We are taught in school to be ready for the hill and be in the required gear at the summit before you start your decent. The risk if that you take the truck out of gear and then miss your shift. Now the truck is accelerating under it's own weight down the hill out of gear. You will fry your service brakes quickly trying to slow down that truck enough to get it back in gear.
I have run into experienced driver's who claim they can downshift on downhills because "they know how to shift" but I would never risk it.
1: Don't hit anything. 2: Don't hit anything. 3: Don't hit anything. 4: Don't hit anything. 5: Don't hit anything. 6: Don't hit anything. 7: Don't hit anything. 8: Don't hit anything. 9: Don't hit anything. 10: Don't hit anything.
1: Don't hit anything. 2: Don't hit anything. 3: Don't hit anything. 4: Don't hit anything. 5: Don't hit anything. 6: Don't hit anything. 7: Don't hit anything. 8: Don't hit anything. 9: Don't hit anything. 10: Don't hit anything.
lol, love that
I drive an automatic and can shift down going down hill. Did it today with about 44k in the box. Jakes on high. Drop a gear and use stab braking as needed.
New drivers shouldnt downshift on hills because they cant find the gear. i have done it, but i wasnt going 65 down a 7%. i would.be going 25 to 35 depending on my weight and could easily shift if i meeded to slow down.
im the autos it doesnt matter
I drive an automatic and can shift down going down hill. Did it today with about 44k in the box. Jakes on high. Drop a gear and use stab braking as needed.
Automatic...Allison 5-speed? I never think of automatic transmissions when thinking about Class 8. I'm old school. I think of gear jammers and double clutchin' whenever I think about Peterbilt, Jimmy, Mack, White or Kenworth. I thought the Allison 5-speeds we had my army 900-series 5-tons were dorky. I don't dare even think about taking a clutch semi out of gear down hill.
To engage and then disengage the clutch twice for every gear change.
When double clutching you will push in the clutch, take the gearshift out of gear, release the clutch, press the clutch in again, shift the gearshift into the next gear, then release the clutch.
This is done on standard transmissions which do not have synchronizers in them, like those found in almost all Class A trucks.
I drive an automatic and can shift down going down hill. Did it today with about 44k in the box. Jakes on high. Drop a gear and use stab braking as needed.
Automatic...Allison 5-speed? I never think of automatic transmissions when thinking about Class 8. I'm old school. I think of gear jammers and double clutchin' whenever I think about Peterbilt, Jimmy, Mack, White or Kenworth. I thought the Allison 5-speeds we had my army 900-series 5-tons were dorky. I don't dare even think about taking a clutch semi out of gear down hill.
The Cascadias I drive have 12 speed auto-shift transmissions. I suspect it’s the same with Rainy’s Primate Tractor.
And to add my two cents on manual downhill shifting; unless the grade is constant (which most are not), it is likely you’ll need to change gears either shifting up or down.
Although there seems to be concern of a missed shift, once experienced and a bit more confident, downshifting while descending a grade is acceptable and if done correctly safe. The trick is to know the hill, and anticipate when the grade is about to increase and downshift before picking up speed. Like most of the skills necessary in operating a heavy truck, experience and repetition are the best teachers.
To engage and then disengage the clutch twice for every gear change.
When double clutching you will push in the clutch, take the gearshift out of gear, release the clutch, press the clutch in again, shift the gearshift into the next gear, then release the clutch.
This is done on standard transmissions which do not have synchronizers in them, like those found in almost all Class A trucks.
My truck has an Eaton Fuller 10 speed autoshift transmission. They are not the same as your regular automatic transmissions. Depending on the grade, I will sometimes put mine in manual mode, and in conjunction with the jakes, descend the hill. Sometimes downshifting, sometimes not. Most drivers will tell you not to downshift on a 6% or more grade.
Most larger companies are running autoshift now, and other ones are transitioning.
1: Don't hit anything. 2: Don't hit anything. 3: Don't hit anything. 4: Don't hit anything. 5: Don't hit anything. 6: Don't hit anything. 7: Don't hit anything. 8: Don't hit anything. 9: Don't hit anything. 10: Don't hit anything.
I fully agree. Except, at #9, I would put in GETYERBUTTOUTANDLOOK, then back to #10 as written...
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If so, I would suspect any CDL school would cover it. I ask because I have had a NRA-approved hunter safety course and there was a 'Ten Commandments of Gun Safety' we had to know. I have the same philosophy about the transportation world. I believe no vehicle, especially a heavy one, should be given any less respect as should be given a firearm, or a jetliner for that matter. I believe there are more vehicle-related serious injuries and deaths each year than such mishaps related to guns while commercial planes seem to have better safety stats than both road vehicles and firearms.
PS - Another question, does anybody here agree that under no conditions a semi should be shifted on a downgrade, that a downhill truck should stay in the same gear going over the summit that it climbed the hill to begin with? A retired truck driver once told me this years ago.
CDL:
Commercial Driver's License (CDL)
A CDL is required to drive any of the following vehicles:
Dm:
Dispatcher, Fleet Manager, Driver Manager
The primary person a driver communicates with at his/her company. A dispatcher can play many roles, depending on the company's structure. Dispatchers may assign freight, file requests for home time, relay messages between the driver and management, inform customer service of any delays, change appointment times, and report information to the load planners.