Tow Haul Button - does it matter?

[J. Morgan]

Originally Posted by dznf0g

Guys, all of the above could apply. For those of us who are techy types and know/feel their machinery and understand where they are with the robustness of their specs relative to their load can appropriately use or not use the th button. For the rest, leave it on while towing. To give advice otherwise or recommendations to novices wouldn't be prudent and would take a text book and tutoring to learn. Cant be done in a forum post.

This post has it right.

You put that into words exceptionally dznf0g.

[etojeo]

I think you nailed it, tow/haul switch will be left on!

[gypsydad]

I agree...just can't remember where that darn switch is!

[mkcurtiss]

The whole purpose for tow haul mode is to reduce stress on the transmission. The downshifting on downhill grades is a nice extra....
There is no reason not to use it? I get 14 mpg in my Tahoe using tow/haul pulling a 26' ? it is not hurting gas mileage at all, and will absolutely extend the life of the transmission......that is generally a plus, especially for you 10 speed transmission guys.....as I understand it, those transmissions are very difficult to rebuild, and usually are replaced with a new transmission, and they are very expensive.

[dznf0g]

Originally Posted by gypsydad

Your comment above is not true:
Seems the Tow Mode is only needed when towing 10,000# or more
Not accurate in todays vehicles. The computer's in the newer models will control the engine speed and gearing when Tow/Haul mode is selected, regardless of the size load you have. If you think your 2008 is not working properly, it typically can be adjusted. If you read a few threads here on this post, you will note a few folks commenting how it controls shifting and in turn also controlling engine speeds/RPM. I have always found it to be a value with my older Ford vans, 2008 and 2011Tahoe's, my 2012 F150 EB, and now on my F250, where it helps going up and down mountains at highway speeds...especially when towing and using cruise control with my diesel. I use it many times without towing also, going up steep mountains here in Lincoln MT to help keep steady speed without working the transmission shifting. YMMV

He has a 2008. The truck back then lacked a lot of the features of the newer transmissions/electrical architecture. He's right at that 75% bogey, from what he posted...however the proper spec to analyze is GCW, not trailer weight.

Also, he should realize that the 2008 (up to 2019 really) is a relatively primitive, by today's standards, engine and transmission. Bullet proof, bu so "last gen". It's torque curve/trans gearing (6 speed) demand higher RPMs. More info and analysis needed.

[lsbrodsky]

The only thing that bothers me about T/H is that I don't think it ever lets me get into 6th gear(top), at least by looking at rpm when I turn it off or on. I kinda thought that on level 4 lane roads 6th would be just fine, but I have trusted GM engineers to do what is right for the truck and I always use T/H with the AS.
Larry

[dznf0g]

Originally Posted by lsbrodsky

The only thing that bothers me about T/H is that I don't think it ever lets me get into 6th gear(top), at least by looking at rpm when I turn it off or on. I kinda thought that on level 4 lane roads 6th would be just fine, but I have trusted GM engineers to do what is right for the truck and I always use T/H with the AS.
Larry

There is no OD lockout on any generation of GM truck....but conditions can be such that it never gets to a relieved torque load where it wants to be in the next gear. This can happen with any gear depending on conditions, ie. pulling a mountain pass it may stay in 3rd or fourth and "not want to shift. In the case of 6th, it could be something as relatively benign as a strong headwind or side wind. As an experiment, when it stays in 6th, turn around and go the other way. It'll go in 6th.

With my 6.2L 8 speed, it'll sometimes, when conditions are right, it'll stay in 6th and go into 4 cyl mode at about 2200 RPM, and stay there. Instantaneous mileage on the guess-o-meter goes up by 1 to 2 mpg.

It does know best. More so with the newer tech (2020 for HDs)

[lsbrodsky]

Copied this from a forum and it may be the reason I never see 6th in T/H; I never drive over 55 or so.

"how fast are you going? reason i am asking is because it is tough to get into OD in t/h mode. I have to be going around 65 or so. i can be going down the road at 55-MPH in t/h with no load at all on truck and it will not go into OD. as soon as i turn it off it shifts into OD."

Larry

[dznf0g]

Originally Posted by lsbrodsky

Copied this from a forum and it may be the reason I never see 6th in T/H; I never drive over 55 or so.

"how fast are you going? reason i am asking is because it is tough to get into OD in t/h mode. I have to be going around 65 or so. i can be going down the road at 55-MPH in t/h with no load at all on truck and it will not go into OD. as soon as i turn it off it shifts into OD."

Larry

Very probable.

[ktgsmokey]

Towing our new 30' Classic recently, I forgot to engage Tow/Haul and pressed the button after a few miles while at speed. Turns out it does not engage unless pressed at rest and i found the transmission temp overheating after a while. I have a 2015 Ram 2500 MegaCab, so i would recommend definitely engaging Tow/Haul before starting to drive when trailering. Never had the transmission temp send an overheat warning except that time.

