thinking about zf6 dmax

jon5212

New member
Oct 13, 2010
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It took me a while to find mine... I probably won't give it up since they are decently hard to find.
 

duratothemax

<--- slippery roads
Aug 28, 2006
7,139
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Wyoming
6od where I can cruise at 60mph turning 1450-1500 rpm

Sorry, but you are exaggerating A LITTLE BIT... :rolleyes:

The allison 5th gear is taller than the ZF 6th gear (.71 vs .74, which is probably one reason why the ZF guys think their truck 'pulls better in overdrive than an allison'), and there is no way in hell my 5 speed allison runs 1450-1500rpm at 60mph. That rpm (1450-1600rpm at 60mph) is like 6-speed allison RPM range...and 6th gear on a 6-speed allison is .61.

That being said, I did grin and have a blast the first time I drove one. But daily driving, hell no...not for me where I live. Especially towing trailers, with all the around-town driving and traffic. And if you shift an allison manually (with the tech 2, so it will stay in X gear and not downshift even if you floor it, and you can upshift as early as you want) with the converter locked, the allison feels no less "directly coupled" as a ZF. The physical power transfer/feel is identical.

Ben
 

lddrew

shootin for 13's
Jan 10, 2011
216
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West Georgia
Sorry, but you are exaggerating A LITTLE BIT... :rolleyes:

The allison 5th gear is taller than the ZF 6th gear (.71 vs .74, which is probably one reason why the ZF guys think their truck 'pulls better in overdrive than an allison'), and there is no way in hell my 5 speed allison runs 1450-1500rpm at 60mph. That rpm (1450-1600rpm at 60mph) is like 6-speed allison RPM range...and 6th gear on a 6-speed allison is .61.

Ben

what ben said, i was scratching my head at that post. i feel like the ZF needs another gear before I would be interested due to my high amount of time spent at 75mph or over.

6spd ally does wonders at these speeds. the ZF6 would be turning way to many rpm's for me to be happy with it
 

mckey73

Ethanol suks make whiskey
Feb 14, 2007
34
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what ben said, i was scratching my head at that post. i feel like the ZF needs another gear before I would be interested due to my high amount of time spent at 75mph or over.

6spd ally does wonders at these speeds. the ZF6 would be turning way to many rpm's for me to be happy with it

Gears are easy to change, tire sizes are even easier. When I put on 315's I went from 19-20mpg to 21-22 and my cruising rpm's dropped more than I expected. Lately I have really considered putting in 4:10 gears, until I look at prices. :cry:
 

x MadMAX DIESEL

<<<< No Horsepower
Dec 30, 2008
7,535
1
38
34
Lexington, Ky
Sorry, but you are exaggerating A LITTLE BIT... :rolleyes:

The allison 5th gear is taller than the ZF 6th gear (.71 vs .74, which is probably one reason why the ZF guys think their truck 'pulls better in overdrive than an allison'), and there is no way in hell my 5 speed allison runs 1450-1500rpm at 60mph. That rpm (1450-1600rpm at 60mph) is like 6-speed allison RPM range...and 6th gear on a 6-speed allison is .61.

That being said, I did grin and have a blast the first time I drove one. But daily driving, hell no...not for me where I live. Especially towing trailers, with all the around-town driving and traffic. And if you shift an allison manually (with the tech 2, so it will stay in X gear and not downshift even if you floor it, and you can upshift as early as you want) with the converter locked, the allison feels no less "directly coupled" as a ZF. The physical power transfer/feel is identical.

Ben

Wonder why mine doesn't work with the dvt in live? Try and start out in high gear and it doesn't something weird.. like limps or just pops to neutral

Shift range inhibited iirc

Sent from my PC36100 using Tapatalk
 
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Chevy1925

don't know sh!t about IFS
Staff member
Oct 21, 2009
21,648
5,795
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Phoenix Az
Sorry, but you are exaggerating A LITTLE BIT... :rolleyes:

The allison 5th gear is taller than the ZF 6th gear (.71 vs .74, which is probably one reason why the ZF guys think their truck 'pulls better in overdrive than an allison'), and there is no way in hell my 5 speed allison runs 1450-1500rpm at 60mph. That rpm (1450-1600rpm at 60mph) is like 6-speed allison RPM range...and 6th gear on a 6-speed allison is .61.

That being said, I did grin and have a blast the first time I drove one. But daily driving, hell no...not for me where I live. Especially towing trailers, with all the around-town driving and traffic. And if you shift an allison manually (with the tech 2, so it will stay in X gear and not downshift even if you floor it, and you can upshift as early as you want) with the converter locked, the allison feels no less "directly coupled" as a ZF. The physical power transfer/feel is identical.

