Reply
 
Thread Tools Display Modes
 
Old 02-13-2007, 11:38 PM   #1
Mini-Skoolie
 
Join Date: Dec 2006
Location: Whidbey Island, Washington
Posts: 14
Year: 1980
Coachwork: Crown
Chassis: 3 axle (10 wheel)
Engine: GMC 6-71 T
Rated Cap: 97
Send a message via MSN to Coalforge
Allison shift point

have an Allison MT-644 behind a 6-71-T. The engine no load high
idle is about 2650 and the high idle under load is 2400. The
transmission shifts at 2100. This seems low on the power curve. I
would be interested in knowing other people's shift point and if it is low, is it
practical to raise the rpm where the shift occurs?
Thanks
Coalforge is offline   Reply With Quote
Old 02-14-2007, 12:14 AM   #2
Bus Nut
 
frank-id's Avatar
 
Join Date: Nov 2003
Location: Twin Falls, Idaho
Posts: 808
The master of Allison auto trans

A good auto trans mechanic and shop owner in your area is....
Harry at Power Shift NW... Woodinville.. 425 487 1535
When ya call him, have all the data ready to tell Harry. He wants all the info on the trans tag. Harry has the books and lots of experience. Be ready with your engine type, number, type of bus, rear axle numbers. Harry will give ya lots of information and advice. I'm going to him shortly so he can change my trans shift points. Tell him, Frank, from Idaho gave ya this information.
Frank
frank-id is offline   Reply With Quote
Old 02-14-2007, 07:00 PM   #3
Bus Geek
 
the_experience03's Avatar
 
Join Date: Feb 2006
Location: Saint James, MN
Posts: 2,669
Send a message via MSN to the_experience03 Send a message via Yahoo to the_experience03
How do they change the shift points on the mechanical
Allisons? Is it just a modulator swap like on a Turbo 400?
__________________
http://farm4.static.flickr.com/3024/...09f20d39_m.jpg
Skooling it...one state at a time...
the_experience03 is offline   Reply With Quote
Old 02-14-2007, 09:17 PM   #4
Bus Nut
 
frank-id's Avatar
 
Join Date: Nov 2003
Location: Twin Falls, Idaho
Posts: 808
Allison trans shift points

Allison determins shift points by, throttle position, govenor, engine type and application. The major adjustments are done in the valve body, with the Allison book, many years past experiences, and application. A farm truck will not have the same shifts as a bus or a local delivery truck. The rear axle ratio also affects the adjustments. Harry is da man. Frank
frank-id is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Buses that don't like to shift out of park? wirelessguyNY Ford Drivetrain 3 08-26-2011 04:52 PM
From the bacterial point of view Hex Alternative Fuels | Electric, Propane, Wood Gasification, etc. 0 12-08-2008 08:50 AM
Need suggestions for starting point.... Imaexpat2 Conversion General Discussions 15 03-02-2007 03:58 AM
I need a floor mounted shift tower frank-id Classifieds | Buy, Sell, Swap 1 06-13-2006 05:41 PM
transmission wont shift right glock17 Skoolie Conversion Projects 3 12-13-2004 11:18 PM

» Virginia Campgrounds

Reviews provided by

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 08:22 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2017, vBulletin Solutions, Inc.