[peterp]

Originally Posted by Acheron2010

For me in my gas Silverado 2500, unless I am in the mountains, I leave it off, and enjoy another mile per gallon.

I do the same with my Tundra. For me it's only helpful to keep in the non-overdrive mode when the truck keeps wanting to shift up and down in that confused spot, that and when going downhill it keeps it in 'low' drive for a bit of engine braking (prior to dropping down into 2nd).

[drbrick]

I found out the hard way when driving in the mountains. Stopped for gas and forgot to reengage tow/haul darn near set the brakes on fire going down a steep grade . In tow/haul Red Dragon practically drives itself. Runs cooler, self braking with engine brake, much better performance both acceleration and deacceleration. Just have to remember to turn it on!

[Tireman9]

Originally Posted by dznf0g

Do some research for your brand, but for GM, it not only raises shift points, activates decel down shifting, but also raises line pressure to keep more clutch application force. GM recommends using it when gcw is at or above 75% of rated gcwr.

Good to know. Understandibleanswer.


1. any idea if ford is same?


2. I have a light weight Class-C on Chevy 4500 chassis and am below 75% of GVWR so I don't need to hit the button. Correct?

[dznf0g]

Originally Posted by Tireman9

Good to know. Understandibleanswer.


1. any idea if ford is same?


2. I have a light weight Class-C on Chevy 4500 chassis and am below 75% of GVWR so I don't need to hit the button. Correct?

1) not an expert on Ford.
2) dont have to, but use your discretion on mountain driving. Since you probably would manually select your preferred gear, try hitting the botton and manual. Best to have more line pressure. Maybe experiment with normal driving aat highway speed, after getting to speed and see if it stays in your preferred gear for.that particular geography and wind conditions. IOW, I'd use it whenever it provides your desired driving experience. In your case (below 75% gvw)

[66Overlander]

Originally Posted by ktgsmokey

Towing our new 30' Classic recently, I forgot to engage Tow/Haul and pressed the button after a few miles while at speed. Turns out it does not engage unless pressed at rest and i found the transmission temp overheating after a while. I have a 2015 Ram 2500 MegaCab, so i would recommend definitely engaging Tow/Haul before starting to drive when trailering. Never had the transmission temp send an overheat warning except that time.

On GM trucks you can engage or disengage Tow/Haul at any time and any speed. I can't speak for Ford or Dodge/Ram.

[Atwebs]

If you have “tow haul”; it is an advanced feature...why not use it? Of course a vehicle can tow without it, but what would you gain? It makes towing smoother, easier and for us increases the mileage quite a bit.

[tdmaymac]

I have a 2011 RAM 1500 and have always used the tow haul setting when underway with AS in tow. I find it very helpful in regulating shifting when called for. I’m not aware of other magic it may be performing, but I can quickly tell when I forget to activate it as the RAM just seems happier with it engaged.

[Steven62]

So you are able to tow a 27FB with a RAM 1500?

If I'm going to be on a long flat highway I opt for the mileage and don't engage tow mode. If I'm in the mountains, or stop and go traffic I'll engage it. Towing a 25FB with a RAM 1500.

[mdlemieux]

I have Ford f150 with a 5.6 gas engine and I tow a 22 ft. Bambi Sport. When I first towed the Bambi in January of '18 from point of Purchase in Scottsdale, Az to Groton, NH. I used the tow/haul all the way and lost about 5 mpg and was very surprised when in down shifted drastically when I was going down a steep hill. I had never done much towing and never with a tow/haul option. When I got home to NH I asked my mechanic about it. He said unless you are hauling some real weight, or going up and down in some serious mountainous territory, don't use it. I haven't used it since, have had no problems, and my gas mileage is almost the same as when I'm not towing.

[featherbedder]

Originally Posted by AirstreamJim

I don’t ever exit any vehicle without setting the parking brake. I started doing this a few years back when I read about unexplained roll-away events with Jeep Grand Cherokees, which we also own.

While I’ve certainly owned vehicles in the past that would happily drive off with the parking brake set, none of my current vehicles will do that. The Jeep and the RAM 2500 in particular won’t move an inch with the parking brake set, so there’s no chance of driving off and burning up the brake.

Call it a belt and suspenders approach, but setting the parking brake while hitching up not only prevents that small roll that will screw up your hitch process, but it also adds a layer of security for your helper who may be behind the TV, if somehow the TV pops into reverse (or you somehow didn’t successfully put in Park).

Sorry for the hijack...now, back to the Tow/Haul discussion.

Jim

If you lived in northern states that freeze you would only use park brake one time as it can and will freeze then you are no go, but ok in warm weather. I use tow haul every time hooked to any trailer, trans temp stays cooler plus all things others have posted