Your truck’s transmission takes on a lot of loads when you are towing. Protecting it with necessary routine maintenance and smart driving habits helps prevent costly repairs and improves performance. Especially when you are pulling a heavy load, like a large travel trailer or fifth wheel.
One of the ways truck manufacturers help make the most out of your truck’s transmission, and help with handling when towing under load is with a special feature known as tow haul mode.
If you’re not familiar with tow-haul mode, this article can help you better understand when and how to use tow-haul Button on your truck. This will go a long way toward protecting your truck’s transmission and keeping you off the hard shoulder in the middle of a great vacation.
What Is Tow Haul Mode?
Tow haul mode is a special feature engineered into the transmission drive train of most modern pickup trucks with a towing package installed. It is designed to help your truck efficiently manage heavier towing sessions safely.
Tow haul mode also helps protects your transmission by adjusting the transmission shift patterns, when under load. This effectively reduces the number of shift cycles to ease the transition between gears. Each truck manufacturer engineers its tow-haul mode a little differently to optimize the performance of the specific type of transmission.
How Does the Tow/Haul Button Work?
The Tow/Haul button in the cab of your truck tells the internal computer to activate or deactivate tow/haul mode. When you press the button, an indicator should light up on your instrument panel to confirm that it has been activated. A lot of domestic pickup trucks also have an indicator on the shift lever that glows when the tow/haul mode is turned on.
When you want to turn the Tow/Haul mode off, you just need to press the button again and the indicator stops glowing. Ideally, you want to engage and disengage Tow/Haul mode when the truck is at a complete stop, and give the computer a few minutes.
You need to select it for the truck to know it is towing. Even the most advanced pickup truck won’t simply detect the heavier load of a trailer being connected.
What Is The Tow/Haul Button On Your Truck Used For?
When it’s engaged tow and haul mode directs the vehicle’s transmission to essential shift gears and higher shift points in the RPMs. This improves how the truck or SUV pulls the load, while also preventing the transmission from shifting erratically.
Not only does this help the truck’s overall towing performance, but it can also go a long way toward protecting your gear. Not to mention taking the stress off your truck’s torque converter, which is one of the primary causes of transmission overheating.
Tow/Haul mode is particularly handy if you are driving in a hilly area. While it might feel like it’s shifting a little later while going uphill, the gearing is designed for a smoother gear change and less stress when the transmission does change up to a higher gear.
Then it helps again going downhill to reduce speed and minimize the stress on your truck’s brakes. This is especially handy if your rig doesn’t have an electronic braking assist.
The Disadvantages Of Using Tow Haul Mode
The biggest disadvantage of the tow-haul mode is that it uses more fuel, as the engine tends to run at higher RPMs to ease the shifting dynamics between gears. This is compounded by the fact that your vehicle will naturally burn through 15 to 25% more fuel when towing a medium to heavy load.
One of the other minor disadvantages of the tow-haul mode is that you lose a lot of immediate acceleration through the gears. This shows up most when you are trying to merge into traffic at highway speed.
Tow haul mode can also make it feel like your truck or SUV is bogging down slightly if you need to accelerate up a hill from a stop.
It’s not that the engine is struggling, but that the RPMs are running higher before shifting, which reduces the low-end torque the transmission uses to put the power down over the course of a long climb.
This is something you won’t notice in first gear, but the slow change up to second will leave your truck feeling a little gutless on a long, steep hill.
However, this is more of a perception thing. If the transmission were allowed to change up too early in the gear progression you could actually damage the second gear or stress the automatic clutch.
When Should I Use the Tow Haul Button?
Tow haul modes are meant to be used when you are towing a medium or heavy load. Though it can also come in handy if you need to pull a light load in a hilly area. If you are pulling less than 50% of the truck’s maximum towing capacity on level roads in good conditions, you don’t need to use tow-haul mode. Tow haul modes are meant for times when you need more pulling, braking, or steering force to compensate for a heavy trailer or load.
How Does the Tow/Haul Mode Enhance Safety?
Tow haul mode enhances safety in a few different ways. Right off the bat, shifting at higher RPMs reduces the erratic hard shifts that can damage a transmission. It’s especially helpful if you are towing on roads where the elevation of the surrounding terrain is changing frequently.
Tow haul mode also helps keep the transmission cooler, thus reducing the risk of overheating and/or breaking down the transmission fluid.
However, the higher RPMs of the engine might cause excess heat to build up in the engine bay. So, you should keep an eye on your truck’s temperature gauge when towing.
Tow haul mode is also helpful in hilly terrain. When you are climbing a long hill the higher RPMs before shifting reduce the stress on the transition to shifting up. This will go a long way toward keeping second gear in good working condition.
Then when you descend the hill your transmission downshifts a little bit earlier than you might expect.
This effectively slows down your truck as it descends the slope, thus taking the excess strain off your brakes, and preserving normal handling.
Frequently Asked Questions
Should I Use Tow Haul Mode on the Highway?
If you are towing a medium or light load on a highway with reasonably level roads, you don’t have to use tow-haul mode. Deactivating the tow-haul will even improve your fuel economy on the highway.
However, if the highway is in a particularly hilly area with frequent elevation changes, or you are on a state highway that has occasional stoplights, it might be better to keep the truck in tow-haul mode. This will help to reduce erratic hard shifting and the risk of gradually overheating the transmission.
Can You Engage Tow/Haul Mode While Driving?
You can engage and disengage in tow-haul mode while you are underway. Though the response time in the change can vary depending on the truck and the way tow-haul mode is handled by the internal computer.
Ideally, you want to engage tow-haul mode when you are at a dead stop. Though it’s not dangerous to change tow-haul mode while you are simply driving down an open stretch of level road.
How Fast Can You Drive InTow Haul Mode?
You can drive at the normally posted speed limit when tow-haul modes are engaged. Safety first is critical anytime you are towing. This means you need to stick to the speed limit when you are keeping your rig in the slow/driving lane is ideal anytime you are towing.
Especially since you sacrifice some of your low-end acceleration, which makes it difficult to rapidly accelerate for doing things like passing or overtaking another vehicle.
Should I Drive With Tow/Haul On?
If you aren’t pulling a trailer, you shouldn’t use Tow/Haul mode. It is only meant to help the transmission and truck’s handling performance when towing. While it won’t hurt your truck if you accidentally press the Tow/Haul button while driving, you will nonetheless suffer poor fuel efficiency.
Does Tow/Haul Make A Truck Faster?
Some pickup trucks will have a little extra boost of torque when they first start out with Tow/Haul mode engaged. In that light, it does add some early acceleration.
However, this is compensated later by the fact that Tow/Haul causes the truck to change up to a higher gear at a higher RPM. So, while you might get an early boost of acceleration, there is no net gain in overall speed over time.
Using The Tow Haul Button When Pulling An RV
The tow-haul mode is a convenient safety and performance feature engineered into most modern-day trucks and SUVs with a tow package. When you press the button in your cab, it tells the vehicle’s internal computer to adjust the shifting dynamics.
This caused the truck to shift gradually at a higher RPM range than normal. This serves to reduce the strain and heat buildup on your truck or SUV’s transmission. Though the trade-off here is that you will go through more fuel.
You don’t always have to use tow-haul mode when you are towing. It’s meant more for when you are towing a medium to heavy load, or you need to tackle frequent changes in elevation without the risk of overheating or overstressing the transmission.
If you are just driving down a level highway with a medium to light load, you can deactivate tow-haul mode for slightly better fuel efficiency.
You can safely activate or deactivate tow-haul mode while you are underway, though there might be some lag, and it’s best to make these changes when you are at a dead stop or just setting off.
