Duramax 2001 – 2005 Six Speed Conversion
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Duramax 2001 – 2005 Six Speed Conversion


(guitar riffs) – Hi, I’m Nick with duramaxtuner.com. You know, I kind of get tired of hearing ’06 and newer Duramax owners rag on the older trucks
for a host of issues, most of them can be fixed, but for also being 5-speed trucks. It’s one of the things they
always thumb their nose at the older owners about; they don’t have six gears. At duramaxtuner.com, we
went through the trouble and set a valve body and TCM up to give those ’01-’05 guys 6th gear. Yes, it’s already in the transmission. The gear ratios are there,
the clutches are there, the planets are there. All the hard parts are there for it. GM just didn’t opt for it. So, here we go. TCM valve body upgrade
from duramaxtuner.com is gonna get you that sixth gear. It’s gonna get you that
overdrive from 0.71 in 5th to 0.61 in 6th gear, 15 or 14 percent drop in rpm. Yes, nice for mileage, but also nice for noise, vibration, harshness in the cab on the highway, especially you guys with modified trucks. As we know, when you modify these trucks, usually they don’t get
quieter; they get louder. You put a big exhaust on
it, larger turbocharger, air intake, that sort of thing, the trucks get louder. So what’s nice is we
can cut 350-400 rpm off during cruise. Just keep the truck in its sweet spot. Keep it in that 1750-1850 range instead of humming over
2000 rpm on the highway. To show you what I
mean, let’s take a ride. (rock music) So we’re just jumping
on the toll way here. We’re in a 2005 LLY. It’s got 300,000 miles on it. Just did one of our 5-
to 6-speed conversions, and I have the truck tune set up so it’ll hold 5th gear in tow/haul. And that’s how I’m able
to show you the sound in 5th gear as we get up to speed. And so, this is the
sound you may be used to. This is just cruising
along at 80 miles an hour, let’s say 77. RPMs are 2230, 2250 rpm at 80 miles an hour. And this truck has a
muffled exhaust sound. It’s got a 4-inch muffled kit on it. It’s not a loud truck. It’s got a stock turbo on it. Just a standard 500-horse truck. And all day, right? 2200-2250 rpm. I go to 6th gear. I get 1930 rpm. And that’s 80 miles an hour. So I’m still under 2000 rpm at 80. And the truck just feels like it’s in its happier place. I don’t have to push the throttle as hard. It’s a smoother ride. Soundwise, it’s less. Any time you can cut rpm
off a truck at cruise, your mileage is gonna go up. A mile and a half to the
gallon on the highway is not uncommon, especially
if you’re traveling at high speed. Now any rpm change we quote, that’s different based on rpm, so rpm changes 14 percent. So, the faster you go, the more rpm you’re
gonna cut off your run. Essentially, the faster you drive, the more you need this. The other 6-speed conversions
allow the Edge CTS to correctly read what gear you’re in. With our conversion, CTS
reports the proper gear and torque converter clutch lockup. If you’re interested in a
5- to 6-speed conversion that correctly displays
the gear on the CTS, that allows us to adjust
your shift schedule based on turbocharger size to get the most out of your truck, that runs and shifts and drives great, and will cut rpm and
noise out of your ride, give us a call at duramaxtuner.com. (815) 568-7920. (hard rock music)

About Bill McCormick

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39 thoughts on “Duramax 2001 – 2005 Six Speed Conversion

  1. Wait? So Chevy morons put a transmission with 6th gear but only goes to 5 wow that’s beyond stupid better mpg but didn’t do it wow

  2. not sure where lbz guys get off, have you ever seen a lbz get better mpg than a 5 speed lb7? on highway trips with my 03 its common to see 20-22 if i run at 65

  3. My 2004.5 lly has 172,000 miles would it be worth the $2,000+ add on would I benefit I don’t pull much more like an lawn ornament I get 16.6 mph so far had it a few months now no long trips to see if it gets better mpg would it hurt the tranny to drain the fluid never did this yet

  4. If I were to purchase a new transmission from you all would it already come with this upgrade or is this a separate option on top of the price of a built tranny?

  5. So I have read before that a built trans and 6spd conversion don't go together. Is this the case with this set up? I have contemplated 3.42 gears to be able to have a built trans and lower rpms.

  6. So this is able to be added into a built trans and have the TCM tuned accordingly to the truck build? Unlike the locked suncoast?

  7. Would've been interesting to have this in my 2004.5 LLY. Thought when I got my 2012 Cummins, newer truck, 6 gears, I'd get better mileage. Nope! Worse. Love both trucks though. Cummins has Calibrated Power tunes from these guys with trans tune for about a year now. Works great.

  8. Will this help make the trans last longer than it would without, or just help with mileage and sound?

  9. I would like to buy a 6spd conversion for my 98 Ford Escort, which is currently 5 spd. Do you know if there is availability of the conversion I'm looking for?.

  10. One thing he didn't mention is the price. Why don't they ever tell you how much it wil cost? I don't want to waste my time calling. Just tell me the price and I will decide if it is worth buying. Thanks.

  11. So I recently dropped my transmission to change the torque converter on my built trans and now the dang thing won't shift into reverse and sometimes will shift into drive but drops out after a few seconds. As far as I can tell seems like the trim solenoid F is Shot, that or the wiring. My trans builder is insisting it's the wiring and said he'd send the parts but I'd pay the labor to have some one else redo my shift solenoids and wiring so I decided to order this conversion instead and a new nsbu switch directly from Allison. I have a fleece tap shifter as well. Hoping I might get a call from you guys on Monday so we can discuss further my setup and needs. Hoping this resolves my range shift issues and as far as trouble codes I get a p0743 and sometimes a p0848. You guys are the gurus and I'm tired of getting treated like an after thought by the people who built my transmission. Hope to hear back from guys, you always are so helpful! Thanks in advance!

  12. This is what I need my lb7. The transmission has been going to limp mode. I'm pushing like 400 plus hp with efl live tuner

  13. I have an 02 HD Silverado with the 1000 5 speed. At my mechanics request I recently had my TCM replaced, shortly after I began to have trouble with my shift selector light, the square indicator light that shows which gear you have selected. It comes and goes with no regularity upon start up. Sometimes things work better if you start the truck in neutral. Once it does light there is no problem until you restart the truck. I have had a new shift lever installed along with a new key cylinder, new ignition switch, a new internal trans harness. I trust my mechanic but cannot continue with trial and error. I failed to mention that upon installing the new TCM one of the prongs on the harness misaligned, the vehicle was sent to the dealership to be programed and according to my mechanic no flags were raised. The vehicle did not shift properly and they ended up pulling the TCM out and discovered the problem and reinstalled the TCM. I have been told that the wiring harness that fits into the TCM is very sensitive so I am curious if this is a possibilty or could there be no connection to the shift indicator.

  14. I have a 2001 but I want to put the dash from a 2006 in my truck so I can have the manual shift option with the button on the shifter. "Tap shift"

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