Ben

he has 35s which is the reason for the low rpms

o2greysixer, all the HD trucks, ford 2500-3500, and dodge 2500-3500 have a granny first in their manual trans. they came with either a ZF5, ZF6, NV4500, NV5600, or G5600. And your 6th speed isnt a double overdrive, 5th gear is 1:1 ratio, like 4th is most other manual 5 speed transmissions


i drove my buddies 6 speed cummins around this past week as i worked on it. i hated the 1000 rpm power band it had but it reaaaaally made me want a 6 speed dmax now. ive always wanted one since they first came out but i wont sell my truck for one and the GF wont drive a truck stick :D. guess ill keep on dreamin
 

02greysixer

Active member
Jun 4, 2011
1,829
7
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North Central FL
I know my trans is not a double overdrive like the six speed Allison's. And I know first is granny gear. I never said otherwise. I believe first is in the neighborhood of 5.2:1 or something. I don't ever use it, always start out in second or third. As far as the rpms, I am not exaggerating at all. I will take a pic to prove it when I head to town. My speedo is accurate to within 1 or 2 mph (checked by gps) and my rpms are just shy of 1500 rpm at 60 mph. I am going around 80 mph before my rpms break the 2000 mark. I have 35s and 3.73 gears


Sint frum tha orijinul smert fone
 

Chevy1925

don't know sh!t about IFS
Staff member
Oct 21, 2009
21,648
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113
Phoenix Az
I know my trans is not a double overdrive like the six speed Allison's. And I know first is granny gear. I never said otherwise. I believe first is in the neighborhood of 5.2:1 or something. I don't ever use it, always start out in second or third. As far as the rpms, I am not exaggerating at all. I will take a pic to prove it when I head to town. My speedo is accurate to within 1 or 2 mph (checked by gps) and my rpms are just shy of 1500 rpm at 60 mph. I am going around 80 mph before my rpms break the 2000 mark. I have 35s and 3.73 gears


Sint frum tha orijinul smert fone

im only giving you a bit of back history. chill there speed shifter :D :hug:.
 

kivetts04dmax

New member
May 20, 2010
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Boonville, MO/Pendleton, CA
Gears are easy to change, tire sizes are even easier. When I put on 315's I went from 19-20mpg to 21-22 and my cruising rpm's dropped more than I expected. Lately I have really considered putting in 4:10 gears, until I look at prices. :cry:

how does bigger tires help mpg? Im just curious, I just installed a 6" lift and 35s and it seems sluggish, going to lower lift to 4" and possibly go with 305/55/20 or 295/60/20s..
 

TeaBagger2006

Im a Garrett Nut Swinger
May 11, 2008
3,123
15
38
Bis ND
They help if you're going downhill with a tailwind . With my 37's and stock gearing I hit 2k when I'm at 90 in 6th gear. I need gears:(
 

duratothemax

<--- slippery roads
Aug 28, 2006
7,139
10
0
Wyoming
Wonder why mine doesn't work with the dvt in live? Try and start out in high gear and it doesn't something weird.. like limps or just pops to neutral

Thats the difference between a $4,000 Tech 2 that was designed by the actual people who built the software/ECM's in the first place (GM) and a $799 EFILive.

Im not knocking EFILive, and I NEVER will. But for somethings, you NEED a Tech 2, because nothing else will actually work "properly", even though it might say its working properly.

Perfect example is in some of the DVT's, such as resetting TAPS, Allison fast learn, injector control, and all of the other bi-directional features that handheld tuners have. With a Tech 2, you are guaranteed that the command was executed 100% accurately, properly, and completely. With anything else, it only "sometimes" works, and sometimes doesnt. Ive done experiments with resetting TAPS with a Tech 2 and EFILive, and the end result is completely different.

Like I said, Ross and Paul are incredibly smart guys, the fact that they have 99% successfully reverse engineered what GM has hundreds of engineers and millions of dollars into, is nothing short of awe-inspiring...I dont think people really appreciate how sharp they are. BUT there is still sometimes/some instances where that (sometimes very important) 1% that gets lost in translation, or lost in the reverse engineering process...which is why I will never get rid of my Tech 2, and why I always use my Tech 2 for duramax/allison bi-directional controls and TAPS/fast learn procedures...

Sorry....totally off topic post.

Ben
 

duratothemax

<--- slippery roads
Aug 28, 2006
7,139
10
0
Wyoming
I know my trans is not a double overdrive like the six speed Allison's. And I know first is granny gear. I never said otherwise. I believe first is in the neighborhood of 5.2:1 or something. I don't ever use it, always start out in second or third. As far as the rpms, I am not exaggerating at all. I will take a pic to prove it when I head to town. My speedo is accurate to within 1 or 2 mph (checked by gps) and my rpms are just shy of 1500 rpm at 60 mph. I am going around 80 mph before my rpms break the 2000 mark. I have 35s and 3.73 gears


Sint frum tha orijinul smert fone

I know im splitting hairs, but think your tach might be off...80mph, 3.73 gears, 35" tires, .74 6th gear is around 2150...and thats provided your tires actually measure to a TRUE 35". (which 315's dont).

Regardless, even a 5-speed allison will still have a lower cruising RPM than a ZF6.