Allison B500 and RPMs (Moved from repower topic)

[belfert]

Belfert- the 6th gear on the B500 is only used for high speed travel.  Allison does not want the transmission to go below 1,400rpm in 6th since it is a double overdrive.  So in your case, it would shift into 6th at close to 80mph and down shift back out at about 68mph.  Personally, don't think it's worth it.  Good Luck, TomC

I made a new topic so not to trample on Brian Diehl's topic.

I certainly would never drive much faster than 70 MPH if that.  In my book, high speed would be 60 MPH and up.  I'm not sure why Dina's engineers put in gearing that doesn't allow use of the 2nd overdrive. 

It certainly makes no sense to try to get 6th gear enabled if it won't do me much good.

[luvrbus]

Belfert, you need the 4.30 or 4.56 gear to use the 6th gear and it probably wasn,t available for your bus at the time

[belfert]

I believe the 4.10 gearing was the only option.  The Dina engineers who designed the bus told me I have 4.10 gears without even asking for the serial number (last 5 digits of VIN).  If I had 4.30 or 4.56 gearing with the 2nd overdrive I probably would not get any better mileage than the 4.10 gears and single overdrive.  I was hoping I could get a little better MPG on the flats with 6th gear, but I guess not.

What gear ratio do the newer MCI/Prevost/Van Hool buses with Series 60 and the fulll 6 speeds of the B500 have?  I don't know if Dina ever enabled the 6th gear when they went to the larger 12.7 S60 in 1997 or future years until the model was discontinued in 2000 or 2001.

[H3Jim]

Not sure of my gearing, but at 65 mph im 6th, I turn about 1550 rpm

[buswarrior]

4.56 is popular for a Series 60/ B500 stock install.

With that gear, 5th and 6th overlap nicely above 60 mph, allowing 6th for economy, or a shift to 5th for power at the same road speed.

The ones I drive will do the governed 69 mph in either gear.

happy coaching!
buswarrior

[Busted Knuckle]

Well as y'all know I have a lead foot (especially when the coach is empty), and I was satisfied with the way our new Setra was set up when we purchased it! It was set up for 75 mph on the cruise and 79 mph on the pedal! Well I haven't touched any settings at all! I stopped in a friends Bus Re-Manufacturing Facility (that's what the sign by the door says!) on the way home from my 12 day trip in MO back in June. Just for kicks & giggles we hooked up his Proreader to it and could not get any readings what so-ever from the computer! He was surprised that it ran at ALL, let alone as well as I told him it did, and that he could tell from seeing it himself! Well I told him of the turbo fire in the  engine area, and that the PO's mechanic had done some pretty half a** reworking of it. Also I told him of the wiring harness that when it gets extremely wet causes the engine to rev up to 1,000-1,200 RPM on it's on at idle, and one time it wouldn't start and I shook the whole harness and it fired right up. He and I definitely agree that as soon as time allows that harness will be replaced or at least rewired! Well funny thing happened the other night! I was empty and coming home in a steady rain and I felt like I was moving along faster than usual and I looked down and the tach said I was doing 2,300 RPM in 6th, boy I felt like I was back in the ol' Setra with the 550 HP 8V92 DDEC! (VRRRROOOOM I was pass'n everything LOL!) It was humm'n right on down the road! I don't know how fast as the speedo only shows 80, but was movin on out better than that! It does 75 @ 1600 RPM on the cruise! And I can confirm about the up shift/downshift between 5-6 th when I am try'n to behave and set the cruise around 55-60 mph on the rolling hills it goes back and forth like crazy! I usually just speed it up to keep it in 6th, but sometimes I reach over and put it on manual mode and lock it in 5th! FWIW
  BK 

[belfert]

You were going how fast in a bus!?  You're going to get spanked big time if you ever get pulled over since you are driving a commercial vehicle unlike most of us.

I can imagine 2300 RPM in 6th gear would really be flying.  I haven't researched the governed speed on a Series 60, but I didn't think it could even do 2300 RPM.

[H3Jim]

mine will do 2300 rpm, but its right around there it will automatically upshift if youre not in 6th.  I too have burined the speedo, mine goes to 85. I think I was doing a bit over 90.

I hate to think if I needed brakes at that speed, they'd just burn up immediately.  Wide open 10 lane hwy, no traffic, lots of hills.  I-15 north of San Diego.

[belfert]

I've buried my speedo plenty of times, but it only goes to 80 MPH and is at least 10 miles per hour slow.  I generally use a handheld GPS as my speedometer.  At 70MPH on the GPS my speedo will be maxed out.

[Dallas]

I've buried my speedo plenty of times, but it only goes to 80 MPH and is at least 10 miles per hour slow.  I generally use a handheld GPS as my speedometer.  At 70MPH on the GPS my speedo will be maxed out.

Brian.....

Your talking about Bryce getting spanked!
What were YOU doin' going that fast while driving with one hand and holding a GPS with the other???

Tsk, Tsk, Tsk!

[belfert]

Your talking about Bryce getting spanked!
What were YOU doin' going that fast while driving with one hand and holding a GPS with the other???

Who said I was holding the GPS?  They do make mounts for them.

I bought the GPS unit at Walmart specifically to use for as a speedo since the real one in my bus is so far off.

[Dallas]

Your talking about Bryce getting spanked!
What were YOU doin' going that fast while driving with one hand and holding a GPS with the other???

Who said I was holding the GPS?  They do make mounts for them.

I bought the GPS unit at Walmart specifically to use for as a speedo since the real one in my bus is so far off.

But you said, "I generally use a handheld GPS as my speedometer." and said nothing about a mount for it!

Besides, your so much fun to pick on! Especially after Bryce and I have gotten together!

[TomC]

4.56 with 315/80R-22.5 at 492rpm= 1,555rpm @ 65mph.  Good Luck, TomC

[TomCat]

I too have burined the speedo, mine goes to 85. I think I was doing a bit over 90.

LOL...Now I don't feel so bad about slipping my Thomas into Alabama overdrive, and reaching a terminal velocity of 87 mph. Steep grade, early sunday morning on I80. My biggest fear was losing a tire.

Jay
87 SaftLiner

[buswarrior]

Always....Always....

build up the RPM to the governor....

before slipping the tranny back into gear from ......

(fill in the blank) overdrive.

Bad noises, and spare parts on the road.....

No one tells the newbie the other half of it, only how to get into overdrive, never how to get out...

happy coaching!
buswarrior