When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
This thread documents the conversion of a 2004 Yukon Denali from a 4L65E to a NVG4500.
The transmission fresh off the semi. Factory bellhousing. (AWD tcase in backround)
Current Truck’s Configuration:
408 based LQ4, TBSS intake, Volant box, stock TB and MAF, Efans conversion, NVG4500 4WD (later style), NP261 manual floor shift transfer case, Escalade steering wheel, other misc crap. The exhaust is Kooks headers and link pipe vbanded to a SpinTech 8000 3" dual in dual out muffLer, over the axle, and two Vibrant quiet resonators near the bumper. Rear facing exit.
Overview (Results)
Drives and runs great almost like a stock vehicle. The manual transmission is not as smooth as what you would expect for a soccer mom family hauler. But it is a unique and fun vehicle with good utility and perfect for what I need it for. 20K miles and 2 years of driving on it so far.
PASSED VA STATE INSPECTION 2 TIMES. ZERO QUESTIONS ASKED. One tech just said he had never seen a manual Yukon before and didn't know they made them. LOL. PASSED NOVA EMISSIONS.
Does the transmission fit in the 1500 SUV platform?
Yes. -- no body lift needed to make it work. The NV4500 is not as wide as the 4L65E so no problems there. The stick shifter is taller so the shift tower actually pokes into the cab of the truck. This isn’t a problem for say. It does mean a close fit to the underside of the console if you are keeping the console and doing a remote shifter set up. From bell housing to tranny mount it is the same length. No modifications to the cross member are required.
Transmission installed in vehicle. The bellhousing of the manual tranny comes closer to my headers than the auto did. No fitment problems here.
Rear POV showing tranny fits in tunnel. Cross member and mount have no mods.
Stuff not working anymore.
Power Adjustable Pedals (RPO JF4).
The motor mounted to the brake pedal and the stock plastic clutch pedal ASM interfere. All components removed. Plugged position indicator back in to get rid of BCM error code.
Reverse Tilt Mirrors
The BCM controls the reverse tilt mirrors. The BCM is still looking for the multiple signals of the NSS which I don't have anymore. I can only provide single wire reverse signal now. The BCM doesn't know how to handle that.
Dimmed rear view mirror
Rear mirror dimming is supposed to stop when in reverse. Doesn't anymore.
Tranny temp gauge.
Looking for solutions to use this. It is currently dead.
"Subwoofer"
Relocated this to the back of the vehicle like earlier GMT800 SUVs. Got a new 8" sub and a factory box off ebay.
Some computer or reprogramming functions?
I haven't tested any of these but any reprogramming routine or function that requires the truck to be in PARK might not work anymore since the vehicle always says it is in DRIVE.
High level install details:
Clutch Pedal Switch.
Wiring for this has to be installed. If you still are against wiring in a switch, you MUST, MUST supply 12 volts to the following pin. NOTE THIS DIFFERS FROM SOME OTHER LS1 APPLICATIONS WHERE YOU GROUND THE PIN. If you do not your vehicle will think the clutch is always pushed in and you will not have the correct throttle cracker and throttle follower function. Also the timing might be wrong. Not sure on that part.
Insert a pin into PCM C1 BLUE 80 way connector pin 35. Run this to pin E of the clutch position switch. The F pin of the CPP had to be supplied with IGN 3 power off the BRAKE fuse in the L/H IPP fuse block.
Reprogramming
I ending up keeping the same 2004 OS. I had to swap the engine cal, engine diag, trans cal, and trans diag segments from a 3/4 ton truck of the same year. Before I did that the computer would not respond to the clutch pedal and I had a lot of tuning issues.
AWD to 4WD
When I started this project the tcase couplers to adapt a 149 to a 32 spline tranny output were not on the market anymore. I went with a manual tcase that came with the NVG4500 from the factory. This gives a nice positive shifting feel. Also it forgoes a tcase encoder, switch, and figuring out all the wiring. All you need to do is measure carefully and cut a precise hole in the floor board. Took about 2 hours to do. Then run the linkage from the shifter to the tcase. Very easy to do. It does conflict with the console though. This requires that you modify the shifter handle by welding. Moved it closer to the driver by 2 inches. Had to trim out some of the side of the console.
Console Modification
Removed the six disc CD changer that I never used. Cut out that portion of the console out to accept the factory style truck shifter. A little bit of fiberglass and vinyl wrap and it was done. Routed the shifter up to the console with no modifications.
Dash Modification
A fabbed a quick and dirty bracket and mounted it to the firewall for the clutch. The Yukon did not have the upper mounting stock. It also lacked the mounting position on the booster reinforcement plate. I had to weld nuts on the back of that. I also had to cut down and modify the brake pedal ASM to fit with the stock plastic clutch ASM. I welded it in the height that I preferred (adjustable pedal)
Steering Column.
