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Tow/haul Not Working

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Cosmic Charlie Enthusiast

Cosmic Charlie

Posted
Posted

I just bought a 06 Sierra and compared to other Chevy trucks I have owned with tow/haul option it seems odd the way it works. I thought at first it did not work at all, I would push it and indicator light would come on but nothing would happen ! Then I discovered it would only lock up at speeds of 50 mph or below and would automatically shift out at 58-59 mph on it own !

I had it in the Chevy dealer for a follow up on another subject and described it to the service writer, they drove it and said it worked correctly and they could not find a service adviser on tow/haul problems. And here I have read several different problems on them!

Can anyone tell me if the way mine works is correct or not !? I have had vehicles with tow/haul and they all pretty much engaged and stayed engaged until you would turn it off.

My tow/haul switch on just holds the shifting to at least 2200 rpm's so not to lug the engine ...

 

put it on an drive normal non agressive and you will find it reving higher to about 2200 rpm's before the next shift

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tjg79
tjg79

Tow/Haul Switch/Indicator Always On or Inoperative   4L60/4L60-E/4L65-E Transmission     Circuit Description Tow/haul mode enables the operator to achieve enhanced shift performance when tow

gmtech4
gmtech4

Diagnostic Trouble Code ,   Someone should supply descrip and operation , it either changes shift points or adjusts transmission oil pressure to hold clutches stronger   You can purchase Alldata.

gmtech4
gmtech4

yes but its not as obvious like ear;ier yrs where ya can see the 200 rpm jump ....its PWM now and that means its ramped up and ya dont feel it ,,,,   somebody needs to post a description and operati

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06jimmy New Member

06jimmy

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Posted

My tow/haul switch on just holds the shifting to at least 2200 rpm's so not to lug the engine ...

 

put it on an drive normal non agressive and you will find it reving higher to about 2200 rpm's before the next shift

Thanks, I will try that, I do very little towing anymore and it is light loads when I do !

  • 6 years later...
Noeltrejo350 New Member

Noeltrejo350

Posted
Posted

I have a 2004 silverado 2500 with a 4L80 & my tow haul button wont work! I replaced my shifter and still wont work? How can i check what the issue can be? 

davester Senior Enthusiast

davester

Posted
Posted

Well, you can test the wiring harness further along the chain to see if the button works, or use a more advanced scan tool to see if the bcm/ecm/tcm is told the button has been pushed, and should be able to turn the tow/haul light on the IP on/off (perhaps the bulb has burned out, I don't recall at the moment if the bulb is incandescent or LED, GM wasn't consistent in their use).

vucelick Enthusiast

vucelick

Posted
Posted (edited)

There is a small diameter orange wire that runs out of the turn signal/cruise control stalk and down the column they break near where the column tilts, repair the wire and the tow/haul will work again.  It is a pain to work with the tiny wire, and it may be enclosed in a small black wire loom.

Edited by vucelick

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