tow haul percieved inop by customer - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat


GMC/Chevrolet Truck/SUV When starting new posts, please specify YEAR, MAKE, MODEL, ENGINE type, and whatever modifications you have made.

Reply
 
 
 
Thread Tools Search this Thread
Old 09-24-2014, 05:25 PM   #1
Junior Member
Thread Starter
 
Join Date: Aug 2014
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
tattooedtech74 is on a distinguished road
Default tow haul percieved inop by customer

i have a 09 silverado with a 4.8l and a 4l60e trans. customer believes his tow haul modes do not work because he does not see a radical rpm change when shifting in and out. called tech assist and they said that if light is on and no codes that is indeed functioning. is there any way to see if it is in fact in tow haul mode.
tattooedtech74 is offline   Reply With Quote
Old 09-24-2014, 06:41 PM   #2
Senior Member

True Car Nut
 
2kg4u's Avatar
 
Join Date: Sep 2006
Location: Windsor, Ontario / Detroit, Michigan
Posts: 4,804
Thanked 220 Times in 181 Posts
2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of
Default

Tow haul should lock you out of overdrive. If you are cruising in overdrive and hit the switch the RPM'* should go up.
2kg4u is offline   Reply With Quote
Old 09-24-2014, 08:08 PM   #3
Senior Member
True Car Nut
 
rjolly87's Avatar
 
Join Date: Jun 2003
Location: Las Cruces, NM
Posts: 6,857
Thanked 298 Times in 246 Posts
rjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant future
Default

http://www.chevrolet.com/content/dam...ado_owners.pdf
Quote:
Tow/Haul Mode
Vehicles with an automatic transmission have a tow/haul
mode. The tow/haul mode adjusts the transmission shift
pattern to reduce shift cycling, providing increased
performance, vehicle control, and trans
From what I understand of it, it keeps the tranny from hunting around. Just screwing around with the button it tends to make the tranny hang in a gear a bit longer, and it also opens up other features too that can be set. So, when someone is cruising along and hits the button, they probably won't notice a difference.
rjolly87 is offline   Reply With Quote
Old 09-24-2014, 09:40 PM   #4
Senior Member
Posts like a Turbo
 
chevy82's Avatar
 
Join Date: Jan 2014
Location: Missouri
Posts: 396
Thanked 99 Times in 84 Posts
chevy82 is a glorious beacon of lightchevy82 is a glorious beacon of lightchevy82 is a glorious beacon of lightchevy82 is a glorious beacon of lightchevy82 is a glorious beacon of lightchevy82 is a glorious beacon of light
Default

Tow/Haul mode enables the operator to achieve enhanced shift performance when towing or hauling a load. When tow/haul mode is selected, the tow/haul switch input signal to the body control module (BCM) is momentarily toggled to zero volts. This signals the powertrain control module (PCM) or transmission control module (TCM) to extend the length of time between upshifts and increase transmission line pressure. Cycling the tow/haul switch again, or cycling the ignition switch disables tow/haul mode and returns the transmission to a normal shift pattern. Watch your data in the bcm, pcm, and tcm when commanding it on.
chevy82 is offline   Reply With Quote
Old 09-25-2014, 08:12 AM   #5
Senior Member
True Car Nut
 
jwfirebird's Avatar
 
Join Date: Dec 2009
Location: western,ny state
Posts: 9,616
Thanked 563 Times in 481 Posts
jwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond repute
Default

im not sure they lock out 4rth either, the 2500hds we have at work still have 4rth just shifts hard and at higher rpm. hard to notice if you dont have a load
jwfirebird is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Tow/ Haul quit working 2000 GMC Sierra / Chevrolet Silverado ymmot04 GMC/Chevrolet Truck/SUV 7 06-03-2013 09:24 AM
What do the 14' U-Haul Trucks have under the hood? Hans Lounge 5 04-15-2005 01:24 AM
Towing U-haul? alec_b 1992-1999 2 02-18-2005 07:49 PM
bonneville's and u-haul trailers? armyguy2us Performance, Brainstorming & Tuning 32 12-30-2004 05:27 PM
F-150 vs. U-Haul Burgundy_Boat General GM Chat 2 02-07-2003 06:21 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

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



All times are GMT -4. The time now is 12:13 AM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.