Took this apart and removed all automatic related parted. Painted a manual column cover (24261713) the correct color with SEM factory color matched paint. Looks factory now. Also installed Escalade wood steering wheel.
Fuel Lines
Factory ones didn't fit the tranny. Ran -6 PTFE fuel lines for evap and fuel.
Driveshafts
Rear shaft was about 2" shorter. Needed a swap to 32 spline shaft.
Front shaft just needed to be 2" longer. Already had right spline count and yoke.
Last edited by 2002_Z28_Six_Speed; 03-11-2019 at 07:53 AM.
Picture shows that the shift tower pokes into the cab. This tranny barely fits in the tunnel.
Example picture showing the welded bracket mounted onto the body with self tapping screws. Can also see where brake pedal is cut off and welded into place.
What do I need to buy?
DORMAN 20732
Small Brake Pedal Pad
SACHS NFW1050
Flywheel
GM 15027983 or Atomic Fabrication Metal bracket.
Clutch Pedal mounting bracket.
SACHS K7033301
CLUTCH KIT, Standard Replacement,clutch disc, pressure plate, throw out bearing, pilot bearing, grease, spline alignment tool.
GM # 24242325
New Master Cylinder that resolved low clutch engagement point issues. Comes with bushing, rod, switch, and MC all already put together. Pre-bled.
SACHS SH6443WB
Slave cylinder with bearing and flexible braided cable. Has bleed valve. Pre-bled.
Spectre Performance 6284 Large Shift Boot 6-3/4 inches x 7-3/4 inches
Aftermarket shift boot.
ACDelco PT1212
Pigtail for clutch switch.
ACDelco 15998496
Bell housing GM Original Equipment Manual Transmission Clutch Housing ….
Bolts for bell housing M12-1.5 by 140 mm, not sure on exact size local hardware store. Need 4. ….
ACDelco 24261713
Cover trim for bell housing
ACDelco PT107
Reverse pigtail for nv4500 GM Original Equipment 2-Way Male Multi-Purpose Pigtail ….
ACDelco 14014559
Reverse switch for nv4500 GM Original Equipment Back-Up Lamp Switch ….
NV4500 4WD
NP261 tcase w/ shifter
Donor GMT800 2500 HD truck with manual. MW3 RPO CODE.
6 bolt transfer case gasket 6-Bolt Transfer Case Adapter Gasket ….
What works with no mods?
Starter.
Crossmember.
Cruise control.
What is left to do?
The low range switch is not currently hooked up.
Hook up cruise interrupt to clutch switch. 10 min job. But I am lazy.
Investigating swapping out the Denali bumpers to metals off road style to add to the aggressive look.
Factory spare tire holder was broken and removed. Not replaced yet.
Last edited by 2002_Z28_Six_Speed; 03-11-2019 at 07:57 AM.
This is awesome! I have actually wanted to do a ZF6 swap in my RCSB since I got it and 2 weeks ago called midwest trans to order one. After talking to them they talked be out of the ZF6 real quick and I have a NV4500 on the way!
One thing I don't think you mentioned was driveability. Would love to hear how it shifts!
Hope to post some videos soon. Today I did a segment swap on the tranny calibration and tranny diagnostics from a same year manual transmission corvette. This allowed me to remove my neutral safety switch entirely. The car now reports it is in drive at all times and still allows me to start the truck while the clutch pedal is pushed in. It would not allow starts in drive with the automatic segments installed. TG for EFILIVE. Going to do some more testing on how to get the BCM to realise I want reverse. Still manually triggering the back up light circuit.
My year model: PCM sends a class 2 data bus request to the BCM. Which was not playing well with my wiring hacks.
Yea the swap is complete itself and everything with the tranny and clutch works. Been around the block a couple of times. All the gears shift great and seems normal. No weird noises of behaviors from the tranny or tcase.
Where I am getting held up is a motor/cam swap at the same time. Need tuner to finish the tuning. I also changed exhaust set ups at the same time and I have it over the axle but not to the back of the suv. im changing from side to rear exit.
Why'd you segment swap a corvette OS? Why not the same year 6.0/NV4500 truck?
Can't find a tune file for a LQ4/NV4500 truck. I found a 4.8L truck tune and swapped that in. About to give up a hire another tuner. Truck idles great when cold. Swings wildly when warmed up and then stalled. Hard to drive it once warm.
Can't find a tune file for a LQ4/NV4500 truck. I found a 4.8L truck tune and swapped that in. About to give up a hire another tuner. Truck idles great when cold. Swings wildly when warmed up and then stalled. Hard to drive it once warm.
I just had Atomic retune my 4.8/NV4500 combo. Truck was a 5 speed to start but with the previous tuner there was a few issues that atomic smoothed out. It drives better than ever gets 2mpg better and his responses are very fast!
03-14-2017, 01:31 PM
The Yukon NVG4500 Manual Transmission Swap Thread
