Automatic trans question

[goldgiter]

I have driven big trucks in the past[car hauler for a few years] but have never driven a detroit with an automatic.
I am aware that the engine likes rpms' because the old Freightliner I drove had a detroit in it.
My question is should I manually shift my Eagle when going uphill to keep the rpms' up and when going down hill to help control the speed.
Hope this isn't a stupid question, I did a search before asking and didn't find anything.

Wes

[luvrbus]

That is the way to drive it Wes saves lugging and heat build up on both the transmission and engine ,what no Jakes  even with Jakes you need to downshift

[Scott & Heather]

What cliff said. I absolutely have to shift mine manually. It shifts dumb..way too early.  Our new bus has the push button ATEC 748 Trans and I love it. Shifts perfectly and silky smooth everytime. But I know some day I'll have ATEC woes.


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[goldgiter]

I wondered about that too Scott just wasn't sure how much manual shifting I should be doing.
If it won't hurt anything I would just as soon shift it manually all the time!
Clifford I don't have jakes, I love the way they sound tho'.

Wes

[eagle19952]

I wondered about that too Scott just wasn't sure how much manual shifting I should be doing.
If it won't hurt anything I would just as soon shift it manually all the time!
Clifford I don't have jakes, I love the way they sound tho'.

Wes

I run mine thru the gears on the flats and when i get to road speed i shift the selector into 2nd... when i hit a hill it's already to do it's job..i lose a very small amount of road spreed that way...

[goldgiter]

Eagle would you explain a little more about the shifting into 2nd, does the trans not downshift when you do that?

Wes

[luvrbus]

Oh the joy I had of having a Eagle with 8V92 and the Stone/Bennett electric over air shifter I loved that little switch on the dash   

[eagle19952]

Eagle would you explain a little more about the shifting into 2nd, does the trans not downshift when you do that?

Wes

holding the throttle steady, nope, not till the rpm drops under load...(the hill being the load)....

[goldgiter]

I'll be darn, guess I will have to give that a try!

Wes

[luvrbus]

What happen to 3rd gear that is the best gear you have on a 740 in a Eagle with 3:36 rear gears,they will run 60+ mph in 3rd that gives you a good run at a hill even with a 8V71 

[goldgiter]

I got a 6v92t, couldn't afford the v8 model!
I was wondering about the 3rd gear thing also.

Wes

[eagle19952]

mine will shift out of 1st to third in the first gear hole .. same as 2nd hole..goes right into 3rd without doing a thing except hold the throttle.

4th you have to engage.

[TomC]

Even a mechanically controlled Allison transmission has safeguards. I know if I have it in 1st with the gear shift, if I rev it to 2,400, it will up shift. On the other side, it will not down shift until a safe RPM that is set in the transmission-no matter where the gear shift is. Allison transmissions are pretty bullet proof.

Example-let's go through one cycle of an automated trash truck doing residential pickup. The PTO is already engaged to run the hydraulic pump. The truck comes up to the house. The driver pushes the lever to extend the arm to the trash can. That locks the brakes, puts the transmission in neutral, deactivates the accelerator and raises the engine RPM to 1,000rpm. Then when done, the engine RPM goes back to idle, the transmission goes into gear, the accelerator reactivates and the brakes release. This all done 100's maybe into the 1,000's of times a day.
Same with a transit bus. When the bus stops and opens the door, the brakes lock and the transmission goes into neutral (some do, some don't). Then when the door closes, the brakes release and the transmission goes back into drive.

[luvrbus]

Right the pto is engaged but the torque converter goes into lockup when the brake is applied nothing on the hydraulic system will work on a trash truck if the brake is not applied