6L80 in my M998

[Mogman]

Well she in in the bay and on the lift, so the project actually begins, one of the hardest parts I can see so far is removing the muffler, the muffler mount is a PITA to get to, and it looks like I will have to deal with it twice! I just made a deal on a complete GEP turbo 6.5L with only 100 mi since reset and a 2009 date code on the block, but I do not want to fight more than one problem at a time so I am going to install the 6L80 first and then install the 6.5L sometime later, also I want to see what performance changes take place with the stock 6.2L.

 

[Mogman]

Well I hope the new one goes in as easy as the old one came out! believe it or not the transmission jack took that off center load just fine, I have the jack stand reliving to OC load until the wifey can get home and help me get it off of the jack with the skidloader.

I have no plans to install backup lights but it would be just plain crazy not to install a switch kit while the 4 speed shifter is just laying there on the bench, save yourself some money and buy just the bracket kit and a neutral switch, they are the same but the neutral switch is MUCH cheaper.

I have a few days to get the shifter installed as the TCM-2600 controller will not get here until wed. and I want to connect it and power it up to make sure I can talk to the TCM-2600 (from now on referred to as the controller to avoid confusion with the in the transmission TCM)
The controller is programmed with a USB cable and the TCM is programmed with GM LAN (ODB II) cable.
Now to figure out how to remove those dang dowels from the block!

Here is the link for the blackdog reverse light adapter pieces kit.

Reverse Light Kit Adapter Pieces - Black Dog Customs

The adapter pieces to the Reverse Light Switch Kit. Includes: Adaptor Actuator (Paw) Please Note: Reverse Light Kit Switch NOT included in this product. We sell entire Reverse Light Switch Kits for 3-Speed and 4-Speed at these links.

blackdogcustoms.com

 

[Mogman]

Well the controller came in from Zero Gravity and even though the workmanship looks OK the documentation leaves allot to be desired, the only paper documentation was one page with a complete schematic on one side and a as supplied cable pin out on the other.
The size and font make it very hard to make out, there is a downloadable "software guide" which also leaves allot to be desired as it just skims over the items.
There is no documentation on stuff like where the controller can be mounted or its best orientation would be, but I tossed the rats nest on top of the transmission gave it some power and I can talk to the controller and to the TCM.
So I guess we will be depending on the email help which has answered all my questions so far with as little detail as possible like "that should work" and is never signed so you have no idea whom you are talking to.

I will go to the controllers actual manufacture and see if they have some of the info I am looking for, it seems Zero Gravity is just building the harness and tweaking the firmware, the blue screen indicates I am "on line" with the controller.

I also managed to get the dowel pins out of the 6.2L block, man they were in tight, I tried the old grab them with vice grips and twist back and forth, this has usually worked for me in the past but the more I tried to twist the tighter it got so I resorted to the tried and true drilling them to 5/16 then tapping for 3/8-16 and using a piece of all thread and an appropriate 1/2" socket to pull them out.
I had to grind the ends of with a flappy wheel to get through the case hardening before drilling.

 

[Mullaney]

Well the controller came in from Zero Gravity and even though the workmanship looks OK the documentation leaves allot to be desired, the only paper documentation was one page with a complete schematic on one side and a as supplied cable pin out on the other.
The size and font make it very hard to make out, there is a downloadable "software guide" which also leaves allot to be desired as it just skims over the items.
There is no documentation on stuff like where the controller can be mounted or its best orientation would be, but I tossed the rats nest on top of the transmission gave it some power and I can talk to the controller and to the TCM.
So I guess we will be depending on the email help which has answered all my questions so far with as little detail as possible like "that should work" and is never signed so you have no idea whom you are talking to.

I will go to the controllers actual manufacture and see if they have some of the info I am looking for, it seems Zero Gravity is just building the harness and tweaking the firmware, the blue screen indicates I am "on line" with the controller.
View attachment 849739
I also managed to get the dowel pins out of the 6.2L block, man they were in tight, I tried the old grab them with vice grips and twist back and forth, this has usually worked for me in the past but the more I tried to twist the tighter it got so I resorted to the tried and true drilling them to 5/16 then tapping for 3/8-16 and using a piece of all thread and an appropriate 1/2" socket to pull them out.
I had to grind the ends of with a flappy wheel to get through the case hardening before drilling.
View attachment 849740

.
Yeah, sadly Chinlish is hard to interpret...
Used to be Spanglish but the times have changed.

 

[Mogman]

.
Yeah, sadly Chinlish is hard to interpret...
Used to be Spanglish but the times have changed.

