Tow/haul Not Working

[Cosmic Charlie]

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

[06jimmy]

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 !

[Noeltrejo350]

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]

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]

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 August 7, 2022 by vucelick