I hooked up my 5th wheel today to take it in for servicing and noticed my trans would not engage towing mode. The dash light didn't come on, and the trans wouldn't down shift. After dropping the trailer off, it worked fine. My first thought is something with the trailer plug/wiring, but I don't know what. After hooking up, I engaged the 4-way flashers and turned on the lights. Then I did a walk around to make sure everything was working properly, and it was. The last time I towed, everything worked fine.

Any suggestions?

It might be a problem with the switch itself. Since it is new perhaps there is a piece of debris or something in there preventing the switch from working every time.

The tow mode does not care or know if there is a trailer hooked up or not.

Thanks Max. I couldn't think of a reason why it would cause it to not work, but was puzzled why I tried it half a dozen times with the trailer hooked up and it wouldn't engage, but the minute I unhooked, it worked without flaw. :confused: If I had looked at the trailer when connected and notice the backup lights on, or something weird like that, I would have a place to start trouble shooting. And of course since it's working now, if I take it to the dealer I'll get the "There's nothing wrong" song and dance.

TomS, I have a similar problem posted and have not received any replies. I have noted one specific on my 06 dually that you may want to check on yours. On mine the problem comes and goes with operating temperature. To test this try to shift in and out of Tow/Haul mode when the engine is cold or at least has not run for 4 or 5 hours. Mine works great in this circumstance. Now drive the truck and get it up to normal operating temperature for both the engine and transmission. Now try it. Mine has all kind or problems at this point, only randomly engaging and disengaging after probably 50 pushes of the button on average. Let me know the results if you try this. BTW, mine goes to the Stealer in the morning.

Pete

TomS, I have a similar problem posted and have not received any replies. I have noted one specific on my 06 dually that you may want to check on yours. On mine the problem comes and goes with operating temperature. To test this try to shift in and out of Tow/Haul mode when the engine is cold or at least has not run for 4 or 5 hours. Mine works great in this circumstance. Now drive the truck and get it up to normal operating temperature for both the engine and transmission. Now try it. Mine has all kind or problems at this point, only randomly engaging and disengaging after probably 50 pushes of the button on average. Let me know the results if you try this. BTW, mine goes to the Stealer in the morning.

Pete

Mine was kind of reverse of yours. I started out cold and it wouldn't work. I thought it might need to warm up to work properly, but that didn't help either. As soon as I unhooked (after driving 90 miles), I tried it and it worked fine. :confused:

Let me know what the dealer tells you. I've got a good dealer, but I don't think they can help me out if I can't replicate the problem, and they aren't big enough for me to show up with trailer attached! Maybe the trans just doesn't like the trailer......):h

TomS and others interested in Tow/Haul Button problem. Made the trip to the dealer this AM and naturally the problem is gone. Since I thought the problem was temperature related, the dealer suggested that I bring it back after lunch and see if there was a problem in the warmer part of the day. Did this and still no problem, but dealer said they wanted to look at it anyway. Bottom line, they found a software update for the BCM (Body Control Module) that listed several fixes, one being the "Enhancement of the Tow/Haul Button Operation". They installed it and I was on my way. No more problems yet. Time will tell. You might want to get the BCM latest software update and see if it helps your situation. Good luck. BTW, this is my second visit to the dealer for service and I give them an A+ for their service. Purchase price is a whole different subject. Maybe you do get what you pay for ???

Pete

TomS and others interested in Tow/Haul Button problem. Made the trip to the dealer this AM and naturally the problem is gone. Since I thought the problem was temperature related, the dealer suggested that I bring it back after lunch and see if there was a problem in the warmer part of the day. Did this and still no problem, but dealer said they wanted to look at it anyway. Bottom line, they found a software update for the BCM (Body Control Module) that listed several fixes, one being the "Enhancement of the Tow/Haul Button Operation". They installed it and I was on my way. No more problems yet. Time will tell. You might want to get the BCM latest software update and see if it helps your situation. Good luck. BTW, this is my second visit to the dealer for service and I give them an A+ for their service. Purchase price is a whole different subject. Maybe you do get what you pay for ???

Pete

Thanks Pete! As soon as I get back to the US, I'll go to the dealer for the update.