Should I Use Tow/Haul mode?

MNDave · March 15, 2012

I am leaving on a 400 mile (one way) trip tomorrow, and I will be pulling a trailer but it will be a fairly light load. Aluminum 6 x 10 trailer with two 4-wheelers and a portable ice house in the bed of the truck.

Should I use my tow/haul mode for that, or would I be better off without it on that size load?

'05 1500 5.3L

Thanks

MikeNH · March 15, 2012

If you find the trans is shifting real often then use it. If it drives normally then keep it off. For what it's worth, I did not use the T/H mode on my 2011 pulling a 6x12 UHaul trailer from NH to MI.

zogg · March 15, 2012

I pull a 5x10 utility trailer with my Escalade loaded with a Kawasaki Mule UTV that weighs about 1,000 pounds. Generally, We are going camping so the back of the vehicle is generally loaded with "stuff". I only had to use Tow Haul mode one time...I had the Mule bed loaded with firewood, and really had it overloaded. I only needed tow haul mode when going up and down hills when the tranny kept shifting its heart out....

Otherwise, I don't even think about it. Realize though, the Escalade has a 6.0L engine vs your 5.3, so there is a small difference in HP and torque...it has a tow rating of 8,000 pounds, and I have never got close to that....

AirForceAngler · March 15, 2012

Why would you not use it? You may see a slight decrease in fuel mileage, but I'd gladly take that versus shortening the life of an expensive transmission. Plus it offers better engine braking if you're going to be in hills.

MikeNH · March 15, 2012

Why would you not use it? You may see a slight decrease in fuel mileage, but I'd gladly take that versus shortening the life of an expensive transmission. Plus it offers better engine braking if you're going to be in hills.

If the trans isn't always shifting or lugging in gear, you aren't shortening the life of anything. I figure at most my setup was 3,500 lbs and all T/H did was keep it in a stupidly low gear when it was not needed. This was with the 6-speed though. the 4L60 may not be as well-mannered. I also downshifted as I felt needed for hills. It was never in any danger. The only time my trans temp was over 200 was when I was stuck in traffic in Cleveland for an hour and then it only hit 205, nothing to worry about. Otherwise, 150-170 degrees for the most part.

AirForceAngler · March 15, 2012

Why would you not use it? You may see a slight decrease in fuel mileage, but I'd gladly take that versus shortening the life of an expensive transmission. Plus it offers better engine braking if you're going to be in hills.

If the trans isn't always shifting or lugging in gear, you aren't shortening the life of anything. I figure at most my setup was 3,500 lbs and all T/H did was keep it in a stupidly low gear when it was not needed. This was with the 6-speed though. the 4L60 may not be as well-mannered. I also downshifted as I felt needed for hills. It was never in any danger. The only time my trans temp was over 200 was when I was stuck in traffic in Cleveland for an hour and then it only hit 205, nothing to worry about. Otherwise, 150-170 degrees for the most part.

T/H mode also increases the pump pressure and allows for quicker/firmer gear changes. This means less slippage of the clutches when shifting while towing. More slippage also means more heat. Heat is the mortal enemy of an automatic trans. Do whatever you want, it's your trans but it's not that hard to push the button.

MikeNH · March 15, 2012

Why would you not use it? You may see a slight decrease in fuel mileage, but I'd gladly take that versus shortening the life of an expensive transmission. Plus it offers better engine braking if you're going to be in hills.

If the trans isn't always shifting or lugging in gear, you aren't shortening the life of anything. I figure at most my setup was 3,500 lbs and all T/H did was keep it in a stupidly low gear when it was not needed. This was with the 6-speed though. the 4L60 may not be as well-mannered. I also downshifted as I felt needed for hills. It was never in any danger. The only time my trans temp was over 200 was when I was stuck in traffic in Cleveland for an hour and then it only hit 205, nothing to worry about. Otherwise, 150-170 degrees for the most part.

