Thread Tools Search this Thread Display Modes
Old 08-05-2003, 01:45 PM   #1
Silvertwinkie's Avatar
2004 25' Safari
. , Illinois
Join Date: Feb 2003
Posts: 10,381
Tow/Haul feature on GM vehicles

I was looking at the GM site today and found what the tow/haul feature does:

Go into the Allison transmission section.

Tow haul in essence locks the torque converter after 1st gear to keep the trans from overheating due to being unlocked.



Computers manufactured by companies such as IBM, Compaq and millions of others are by far the most popular with about 70 million machines in use worldwide. Macintosh fans note that cockroaches are far more numerous than humans and that numbers alone do not denote a higher life form. -NY Times 11/91
Silvertwinkie is offline   Reply With Quote
Old 08-05-2003, 06:48 PM   #2
3 Rivet Member
Join Date: Mar 2002
Posts: 113
Images: 3

I can't speak for the Allison, but in the gas engines, tow/haul simply modifies the transmission shift program to adjust for heavier loads and does not prevent the transmission from dropping out of lockup. In my 03 3/4 Surburban, regardless of whether or not tow/haul is selected, the transmission drops out of lockup based on speed (typically between 45 and 50 mph). It does not drop out of lockup in either 3rd or 4th gear under load (different from light duty vehicles). Increasing throttle position under load only forces a downshift to the next lower gear.

alan is offline   Reply With Quote
Old 08-06-2003, 10:06 AM   #3
4 Rivet Member
Jabba's Avatar
1955 30' Liner Commodore Vanderbilt
Wayne County , Michigan
Join Date: Sep 2002
Posts: 421
Images: 17
It doesn't hurt mileage either!

I checked our gas mileage after our run this weekend, ran it in Tow/Haul mode the whole time and got 15.1 MPG with a full tank of water, 2 full LPG tanks and everything else, I was ecstatic to say the least! It was a mixture of freeway and secondary roads. Can't beat that!
Jason & Veronica J.
S.E. Michigan
1955 Commodore Vanderbilt 30'
TAC Member MI-6
2008 Chevy Silverado Ext. Z71 w3.73
Jabba is offline   Reply With Quote

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search
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
Dual Alternator Kit Available for GM Trucks Pick Tow Vehicles 1 10-22-2003 09:11 PM
GM: The official tow vehicle for Airstreams! :) Silvertwinkie Our Community 8 10-05-2003 10:10 PM
Design feature or possible Nightmare?? Jason1101 General Repair Forum 5 01-13-2003 05:04 PM
New forum feature? airstreamcaravel Our Community 1 11-02-2002 11:22 PM

Featured Campgrounds

Reviews provided by


This website is not affiliated with or endorsed by the Airstream, Inc. or any of its affiliates. Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.

Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 05:14 PM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.