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Tow/Haul mode = Sports mode!!!!

bertiman
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1500fp Enthusiast

1500fp

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I will give this a shot and report back with my findings as well. I typically get 15-18mpg so if there is a noticeable swing i will let you know. It's only gas guys, give it a shot and report back.


I will give this a shot and report back with my findings as well. I typically get 15-18mpg so if there is a noticeable swing i will let you know. It's only gas guys, give it a shot and report back.

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bertiman
bertiman

Why isn't this the default mode for these trucks????? Seems like all good stuff to me:   1) The transmission is more responsive and consistent than in normal mode.   2) Transmission wear is redu

Gmcant33
Gmcant33

So tow haul = win?

TxTruckMan
TxTruckMan

I don't think it changes any of the engine tuning, but only holds gears longer instead of quickly shifting. So it is more sporty, but it will use slightly more gas. Probably nothing very noticeable.

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Justin Nachazel Enthusiast

Justin Nachazel

Posted
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It makes absolutely no sense that you would get BETTER mpg with Tow/Haul - it keeps your RPMs higher and delays up-shifts. By definition, you're burning more gas. Unless something has changed, there is no change to the engine tuning, it only changes shifting.

 

Thats what I was thinking but people are saying they feather the gas to keep it in v4.... not really sure having to feather the gas every acceleration would be worth it. Im excited to see some numbers lol

emeryz28 Enthusiast

emeryz28

Posted
Posted

anyone found any actual downside to this yet? don't care about MPG but meaning extra wear and tear or confusing the ECU by always being in tow haul?

 

 

also what do you guys mean by M6 and M5, you put it in manual and actual shift with the button while driving?

TxTruckMan Senior Enthusiast

TxTruckMan

Posted
Posted

There shouldn't be any downside that I can think of. Even the mileage hit I would expect to be minimal - 0.5 to 1.0 mpg.

gmckenzie Enthusiast

gmckenzie

Posted
Posted

also what do you guys mean by M6 and M5, you put it in manual and actual shift with the button while driving?

 

If you put it in manual mode and M5 it turns off the AFM so you don't go into V4 mode.

 

I find the V4 mode shudders, almost as if I'm lugging the motor, when driving in town. I don't like it so drive in M5 most of the time in the city.

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1500fp Enthusiast

1500fp

Posted
Posted

 

If you put it in manual mode and M5 it turns off the AFM so you don't go into V4 mode.

 

I find the V4 mode shudders, almost as if I'm lugging the motor, when driving in town. I don't like it so drive in M5 most of the time in the city.

Glad i am not the only one who notices the V4 shudders. Must be an "issue" on all of them.

Justin Nachazel Enthusiast

Justin Nachazel

Posted
Posted

Hm the only think I notice really is my truck has a super hard time shifting. I have a 3" lift on it and I didn't drop the drive shaft. Do you think that could be the culprit?

bertiman Enthusiast

bertiman

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I see how it could help mileage in town but on the freeway I shift out of tow haul. Otherwise it doesn't shift in to overdrive.

 

 

Overdrive works in tow mode on my 2015 5.3L 6spd....

Haus_Z71 Enthusiast

Haus_Z71

Posted
Posted

I had blackbear modify my tow haul to make it sport. It was awesome!

 

I'd like to know the details on this. So they modified your tow haul mode how? Is it still optimized for towing?

How is your tune for regular drive then?

My tune is in progress with Blackbear so id like to consider this.

Justin Nachazel Enthusiast

Justin Nachazel

Posted
Posted

Ok ladies and gentleman,

 

I decided to run 3 tests to get some actual numbers. Take them for what you will and know that I drive like a grandma and worked with what I have.

 

Specs:

- 2015 Chevy Silverado LTZ 4x4

- 3" leveling lift

- Airdam still on

- RetraxOne Tonneau cover

- Stock 20" rims and tires

- DeeZee step bars

- Running in 2WD mode

 

Distance:

- 10 miles exact

 

Terrain:

- City stop and go with occasional long stretch all flat land

 

Weather:

- Cloudy and 64 degrees F

 

Location:

Camarillo, CA

 

Assessment with Tow/Haul ON:

- While driving with this on for the 10 mile distance I was able to achieve 15.2mpg during which time I noticed that the RPMs consistently stayed high. Shift points seem to be smoother but at the same time the truck was staying in the same gear for longer before shifting. The hard shifting that normally ensues with my truck went away. The truck DEFINITELY has more sport to it. From a dead stop there is no delay and the throttle is more responsive and more aggressive.

 

Assessment with Tow/Haul OFF:

- While driving with this on for the 10 mile distance I was able to achieve 19.7mpg during which time I noted normal shift points. The shifting is definitely more rough but the rpms constantly stayed down keeping the truck in a higher gear. There is definite difference between having Tow/Haul engaged and not having it engaged when it comes to throttle responsiveness.

 

Selective Tow/Haul Engagement:

- As I was reading through the comments I noted some people saying that the truck remains in gears longer and stays in V4 mode longer. I got to thinking about that and decided to try one more experiment with selectively engaging the Tow/Haul button when in v4 mode to keep the truck there longer. This actually yielded some surprising results. Driving the 10 mile stretch while engaging the button each time my truck entered v4 mode yielded 21.7mpg! Granted, engaging it each time and disengaging it when v8 came on was kind of a pain, but an argument can be made for long distance driving where v4 engages more often and for longer periods. On the freeway my truck stays in v4 most of the time at 70mph but kicks into v8 when a slight hill comes up. If the truck could be forced to stay into v4 during these transitions to small hills, there might be quite a significant increase in mpg.

 

This is just a rough test and I actually plan on doing a freeway test today if I end up going back out. The test will be a 20 mile approx test but I will have more exact numbers when I do it. Let me know if anyone else attempts this or tries this out on the freeway.

 

The truck:

post-149253-0-80348100-1451932388_thumb.png

post-149253-0-80348100-1451932388_thumb.png

post-149253-0-80348100-1451932388_thumb.png

emeryz28 Enthusiast

emeryz28

Posted
Posted

If you put it in manual mode and M5 it turns off the AFM so you don't go into V4 mode.

 

I find the V4 mode shudders, almost as if I'm lugging the motor, when driving in town. I don't like it so drive in M5 most of the time in the city.

 

 

wait so you are saying I can put it in M5 and drive around and it will shift up through the gears normally but stay out of V4? It won't just stay in 5th? or do you need to shift your way up to 5th with the buttons?

fondupot Senior Enthusiast

fondupot

Posted
Posted

 

wait so you are saying I can put it in M5 and drive around and it will shift up through the gears normally but stay out of V4? It won't just stay in 5th? or do you need to shift your way up to 5th with the buttons?

Set it and forget it. Shift to M, click up to 5 and it will shift like an automatic until you shift out of M.

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