I don't think that is the issue, I am pretty sure this is a USA venture only the technical folks have done a poor job as far as documentation.
Being a technical genius does not necessarily translate into being a good technical writer.

 

[mgFray]

I don't think that is the issue, I am pretty sure this is a USA venture only the technical folks have done a poor job as far as documentation.
Being a technical genius does not necessarily translate into being a good technical writer.

Ya pretty typical they just have the engineers write the documentation. So CLEARLY you must have the same knowledge as the people who spec'd or built it.. so you just need a pinout and a basic wiring diagram to remind you how to use it.

I see this all the time, and country of origin doesn't seem to matter, it's always down to how big is the company and did they cheap out on documentation in order to keep the price of whatever it is where they wanted it.

 

[lpcoating]

"Ya pretty typical they just have the engineers write the documentation. So CLEARLY you must have the same knowledge as the people who spec'd or built it.."

That's called the "Curse of Knowledge". We see it in manufacturing sometimes when a highly skilled fabricator or machinist explains something to someone that is not as experienced.

 

[Mogman]

The transmission is in!!
She went in without issue, and as it turns out the 6L80/NP218 is only 7/8" longer than the TH400/NP218 so I will be able to use my factory shafts,, YAY!!!
I reinforced the cross member along the top with a piece of 2X3/8" flat bar, the output yoke is exactly where it was but for 7/8" more rearward..
The modified cross member is not too much different than the 4l80

 

[lpcoating]

As a suggestion, think the flat bar should have at least one gusset? If not two?

 

[mgFray]

The transmission is in!!
She went in without issue, and as it turns out the 6L80/NP218 is only 7/8" longer than the TH400/NP218 so I will be able to use my factory shafts,, YAY!!!
I reinforced the cross member along the top with a piece of 2X3/8" flat bar, the output yoke is exactly where it was but for 7/8" more rearward..View attachment 849947
The modified cross member is not too much different than the 4l80

Wow.. I'm jealous. I'm glad it fit so well.

 

[Mogman]

Wow.. I'm jealous. I'm glad it fit so well.

Actually it is much narrower in the pan area so there is more room to work on either side of the transmission!

 

[Mogman]

I worked out the shift linkage today, the "linkage, bracket" is from a 4l80 and I ended up using a rather short shift arm on the transmission to get the geometry correct, I did have to extend the transfer case shift rod, there was just not quite enough adjustment to make up the difference.


This is what the lever looked like, I had to grind off the back side where it was "bucked" into place to remove the ball, then before I could drill it out to 3/8" I had to get the hole area in the lever cherry hot then let it cool down to room temperature slowly because it was hardened, then heat it back to cherry red and quench it in oil to re-establish the hardness after it was drilled.
The GM part number is 15724078

 

[Mogman]

The 2009 GEP turbo engine with less than 100mi on it arrived in Papalote today, there was some interesting "de-mil" work done to the turbo, seller gave me two uncut turbos in the deal. man look at those up pipes, really clean!!!

 

[Mogman]

I was going to install the drive shafts today but the front shaft had an iffy joint so I ordered new u joints, I was a pretty sure the rear shaft would be able to collapse enough to make up for the 7/8" shorter path between the transfer case and the rear diff. and I was correct, went in no problem.

I also got the exhaust installed which I dreaded as it is a total PITA, unfortunately the crossover pipe and the temperature sending unit I installed on the front of the transmission pan decided to try and occupy the same space and the temp sending unit lost, so I ordered another pan so I can move the bung for the sending unit.

I ordered a Cadillac pan, the main difference is the Cadillac does not have a dip stick, there is a tube in the pan just the right height with a plug on the bottom of the pan, you would start the car and pull the plug and just a trickle of ATF should come out, if not you remove the rubber plug where the dipstick tube would have been and add fluid.

The reason I did this is for two reasons, one is it will always be possible to double check the accuracy of the dipstick, and when I go to the turbo 6.5L the down pipe from the turbo makes for a very convoluted dipstick tube and I may end up abandoning the dipstick all together.

EDIT, I did abandon the dipstick and just use the Cadillac test plug and the rubber plug that replaces the dipstick tube when I installed the turbo GEP engine

 

[Mogman]

Some assumptions are just plain wrong, like thinking putting the temp sending unit in the front of the pan was a good idea.

But adding a temp sending unit to the transfer case was also full of surprises, I have no idea why somebody thought that a plug that screws into an aluminum housing needed to be heat treated but when I tried to drill it it was like trying to drill a diamond, busted out the ol Rose Bud and heated it up to a little beyond cherry red and then let it cool down by itself and it drilled like butter..

Well while I am waiting on a new pan and the u joints I will get started on the wiring...

