Company removing manual gear selection override on automatic trucks?

I was taught the lite steady brake pressure 10psi or less and you can ride the brakes all day without them overheating. The snubbing method is not so good on snow or ice road because you could lock the brakes up vs lite steady pressure.

You avoid the worry about jacknife by teaching drivers the same thing they told me 20 years ago. You don't use the engine brake in slippery condition. You use the truck brakes.

 

Didn't read all the posts yet but the autos I've driven all had manual up and down arrows to lock in the desired gear. I didn't know you could disable that and it sounds insane. The autos I've driven did not have engine brakes and were terribly underpowered. Climbing hills they'd rev up, shift up, lug, downshift and downshift again and you'd struggle the rest of the hill, in a gear lower than you wanted, making sure you didn't rev past 16 or it would shift up again, lug, downshift and then downshift again, until finally you'd be crawling along in 1st or 2nd.

Going off the hill in 2nd with no way to lock the gears means having even that little bit of engine back-compression to help hold you back taken away. Ride the brakes the whole way while the transmission upshifts over and over and hope the brakes last until the bottom of the hill? Insane!

 

We have been wanting an automatic for awhile. But I'm scared as hell after reading all the complicated things you have to do to descent a hill. Some say leave in cruise control , use Jake don't use Jake and many other combination of technique. Might just stick with our 10 manual awhile longer.

 

When drivers get in the bad habit of using the Jake brake in snow and ice they are the one saying a autoshift is unsafe because they don't like how it works. They blame the autoshift instead if admitting they are driving wrong

It's basic driving skills you don't use the engine brake in slippery condition. Now you can use the autoshift like it supposed to be used. You can let it downshift and let the computers bring the engine RPMs up to 2200.

Remember we are talking about the Detroit transmission and I would guess the Volvo ishift is about the same. These transmission have a big advantage that Eaton does not. These transmission communicate and can control the engine. That's why you don't get all the crazy shifting like the Eaton autoshift.

 

It's only ever going to get up to 2200 rpm if the jakes are on.

So if it is rainy/snowy conditions, plus add in you cannot set it in Manual mode, the only other choice is to manually downshift it going down the grade, it will auto upshift on its on over and over again unless you have pressure on the brakes the whole way down to "lock" it in gear with the sensors.

Now we know from our training to use Snub braking, not constant braking so this flies in the face of our training.

I think the main debate here is a company locking out or disabling the driver's ability to change it from Auto mode to Manu mode. Taking away a huge amount of ability and tools from the driver.

I went down a snowy hill in mine in January (just picked up the truck January 1st) so still learning how to drive it at that time. I tried to use jakes but it would aggressively downshift and run up to 2200 rpms. Didn't appreciate that so turned jakes off. Didn't know about the manual mode thing but did try to downshift multiple times but it would just upshift automatically on me as we gained speed downhill. Used the brakes wayyy too much on that run. Pulled over to pee and noticed brakes were smoking a little.

Haven't hada problem since learning how to set it in Manu mode with jakes is very similar to running a manual truck with jakes, it is in the gear I want the rpms I want, none of this aggressive downshifting, or auto upshifting against my wishes.

I have even taken to set it in Manu mode for California 55, one gear down to 11th (DT-12) and the fuel economy is stellar, and plenty of power in rolling hills terrain, none of this lugging down thing.

I would agree, I would refuse an AMT that has the manual mode disabled.

 

I was going down train pass one day with my volvomatic. Stupid truck decided to shift a gear up. I caught it before it got away from me and brought a gear down.

 

Train pass..."tejon pass"

Spellcheck...grrr

 

So here's my video experience running this DT-12 downhill a couple different styles. I totally forgot to try the cruise control downhill trick because that is so far off the charts in my mind of things to possibly do. Will post a video tomorrow of going down a steep hill in cruise and see how it goes.

 

I'm with you. This entire thread has just reinforced my notion that I will quit driving before I get in one of these automatic clown cars. Good lord. Lol

 

It's a stupid law and teams break it all the time, just not usually while recording.