Tow/haul Button Question

MikeInCtown · May 4, 2009

Yes, I did a search. According to what I have read, the tow button makes the shifts firmer and the rpm range go up for shifting. I have also read that it will unlock the converter faster when needed.

My question is: Will the trans still go in all gears 1-OD plus lockup with the tow button depressed? I loaded up my truck this afternoon and put it in the haul mode and the only thing I noticed was that the trans shifts MUCH firmer than normal. Goes through all gears and runs same RPMs on highway so I'm assuming lockup is functional.

Is there really a reason to using the button if the truck does not seem to struggle with the load? (ie, it's not like it activates more cooling)

thxs

-Mike

MS3DALE · May 4, 2009

Yes, I did a search. According to what I have read, the tow button makes the shifts firmer and the rpm range go up for shifting. I have also read that it will unlock the converter faster when needed.

My question is: Will the trans still go in all gears 1-OD plus lockup with the tow button depressed?

Yes....It will go in all gears plus lockup with the button depressed.

MS3DALE · May 4, 2009

BTW....Did Justin redo your tow/haul mode button for different shifts/torque management settings during the tune meet?

smattei14 · May 4, 2009

Yes, I did a search. According to what I have read, the tow button makes the shifts firmer and the rpm range go up for shifting. I have also read that it will unlock the converter faster when needed.

My question is: Will the trans still go in all gears 1-OD plus lockup with the tow button depressed? I loaded up my truck this afternoon and put it in the haul mode and the only thing I noticed was that the trans shifts MUCH firmer than normal. Goes through all gears and runs same RPMs on highway so I'm assuming lockup is functional.

Is there really a reason to using the button if the truck does not seem to struggle with the load? (ie, it's not like it activates more cooling)

thxs

-Mike

According to GM...you should use it when you have a load that is 75% of your GVW

C & A s Dad · May 4, 2009

+1 on using it only when loaded to 75% or more of your GVW. Holds shifts longer and makes them firmer. Also reduces the amt of "hunting" for gears if you are running in OD.

mr_bots · May 4, 2009

On a different note: did they get rid of the firmer shifting in Tow/Haul on the 900s? Mine shifts the same either way just at a higher rpm. Nothing like the 03 Yukon my parents used to have.

MS3DALE · May 4, 2009

On a different note: did they get rid of the firmer shifting in Tow/Haul on the 900s? Mine shifts the same either way just at a higher rpm. Nothing like the 03 Yukon my parents used to have.

You know what Matt.....Now that you bring that up your right,My '99 and '04 shifted a lot firmer in tow/haul mode then my '07 does.

I thought it was just in my head,Guess not

team3-8 · May 4, 2009

Rich, Justin set mine so in tow/haul mode I have more SPIRITED performance. I did use that term to my wife yesterday when I got home and she asked me how it went. Didn't really want to say "Boy does this fkr go now."

MS3DALE · May 5, 2009

Rich, Justin set mine so in tow/haul mode I have more SPIRITED performance. I did use that term to my wife yesterday when I got home and she asked me how it went. Didn't really want to say "Boy does this fkr go now."

Yeah thats right....The "SPIRITED" performance driving!!

He set mine up that way also

team3-8 · May 5, 2009

That's definitely my description when anyone asks me how's it run now. "Very Spirited" I love it.

chevyjb · May 5, 2009

i have 2009 4speed trans with 4.8 motor when i put in tow haul mode i notice nothing

i am not towing or heave a load i see no dif in rpm also

MikeInCtown · May 5, 2009

BTW....Did Justin redo your tow/haul mode button for different shifts/torque management settings during the tune meet?

I told him that I may actually do some hauling/towing from time to time for friends or whatnot so he left that function alone. I can tell that it shifts at different RPMs and it almost bangs into gear when I get on it. I only had ~500 or so LBS in the back so maybe the normal mode today would have been the best.

He did notice some slippage from first to second that he said was normal for the miles and he changed the line pressure. Boy does it feel great now (normal mode) the trans shifts quickly but not harsh. The engine doesn't dog for that half second during a shift either and it just feels like it wants to keep pulling the entire time I accelerate vs falling on it's face right before every shift.

ColoradoSkiCountry · May 6, 2009

Your turn signal will flash a few more times when you push the lever down slightly (not all the way) without T/H it should flash 3 times, with T/H mine flashes 5 or 6 times. (on the 900s)

InertiaFaze · May 7, 2009

+1 on using it only when loaded to 75% or more of your GVW. Holds shifts longer and makes them firmer. Also reduces the amt of "hunting" for gears if you are running in OD.

Actually the recommendation is to use T/H when loaded to 75% or more of you GCVW rather than GVW. I'm sure you meant GCVW but it's worth pointing out for those who might read your post.