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Should I use Tow/Haul mode everyday?

tflux
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tflux New Member

tflux

Posted
Posted

I read somewhere that Tow/Haul mode is actually easier on the transmission due to less "slippage" during gear shifts. The argument was that the shift will feel more harsh, but there is actually less wear and tear on the transmission.

 

Anybody know if this is true?

 

Should I always use Tow/Haul mode even during "easy" driving?

 

I'm assuming the gas mileage will be a little less due to the increased revving of the motor, but I'm not too worried about that. I don't drive many miles.

 

Thanks!

 

SouthernSilveradoGuy85 Senior Enthusiast

SouthernSilveradoGuy85

Posted
Posted

Not to sound like a smartass (even though I am), but if GM thought it should be in that mode all the time then they wouldn't have it as a mode that you can turn on and off.

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Chevy Joe Enthusiast

Chevy Joe

Posted
Posted

No reason to leave it in tow mode, not sure the higher RPM is "good" for the trans or the engine

All the mode does is change the shift points in the transmission to make the transmission stay in the lower gear for a longer time. For Example (these are made up numbers) with it off your tranmission may shift from 1st to 2nd at 10mph then to 3rd at 25mph then to 4th at 40mph. With it on it would shift from 1st to 2nd at 20mph then to 3rd at 45mph then to 4th at 55mph

tflux New Member

tflux

Posted
  • Author
Posted

All the mode does is change the shift points in the transmission to make the transmission stay in the lower gear for a longer time.

 

I think tow/haul mode does more than this. I think it makes the shift quicker (harder) also.

 

I appreciate the responses. Let me revise my question...

 

I read once that a "smooth" shift (normal mode) puts more wear on the friction material in the transmission. A "hard" shift (tow/haul mode) puts less wear on the friction material in the transmission.

 

Does anybody know if this is true?

SouthernSilveradoGuy85 Senior Enthusiast

SouthernSilveradoGuy85

Posted
Posted

The only time I can see when a harder shift wouldn't hurt as much is at WOT. When I had my 98 Z71 something with the trans went bad and seemed like at least once per day it would shift so hard it would shake the truck. I then had to pull over, cut the truck off for a couple minutes and then it would shift smooth. Eventually the trans finally went completely out.

 

So anyways, with normal driving, especially in town, I can only imagine that harder shifting wouldn't be easier on the trans. The trans will shift harder at WOT to make it smoother. I believe more throttle the more pressure and harder it needs to shift to keep it shifting smooth.

 

Like I said in my first post, if GM thought it would be better to do all that all the time then they wouldn't have it as a mode that you can turn on and off. It should only be on if you're towing a trailer. An empty light trailer you shouldn't have to, but you'll feel it strain so that's when you turn it on.

Chevy Joe Enthusiast

Chevy Joe

Posted
Posted

 

I think tow/haul mode does more than this.

 

 

Then why are you asking here? You should use GOOGLE and search the internet...SMH

 

The info I gave you was from a Certified GM mechanic that works for my local dealer

 

I'm Out...

Chevor Senior Enthusiast

Chevor

Posted
Posted

I use it alot for stop and go traffic.

  • 3 years later...
Aaron Brown New Member

Aaron Brown

Posted
Posted

I use tow/haul mode every time I drive my truck. The fuel mileage loss isn’t that different. And the majority of dealership mechanics are idiots. So I wouldn’t base any decision on their recommendations. Also the fact that it’s not in this mode from the factory indicates, as far as I’m concerned anyway, to use it. The factory clamps every part of our trucks to make them more eco friendly. Tow/haul shifts exactly how I do driving a manual. In normal mode it’s shifting constantly, and doesn’t shift down soon enough on inclines. Manuals last longer because of how you hold the gear longer, so that leads me to believe an automatic would do the same. Just my 2 cents. 

diyer2 Senior Enthusiast

diyer2

Posted
Posted

Tow/Haul mode for towing IMO.

My manual says to use it when,

Tow/Haul is designed to be most effective when the vehicle and trailer combined weight is at least 75 percent of the vehicle's Gross Combined Weight Rating(GCWR). 

Nothing is perfect but I figure the engineers know more than me about the design of my truck.

 

:)

XJ2.5 Enthusiast

XJ2.5

Posted
Posted

As far as I know tow/haul changes the shift points and increases fluid pressure in the transmission. Not sure to what extent it would increase the life of the transmission, but it would definitely reduce slippage. The way GM set these transmissions up from the factory is straight up garbage. They prioritized smooth shifts over longevity, thats why i have a corvette servo and transpo hd2 shift kit in mine. Installing a shift kit will do much more to extend the life of the transmission than leaving it in tow/haul.

Sent from my LM-G710VM using Tapatalk

  • 3 years later...
Armando Guerrero New Member

Armando Guerrero

Posted
Posted

Of course it's great for towing, but I also use it to get a little more performance when I need it. It changes the shift ability of your gears so you can get the most out of all your 8 cylinders,all the time..at the cost of a little fuel economy. It'll stay in the higher end of the lower gears longer than it normally would, so it almost shifts like I would on my bike or in a Manuel trans... No sluggish gear searching. 

It really gives my 02 Silverado 1500 4.8L V8 that pep that I miss from the 02 1500 5.3L V8 I had right before this one... especially when Im going waaay to slow and need to merge with the speed of fast traffic from an on ramp to the freeway 

Autocop Enthusiast

Autocop

Posted
Posted (edited)

Tow/Haul mode performs two primary functions. First, it will cause the gearbox to upshift later and downshift earlier than usual, keeping the engine in its power band. This makes it easier for the vehicle to tow or haul whatever is in the back, albeit at the expense of some fuel economy. On downhills, Tow/Haul mode selects a lower gear for a stronger engine-braking effect. This reduces the demands on the brakes, which reduces the odds of the brake pads or fluid overheating.

Second, the gearbox won’t shift as much as it would regularly, which helps keep transmission temperatures at a safe level. Some Tow/Haul applications even lock out the top gears for similar heat-management reasons.

Edited by Autocop
  • 2 weeks later...
Bad Bowtie2 Enthusiast

Bad Bowtie2

Posted
Posted

Better suggestion is to leave your transmission in "regular drive mode" and have your transmission's fluid flushed every 75K. New fluid is the lifeblood of a transmission. I recommend a bottle of Lucas brand Transmission Conditioner at this time too....

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