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Discussion Starter · #1 ·
Ive read on other forums (I try to educate myself as much as possible many opinions) and there was a guy that was claiming that he gets better fuel economy when in TH mode empty vs regular mode. I drove into work this morning and in TH mode seemed to shift a bit rougher vs smooth like when I tow. Is it bad to use TH when empty? I caught some real heavy traffic so I can't judge just yet to compare although I will say I didn't need to hit the brakes as hard since tranny was shifting down to assist.
 

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There's no way he got better mpg in t/h
 

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There's no way he got better mpg in t/h
^ He's right, Tow-Haul locks converter in 2nd gear which could help the fuel economy, BUT it also lets the rpm's run higher before a shift. Overall you will DEF get worse fuel mileage in Tow-Haul mode.
 

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Probably not going to see better mileage in T/H but it won't hurt anything to run it if you don't mind how it shifts, I could see it helping some around town by getting the power to the ground more efficiently by locking the TC in 2nd but out on the highway it's not going to make a difference.
 

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Discussion Starter · #5 ·
I don't like how it shifts empty honestly it seems to rough vs empty just wanted to confirm this guy was a nut.
 

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I get better mpg in tow/haul empty without a doubt in my mind! I float around town at 17-2000 rpm and stay in fifth gear at 109 km/h or roughly 65 mph (out of t/h)on the highway.
I do this because I run 35s and a lift and lugging the truck oround at 1300 rpm is no good for fuel mileage at all. It's the luging around that I keep away from this way and 6th on the highway is not bad if i can maintain 130km/h (not going to happen so she stays in fifth unless it's a downhill grade. This yields 18-19mpg highway and 15-16 in town. It isn't no 22 mpg like some claim but I'm extremely happy with that.
 

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Discussion Starter · #8 ·
I get better mpg in tow/haul empty without a doubt in my mind! I float around town at 17-2000 rpm and stay in fifth gear at 109 km/h or roughly 65 mph (out of t/h)on the highway.
I do this because I run 35s and a lift and lugging the truck oround at 1300 rpm is no good for fuel mileage at all. It's the luging around that I keep away from this way and 6th on the highway is not bad if i can maintain 130km/h (not going to happen so she stays in fifth unless it's a downhill grade. This yields 18-19mpg highway and 15-16 in town. It isn't no 22 mpg like some claim but I'm extremely happy with that.
Wouldn't it be better if you controlled the shifting vs keeping it in TH mode? Yes i understand you turn TH mode on and your don't need to worry about shifting.

I guess I never realized the the lugging is bad / fuel suck for the truck. Am I correct to come to this assumption? My truck is stock but I do have a Tonneau cover not sure if that helps or not.
 

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I've did the manual shifting or restricting it to 3rd but it just likes to shift too early and manual is a pain. I find (can also watch it happen on mileage the coach via edge insight) that it takes little to no effort to keep the truck moving at 18-2000 rpm which is exacltly where it shifts in tow haul. keep in mind this is only 30-40 mph I also have 100hp tune which one quick bump on the throttle gets me up to speed and from there it's just Enough throttle to keep the turbo brake from activating. I'm aware that the turbo brake eats fuel but I also use it a lot and basically only use my brakes to stop.
 

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Discussion Starter · #10 ·
I've did the manual shifting or restricting it to 3rd but it just likes to shift too early and manual is a pain. I find (can also watch it happen on mileage the coach via edge insight) that it takes little to no effort to keep the truck moving at 18-2000 rpm which is exacltly where it shifts in tow haul. keep in mind this is only 30-40 mph I also have 100hp tune which one quick bump on the throttle gets me up to speed and from there it's just Enough throttle to keep the turbo brake from activating. I'm aware that the turbo brake eats fuel but I also use it a lot and basically only use my brakes to stop.

Eventually I am going the EFI live route but is the turbo brake really worth it? I read one post guy said wasn't worth it and then others say no diff and yet other say wow dam big diff what's your take?
 

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Discussion Starter · #13 ·
Huge difference, there is no way one wouldn't notice the turbo brake on korys heavy tow tune

When you say Korys heavy tow tune how heavy are you talking about? I'm still looking and trying to figure out who I'm going to have build me or help me with my EFI live when I can finally afford it. I want to get a program that I can run all of the time and not have to worry about damaging the transmission or anything like that and I don't have gauges so I don't want to have to worry about running a real hot tune.
 

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I believe the heavy tow tunes are usually 50-80 extra hp. You should get a egt guage regardless of the tune. An edge cs or cts is a great all in one guage plus it reads and clears codes so it pays for itself after one or two problems it helps you diagnose. Sounds like you might be after a dsp2 switch. Maybe one for good economy and the other for towing. It really just depends on what your doing with the truck.
 

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Eventually I am going the EFI live route but is the turbo brake really worth it? I read one post guy said wasn't worth it and then others say no diff and yet other say wow dam big diff what's your take?
If someone says it isn't worth it or cant tell a diff then they need a prius!! there is a huge diff !! yes definitely worth it!! I have the dsp5 and I have it on 1,2, and 3. Very well worth it!!
 

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3722kevin could easily benefit from using tow haul mode while unloaded. With the added rotating mass, decrease in aerodynamic performance, and higher rolling resistance he needs more power to keep mpgs up. Keeping the converter locked increases efficiency while running fifth gear on 35s really isn't as drastic as a difference as running 32.5s in 6th a some of you are thinking. Lower rpms = lower exhaust pressure = less boost = less air for the intake.
 

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Eventually I am going the EFI live route but is the turbo brake really worth it? I read one post guy said wasn't worth it and then others say no diff and yet other say wow dam big diff what's your take?
Yes they are worth it. Why else would every manufacturer be using them now?
The ones that say no difference are either doing it wrong or its of possibility their tuner didn't tune the cut out point low enough to keep it on in the lower rpms for running it unloaded.
By doing it wrong I mean they may not be using tow haul mode. I personally have no answer to if they are able to use the tow haul mode button as a on/off switch, but engine/turbo breaking is only effective while the converter is locked.
 

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Heavy tow tune is hardly an increase in power compared to other tunes, your talking around 30hp, that is for up to the vehicles gcwr.
yes my heavy tow tune is 30 and light is 60.
3722kevin could easily benefit from using tow haul mode while unloaded. With the added rotating mass, decrease in aerodynamic performance, and higher rolling resistance he needs more power to keep mpgs up. Keeping the converter locked increases efficiency while running fifth gear on 35s really isn't as drastic as a difference as running 32.5s in 6th a some of you are thinking. Lower rpms = lower exhaust pressure = less boost = less air for the intake.
^^ what he said...
Yes they are worth it. Why else would every manufacturer be using them now?
The ones that say no difference are either doing it wrong or its of possibility their tuner didn't tune the cut out point low enough to keep it on in the lower rpms for running it unloaded.
By doing it wrong I mean they may not be using tow haul mode. I personally have no answer to if they are able to use the tow haul mode button as a on/off switch, but engine/turbo breaking is only effective while the converter is locked.
^^ what he said again!! :drink
 
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