of my slowing ets. is engine break, i am extremely dependent on jake, even though I have and can drive without one, will never do it again

 

every gear has its speed and every speed has its gear. think a minute on this then put it to practice in your daily driving then if you find you have to shift going down a grade you should be able to know what gear to go for based on your speed. If you need to use the brakes dont stomp on them like others have suggested, just use enough force on them to bring your speed down to what you need to make the shift. if you lock any wheels, especially on the trailer, by stomping the brake and you lose traction with that trailer and your weight is up towards max gross , you my friend are in some deep poo poo!

 

Thats what I said or meant to say, to do what you thought I said or what i actually said but didnt mean is just friggen asinine guy.

After a while, you know your truck and can almost tell the weight you are pulling before you even hit the scale just by the feel. And by a while I mean a short while, one of the easyiest things to pick up for a noob. You even as a very begginner should be able to hit the right gear before any decent without any problem almost a hundred percent of the time. Your jake break breaks or stops working so you drive for first time without a jake, the first down grade probley catch you off guard. Maby a freek hill or just running long hours straight or something, feeling sick whatever you hit wrong gear, maby a couple three times a year at best.

If a driver has a hard time figuring out what gear to be in before they go down a grade, even as a beginner with no more than a couple weeks experience there whole life, they will have a really hard time driving and probley will wash out within first year of driving.

 

good explanation!!