Strangeness while towing

Corbu · 05-25-2006, 11:37 AM

Hey all,
Some insight from some of you more experienced haulers out there.

I was towing my travel trailer over the weekend and was coming back and had a bit of strangeness occur.

To start with I have a 05 KC with O/R and Big Tow, the TT is around 5200 lbs. I was driving back everything was, fine I stopped for gas. Resumed driving had the truck in Tow mode in 4th, I hit a short uphill grade and she granny shifted in and out of 4th down to 3rd twice when it did go back in 4th I noticed the RPMs at about a 1000 RPMs higher than what I normally hit when doing 65 mph. Needless to say my gas mileage went from 9.76 or so down to 5.24. I even pulled over, shut the rig down figuring something in trucks computer went haywire and needed to be reset. The last fifty miles of the trip I just nursed her home. I did call the dealership but they said to drive it normally and see if it is still a problem (There is some good advice, if not the least bit useless).

Any thoughts or ideas on what may have happened would be appreciated.

**konigfritz** · 05-25-2006, 11:51 AM

Sounds like it got stuck in 2nd or 3rd. If you drive it without the trailer and it drives fine,may have been a computer glitch, if not it may be something more serious.

Sounds like it could be a sensor either in the gear shift or a tranny sensor. Good luck.

Beach-TJ · 05-25-2006, 01:25 PM

It sounds like the computer decided not to lock up the torque converter. The computer monitors a lot of things to decide to, or not to, lock up the torque converter. Did you notice how your tranny temp was doing?

*TitanFan59* · 05-25-2006, 04:05 PM

How many times did it upshift and downshift (hunting) before it went into the lock mode?

Corbu · 05-26-2006, 06:25 PM

Tranny Temp was normal, for me it generally hangs out half way or so.

Not sure what you mean by lock mode Titranfan59, pretty much it just went up and down twice, and when it was all said and done it shifted into 4th and was running around 3100 rpm or so at 65. I' gonna take the rig out Saturday and see if I can duplicate the problem. My main concern is that I may relocate soon have a long trip planned (2800 miles). thanks for any insight.

Corbu · 05-28-2006, 08:58 AM

Thought of something I may have overlooked so I checked the TT's brakes before I road tested again. I couldn't duplicate the problem, guess I'll chock it up to a ghost in the machine.

keane · 05-29-2006, 06:07 AM

Quote:

Originally Posted by Corbu

Tranny Temp was normal, for me it generally hangs out half way or so.

Not sure what you mean by lock mode Titranfan59, pretty much it just went up and down twice, and when it was all said and done it shifted into 4th and was running around 3100 rpm or so at 65. I' gonna take the rig out Saturday and see if I can duplicate the problem. My main concern is that I may relocate soon have a long trip planned (2800 miles). thanks for any insight.

Pulling my 8000lb TT, I am at about 2200 rpm at 65 in 4th gear. Up an incline I manually shift to 3rd and leave it there and it is around 3300 rpms, but I am normally going slower than 65. I tend to use manual shift when I am in hilly terrain when I am towing.

Corbu · 05-29-2006, 10:15 AM

I'm beginning to think it may have just got stuck in 3rd but cant figure out why it would have done that. what is everyone else's normal tranny temp when towing?

keane · 05-29-2006, 10:45 AM

Mine temp has never moved.

Beach-TJ · 05-30-2006, 10:00 AM

My tranny temp stays the same towing as it is when I'm not towing. Maybe 1/3 of the way up the gauge. I have only had my tranny temp move up any on two occasions, and both times I bumped the selector down into 3rd, she locked up the torque converter and the temp came right back down. Both of those times I was pulling very steep curvy mountain roads at around 35 to 45 mph towing my Jeep, which is about 6K lbs counting the trailer. And both times the temp had barley moved up and was still under ½ way up on the gauge, but I like to keep it as low as possible.

bclemms · 06-12-2006, 12:57 PM

I have had the same problem twice now. The first time I ran the truck nearly 26 hours and 1600 miles without turning the vehicle off for more than gas. I hit a hilly area and it started doing the same thing. The more you drive it the worse it gets until you stop the vehicle, lift the hood and let it cool for about 20 or more minutes.

It happened again this weekend when I drove from Jackson, Ms to St. Louis to pick up a boat. On the way back it started doing it pretty badly in Memphis and I had to stop and grab a bite to eat and let it cool for about 30 minutes. It was the first time I towed anything and the boat is not very big (17.5 foot fiberglass bass boat). Be sure to take it to the dealership and make them mark the problems that way when your warranty runs out you wont be up a creek.

Also after driving for a long time while it is hot my A/C will lock up and you have to run without the A/C for about a half hour before it works again.

Yesterday I took my boat to the river and after I pulled the boat back on the trailer and pulled it out of the water the engine over heated and all my coolant was on the ground. I used bottled water to run throught the engine and cooling it down and once the engine resumed normal temp it started holding water again. I drove the truck home and have used it all day today without major issue. The truck does have a slow leak under the radiator and when I took it to the dealer they wanted $700 for a new radiator plus $270 to install it. I have yet to find an aftermarket radiator.

**HudsonValleyTitan** · 06-17-2006, 08:14 AM

Is it just me? I don't understand the complaint here. I tow a 8k+ TT and it pulls and shifts fine. It knows when to lock up the TC and when not to depending on weight, grade etc. If you're using TOW MODE and keeping it in 4th gear, what's the problem? I'd worry only if the tranny temp started to rise. If to complaint is that it hangs up w/o locking the TC after a climb, just pop it into 5th for a minute when you get to level ground....see if that doesn't help.