Quick Transmission Shifting Question!

[Tylerz71]

Ok, guys, I dont want to sound stupid on this but:

 

If I put my truck (2000 Sierra 5.3 AUTO) into 1st on the column shifter, can I drive it until it revs up and shift up into 2nd, and so on into 3rd?

 

Also, when can I use my tow/haul? In (D) or 3rd?

Will it delay shifts, making the truck quicker?

 

Thanks for any help. I just dont want to mess up my transmission.

[jrrod2004]

It will hold the gears until either you shift it or the truck says "enough"..I tried it on mine and it will shift after reaching about 30 mph without me moving the column shifter from 1st gear

[Tylerz71]

It will hold the gears until either you shift it or the truck says "enough"..I tried it on mine and it will shift after reaching about 30 mph without me moving the column shifter from 1st gear

 

nice. Im gonna try that tomorrow.

 

Now I wonder about the tow/haul mode... I have never even used it and im so temped to push that button.

[johndeeregreen]

Ok, guys, I dont want to sound stupid on this but:

 

If I put my truck (2000 Sierra 5.3 AUTO) into 1st on the column shifter, can I drive it until it revs up and shift up into 2nd, and so on into 3rd?

 

Also, when can I use my tow/haul? In (D) or 3rd?

Will it delay shifts, making the truck quicker?

 

Thanks for any help. I just dont want to mess up my transmission.

 

 

 

 

here is some advice that i hope will help you out first off putting your truck into 1st and then revving it up till it has to shift into second would probably not be a good idea your automatic transmission is best suited to let it shift on its own 1st gear is for when you need some serious engine braking or if you are honestly stuck in some sort form or fashion and as far as im concerned i would probably reccomend using tow haul in D cause it is the final gear in the transmission and by using it in 3rd you wouldnt get the full potential of all the gears possible

 

hope this helps

 

ryan

[jrrod2004]

same thing, by putting the selector in 'D', and then pressing the Tow/Haul button, it will 'hold' the shift points to a higher point in the RPM range, mine shfts at 2500 RPMs or so whenever that button is engaged, that is near the meat of the powerband. Quick question, when did GM get rid of the Red Line on the Tach?? Mine does not have a red area on the tach and I seem to bang the number 6 before I realize the tach is that high

[Tylerz71]

Thanks Ryan.

But what if I shift it when it hits like 4,000 rpm's?

 

And Mike, I dont think my 2000 Sierra has red on the tach, but i may be wrong.

[asilverblazer]

You should not really notice if tow haul is on and the truck is empty, it is much more noticeable when the truck is loaded. It is also better to use 3 instead of D when towing. In fact the tow haul function will eliminate the overdrive electronically until 65mphish or very little engine load exists. The engine and transmission is really protected by all the electronics, you can do quite a bit with that gear shifter and the electronics, will do their best to protect everything.

[VMax2007]

same thing, by putting the selector in 'D', and then pressing the Tow/Haul button, it will 'hold' the shift points to a higher point in the RPM range, mine shfts at 2500 RPMs or so whenever that button is engaged, that is near the meat of the powerband. Quick question, when did GM get rid of the Red Line on the Tach?? Mine does not have a red area on the tach and I seem to bang the number 6 before I realize the tach is that high

 

There is no redline because with DBW, there is no need for it. GM's rev limiter takes care of that for you. 6K is the "Redline".

 

Also, regarding Tow/Haul mode. Yes, it does raise the shift points, BUT it does not change the WOT shift points. So, TH will not help your 0-60 or 1/4 mile times. WOT shift points are set at about 5400 RPMs I believe?. You can change those in a custom tune to as much as 6K RPMs. I had mine changed to 5600 RPMs. That is what Nelson recommended, I really don't care cuz I don't race and never run WOT anyway.

 

The Rev limiter will limit the max RPMs, but GM also has a few "special" rev limiting nannies too. In park or neutral, the rev limiter is 2000 RPMs, and in gear with the brake applied (Powerbraking) it is set at 1500 RPMs.

[dreman]

Go ahead and use Tow/Haul mode. I use it often, even though I rarely tow or haul anything. Watch out for that 1-2 shift, though, because it hits pretty hard at part throttle. Never tried it any other gear than 'D' though.

 

I use it to increase the line pressure to make the trans last a little longer, and raise the shift points. I guess it may have helped, since the truck has the original trans at 280,000 miles.

[ken1mod]

Gentlemen, I will use the tow haul button when I am making a left turn and want the trans to still be in first when I straighten out. It holds first gear to 18mph and when you punch the throttle it takes off like a scared cat. Great fun.

 

Ken

[jrrod2004]

same thing, by putting the selector in 'D', and then pressing the Tow/Haul button, it will 'hold' the shift points to a higher point in the RPM range, mine shfts at 2500 RPMs or so whenever that button is engaged, that is near the meat of the powerband. Quick question, when did GM get rid of the Red Line on the Tach?? Mine does not have a red area on the tach and I seem to bang the number 6 before I realize the tach is that high

 

There is no redline because with DBW, there is no need for it. GM's rev limiter takes care of that for you. 6K is the "Redline".

 

Also, regarding Tow/Haul mode. Yes, it does raise the shift points, BUT it does not change the WOT shift points. So, TH will not help your 0-60 or 1/4 mile times. WOT shift points are set at about 5400 RPMs I believe?. You can change those in a custom tune to as much as 6K RPMs. I had mine changed to 5600 RPMs. That is what Nelson recommended, I really don't care cuz I don't race and never run WOT anyway.

 

The Rev limiter will limit the max RPMs, but GM also has a few "special" rev limiting nannies too. In park or neutral, the rev limiter is 2000 RPMs, and in gear with the brake applied (Powerbraking) it is set at 1500 RPMs.

 

 

Explain a little further on the limiter while in park......does it cut off on yours? Mine does not cut off at all, I can leave it in park and rev that sucker all the way to 6000 RPMs and it will just suck the fuel up and produce more power.....

[VMax2007]

Explain a little further on the limiter while in park......does it cut off on yours? Mine does not cut off at all, I can leave it in park and rev that sucker all the way to 6000 RPMs and it will just suck the fuel up and produce more power.....

 

 

Not on the GMT900's you can't.

 

Mine will because all of those nannies were removed with my tune. Not sure why I would ever need to rev it higher than that in park though? I also can powerbrake above 1500 RPMs if I wanted to, but powerbraking is the worst thing you can do to your tranny (not to mention the rest of your drivetrain).

[jrrod2004]

PTO is the only reason that the truck will ever be revved that high (not all the way to 6000 RPMs)...but that is interesting though. I hope they dont have those nannies on the diesels

[Tylerz71]

Thanks for all the info. I understand it more now.

 

But one more thing;

It will tend to use more gas when in Tow/haul mode, wont it?

 

Im trying what Ken said tomorrow.

[jrrod2004]

it will use a little more, not too noticable, as it will hold the shifts longer and force the engine into the higher powerband range thus sucking more fuel.