 

[Mogman]

Managed to get the TPS installed today, another PITA job done!

Once the switch was removed there was a black plastic piece held on the shaft by the same pin as the TPS would be driven by.
I simply went WOT so I had access to where one of the pins was, then I took an old pocket knife and heated it with a torch and literally cut through the plastic piece at the place were the pin went trough, then I took a screw driver and pried the cut, the plastic piece split in half on the other side where the pin was and presto problem solved

 

[Mogman]

I am freaking ecstatic!!! finished with the drive shafts, had to modify the 4L80 shift "slave lever" because of drive shaft clearance issues but after I pored some ATF in the trans. I fired it up and PRESTO it WORKS, so far on the lift anyway, I do not have the tire size/gear ratio programmed yet so the speed is probably only close but she sifts up and down just fine, I think the default for lockup is 50MPH but you can see it is in lockup in the second pic, the first is idling in park.
This is the monitor on the tuning software for the controller.
And no puddles are forming underneath so far YAY!!
The top shift indicator is the lever position the lower one is what gear it is actually in.


I am going to the beach in the DuraVee in the morning, maybe the last day for a while I can enjoy it since it has no doors, maybe when I get back I may take the Detroit out for a test drive!!

 

[Mogman]

MAN, this is a COMPLETELY different animal!!!!!!

from 2900@60MPH to 1800@60MPH, same mechanical tach and same GPS speedometer! I hate that I am going to lose the tach when the turbo GEP goes in but then again you really don't need a tach when you are not on the edge of disaster all the time.

2150@70MPH I could not be more pleased, no more gripping the steering wheel tight in case she blows up!!

I do have some more tuning to do, I need to move the shift points down as I have to lift the throttle to get it to shift but the shift firmness feels about right.

Because of the tuning I cannot give a 0-60 time yet but she feels more perky for sure!

Also much like the DuraVee and its Allison the vehicle moves when put into gear at idle, with the TH-400 you had to give is some gas pedal to get it to move, I always thought the mantra that the HMMWV transmission had a special diesel TC was bull S%it, I suspect it was the same one used in gassers

YAY!!!!!

EDIT, I am having issues programming the TCM, this will get resolved meanwhile I fudged the TPS calibration in the controller and am getting an idea on how great this is, preliminary testing shows 0-60 in less than 20 sec, originally it was 27.4 and it cruises comfortably at 70, of course this is on flat road, the minuscule HP of the 6.2 is still there just not NEARLY as pronounced as with the TH400, BTW that 1800-2200 RPM range will be right up that GEP Turbo's alley!!!

AND of course this is a helmet top loaded with all kinds of stuff including front and rear winches and full off road gear so it is as aerodynamic as a brick and weighs in at over 7400LB

 

[MattNC]

MAN, this is a COMPLETELY different animal!!!!!!

from 2900@60MPH to 1800@60MPH, same mechanical tach and same GPS speedometer! I hate that I am going to lose the tach when the turbo GEP goes in but then again you really don't need a tach when you are not on the edge of disaster all the time.

2150@70MPH I could not be more pleased, no more gripping the steering wheel tight in case she blows up!!

I do have some more tuning to do, I need to move the shift points down as I have to lift the throttle to get it to shift but the shift firmness feels about right.

Because of the tuning I cannot give a 0-60 time yet but she feels more perky for sure!

Also much like the DuraVee and its Allison the vehicle moves when put into gear at idle, with the TH-400 you had to give is some gas pedal to get it to move, I always thought the mantra that the HMMWV transmission had a special diesel TC was bull S%it, I suspect it was the same one used in gassers

YAY!!!!!

EDIT, I am having issues programming the TCM, this will get resolved meanwhile I fudged the TPS calibration in the controller and am getting an idea on how great this is, preliminary testing shows 0-60 in less than 20 sec, originally it was 27.4 and it cruises comfortably at 70, of course this is on flat road, the minuscule HP of the 6.2 is still there just not NEARLY as pronounced as with the TH400, BTW that 1800-2200 RPM range will be right up that GEP Turbo's alley!!!

AND of course this is a helmet top loaded with all kinds of stuff including front and rear winches and full off road gear so it is as aerodynamic as a brick and weighs in at over 7400LB

Congratulations on the great progress!

 

[Mogman]

I went for a 70 mile jog today and after fudging the TPS calibration it shifts pretty damn good, I would like to fine tune it a little but if I cannot I will not be too heart broken,

This conversion was worth every damn penny as far as I am concerned!!

Tooling along at 65-70 MPH I can barely hear the fan when it kicks in and do not have the large loss of power as the engine tries to twist the fan at a bazillion RPM.