T/H mode also increases the pump pressure and allows for quicker/firmer gear changes. This means less slippage of the clutches when shifting while towing. More slippage also means more heat. Heat is the mortal enemy of an automatic trans. Do whatever you want, it's your trans but it's not that hard to push the button.

Excess heat isn't a problem if the trans isn't shifting. Once I got out of the hills in MA and eastern NY the truck pulled 6th 90% of the time. The 6-speed shifts no firmer in T/H in most situations, it doesn't have the night and day difference the 4 speeds have with it. If you actually read what I wrote you'd see I was monitoring trans temp the enitire time to make sure things were okay.

crankman · March 15, 2012

Yes, yes and Yes. Your truck will appreciate it greatly. Think of the tow haul button as a tool provided to help you do your job.

kstruckcountry · March 15, 2012

Start without it, and it you feel like you need it, press the button. MPG loss isn't too bad.

AirForceAngler · March 15, 2012

I really don't understand why someone wouldn't use this item? Is it because it may use a bit of extra gas? A/C uses more fuel to run also. Do you leave it turned off all the time also? It's not "required". I assure you, this system was designed by someone with a lot more automotive engineering experience than 99% of us here. But as I've said before, it's your truck, your transmission and your $$$ that's going to go into fixing the transmission prematurely by not using it as designed.

TimmyG · March 15, 2012

Tow/haul is for hills to keep the truck up and downshifting so much, on flat land its just a waste of gas

MikeNH · March 15, 2012

I really don't understand why someone wouldn't use this item? Is it because it may use a bit of extra gas? A/C uses more fuel to run also. Do you leave it turned off all the time also? It's not "required". I assure you, this system was designed by someone with a lot more automotive engineering experience than 99% of us here. But as I've said before, it's your truck, your transmission and your $$$ that's going to go into fixing the transmission prematurely by not using it as designed.

I've explained myself 2 or 3 times now. Gas use is not a concern whatsoever. I chose not to use it because all it did was keep the trans in 4th or 5th when it ran steadily, WITH NO SHIFTING WHATSOEVER in 6th for the bulk of my trip. There is no reason to have the engine running at 3500 RPM on flat land, you gain nothing other than drowning out the radio. If the truck started not wanting to stay in 6th, I'd switch to M5 or M4 depending on what the situation was. Other than the hour being stuck in traffic, my trans ran at a max of 170 degrees (F). That is normal operating temp and nothing to be concerned about.

It isn't about engineering experience, it's about common sense. I know what conditions pose a risk to the truck and they were not present during my trip. I guarentee you that my transmission will not fail prematurely because I did not use T/H mode. This truck is spec'd to pull 9,600 lbs. I had about a third of that behind me, at most. There was no risk. All T/H would do is make the drive louder and make me stop for gas sooner which wasn't really a concern as I was not paying the fuel bill anyhow.

To the OP-

Use T/H mode if you're at all worried. I chose not to because I know what to look for hazard-wise when towing.

AirForceAngler · March 15, 2012

Tow/haul is for hills to keep the truck up and downshifting so much, on flat land its just a waste of gas

How do you figure it's a waste of gas? Even in T/H mode, on flat land my truck will shift into OD when pulling a lighter load. When I'm pulling a heavier load, I keep it in 3rd, in T/H mode. T/H will not prevent the transmission from shifting into a higher gear if it determines that gear is appropriate.

A few times while towing my travel trailer (5500 lbs in T/H) on flat ground I tried putting the trans in OD. On level ground the truck stayed in OD but my fuel mileage did not increase at all and the trans temps went up. Put it back into 3rd and the mileage remained the same and trans temps went back down.

MikeNH · March 15, 2012

Your trailer is more than 2000 lbs heavier than what I towed. At 5500 lbs I'd probably run T/H too depending on how the truck behaived. My point is just that T/H as a blanket recommendation with any trailer is a bit silly.