Cruise control and tow

[mas360]

A co-worker of mine says that using cruise control while towing a heavy trailer is bad for the transmission due to the continuous throttle adjustment to keep constant speed.

Is this true? does it make sense ?

[DropBusa]

i have no hard data to support, but i dosent sound like a great idea to me.

[LHMissions]

As long as you are on a level surface for many many miles - no mountains, you should be fine. the transmissions - especially the 5R110's are built very tough - using the tow/haul mode helps too and you should not have a problem.

[kinghawg98]

no problem..unless you hit bumpy terrain and the trailer pushes you while the TC is locked up. That is not pleasant and probably not good for the trans.

[dieselcrawler]

I don't see how the cruise would be any diffrent than your foot doing the same job, modulating the throttle to keep your chosen speed... Obviously, within reason, I don't see how it would hurt. I use mine when the situation warrents it, reguardless of load. If I'm towing a heavy load, I'm using the 40hp tow tune on my DP tuner anyway, and on flat, straight roads, cruise works fine. I run the 80hp econo tune most of the time, even towing lighter loads such as quads and camping stuff in a 12' box trailer...

And if you think about it, if you're in adverse conditions, as in hills, turns, bumps, etc, most likely you've hit the brakes and disengaged the cruise anyway!

Just use a little common sence. (And don't make fun of my spelling!)

[tubular031]

I use my cruise when I can. I pull a 12k 5th wheel and if I can hang at 1900 to 2100 rpm (65 to 72 ish) I can use it most of the time. If I come to a big incline or have to slow to less then 65 I can not use it at all with out it hunting in and out of OD. If I am pulling my boat or little cargo trailer I use it pretty much all I can!

I had a load in my little trailer and it was about 7k total including the trailer. I put it in my 70 tow setting and hit the CC at 68 and drove 250 miles home from OKC. never left OD and never screamed in pain like it does pushing 70 up a hill pulling the 5er

[SuperCrutyPS]

I tow a 12K GVW 5th wheel.

As stated above, I pull with Cruise when it's flat or slight ups/downs. If I start getting into hills, I'll tap the brake and take it from there. I have run it on a grade once. It stayed on until the truck dropped below a certain speed, then it disengaged on it's own. Since then, I take over way before that point.

[mas360]

Originally Posted by dieselcrawler

I don't see how the cruise would be any diffrent than your foot doing the same job, modulating the throttle to keep your chosen speed... Obviously, within reason, I don't see how it would hurt. I use mine when the situation warrents it, reguardless of load. If I'm towing a heavy load, I'm using the 40hp tow tune on my DP tuner anyway, and on flat, straight roads, cruise works fine. I run the 80hp econo tune most of the time, even towing lighter loads such as quads and camping stuff in a 12' box trailer...

That's exactly my question. The answer I got is that the cruise is much more sensitive than driver's foot and therefore the transmission constantly changes gear and consequently causes premature wear.

If that is the case, my dad's transmission would have died a long time ago as he is a very nervous driver, he pumps the gas and let go fully and then pump again at the frequency of once every minute.