Shop Truck build

clinebarger

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Fort Worth, Texas
Driveshaft is built & installed.

New Radiator with Oil Cooler, This truck originally had the light duty (narrow) radiator. A HD (wide) radiator bolts right in.....Just had to use a matching fan shroud.
Installed a factory ('99-'06) Auxiliary Trans Cooler. Had a cooler line set to match. Basically the front section is GMT800/4L60E.....And the rear section is K2xx/6L90E. Cut off all the factory crimps & married the 2 together using Trans Oil Cooler Hose & ear clamps.

Wired the A/C Compressor controls a little different than factory.....
Installed a High Pressure cut-out switch in place of the K2xx pressure transducer, Wired the High Pressure & Low Pressure Switch in series to the ground side of a relay coil, Power side of the relay coil is controlled by the A/C Request signal from the control head.

Started marrying the K2xx engine harness to the GMT800 fuse box & body harness, Not difficult just tedious & time consuming. Had to crimp new terminals on all the Ignition Hot circuits to fit the GMT800 fuse box connector.

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clinebarger

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It's ALIVE!!......Got all the electrical right the first time.

Punch out list.....
*Set the Fuel Pressure, It's making 49 psi at the moment....Enough to start & idle. Needs 58 psi.
*Modify the fuse box cover a little to clear the extra loom.
*Vacuum & charge the A/C.

I haven't tuned a lot of E78 ECM's for swaps, I just simply disabled VATS Patches 1&2, Wrote the calibration & got a crank-no start. No Injector Pulse & no Spark.
Then I remembered the Starter Diag needs to be disabled because there's no BCM to enable the starter over CAN, There are 2 places in the file where it needs disabled. Wrote the calibration again......Still no start.
**There are times when you need to write the entire ECM for some changes to "take", I prefer to NOT do this as the chances of "bricking" the module go up exponentially. But my back was against the wall with this ECM.
Flashing/Writing the entire file took 8 minutes which is an eternity as Flashing modules go.....But it took & the engine roared to life.

Adjusted the calibration for the new tire height & final drive ratio.

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Joined
Dec 7, 2012
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WNY
It's ALIVE!!......Got all the electrical right the first time.

Punch out list.....
*Set the Fuel Pressure, It's making 49 psi at the moment....Enough to start & idle. Needs 58 psi.
*Modify the fuse box cover a little to clear the extra loom.
*Vacuum & charge the A/C.

I haven't tuned a lot of E78 ECM's for swaps, I just simply disabled VATS Patches 1&2, Wrote the calibration & got a crank-no start. No Injector Pulse & no Spark.
Then I remembered the Starter Diag needs to be disabled because there's no BCM to enable the starter over CAN, There are 2 places in the file where it needs disabled. Wrote the calibration again......Still no start.
**There are times when you need to write the entire ECM for some changes to "take", I prefer to NOT do this as the chances of "bricking" the module go up exponentially. But my back was against the wall with this ECM.
Flashing/Writing the entire file took 8 minutes which is an eternity as Flashing modules go.....But it took & the engine roared to life.

Adjusted the calibration for the new tire height & final drive ratio.
Awesome work! And I agree, 8 minutes seems forever.

I found some other things that "live" in the back of a calibration. When I segment swapped the cal on my originally 5.3 equipped Tahoe with that of a 4.8, I kept getting O2 heater resistance codes. Looked up a 4.8 vs 5.3 truck and found they have different part number O2s. Could not find anywhere in HPT to adjust voltages or anything so I ended up taking the stock 5.3 file and just copying parameters from the 4.8 cal over and, Wrote Entire. CEL codes for heaters gone.
 

clinebarger

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Awesome work! And I agree, 8 minutes seems forever.

I found some other things that "live" in the back of a calibration. When I segment swapped the cal on my originally 5.3 equipped Tahoe with that of a 4.8, I kept getting O2 heater resistance codes. Looked up a 4.8 vs 5.3 truck and found they have different part number O2s. Could not find anywhere in HPT to adjust voltages or anything so I ended up taking the stock 5.3 file and just copying parameters from the 4.8 cal over and, Wrote Entire. CEL codes for heaters gone.

Interesting.....I haven't had that issue with P59 controllers, Especially if both files had the same OS?

The only narrow band GM 4-wire sensors that don't swap are Case Grounded Sensors & Isolated Grounded Sensors, GM liked to do some goofy stuff in the early 2000's with the P01 controllers.....Some trucks have Isolated Sensors, Some Case Grounded Sensors......And some had 2 of each. But I haven't seen case grounded sensors on anything newer than 2002.

When I say swap.....You can change the connector & the O2 will function the same.
 

clinebarger

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Thinking of doing a E38 ECM swap.....Can't seem to get analog Vehicle Speed or Tach outputs on the E78. Should've done a little more research before licensing the E78.

Oh well.....A 2013 Silverado 5.3L/6L80E E38 is $60 WITH connectors (cut offs), Plus $100 to licenses it via HP-Tuners. Then I can segment swap the engine calibration for a 6.0L Savanna/Express Van (Which also uses E38 ECM's)
Not to worried about the TCM....Even tough no E38 OS is compatible with the existing '17 TCM OS. But I've had great luck reprogramming (Non Global) T43 TCM's with GM SPS (Forcing a different OS into the module). I'm guessing that's because there's no VIN in the the TCM?

I could buy a small OBD dash (Like a Edge Insight)....But I'd really like the factory Speedometer & Tach to function.

Truck runs great & pulls like a freight train Though it's very traction limited off the line with it's open differential :sneaky: , Just need the EVAP monitor to ready. Even though it's allowed one not ready to pass state inspection.....My luck it would set a gross leak DTC because the vent valve or something as it's getting tested!
 
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I'd love to swap a 6L80E in my 2005 if the 4L60E gives up the ghost (230k original miles/10,100 hours currently). That would at least let the 4.8 wind up easier. I'm always catching first gear and screaming it to get up to speed at my preferred rate.
 

clinebarger

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Unfortunately I don't want the newer engine yet because I'd like to break records for hours and mileage on this engine. Lol

Whose record? There are some "Hot Shot" Express & Savana Vans that have insane amounts of miles. One 2008 Express 3500 6.0L/4L80E I know of has over a million. Trans gave up at @ 950,000.....It was so wore out I was able to use 3 or 4 parts.
 
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clinebarger

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Got the E38 ECM swap done over the weekend, It was pretty easy albeit tedious.

Started with Connector X1 Pin #1 of the E38 & search for that Circuit by the Circuit Number on the E78 Pinout......Not the circuit description, Not the wire color. And just populate the connector 1 wire at a time.

You kinda got to untangle the wires out of the harness because the circuit you need out of the E78 are spread over 3 connectors. The wires had a memory from where they've been for years. After I got done pinning all the circuits.....I used a heat gun on low & some patience to get them to lay together.

The 2 circuits hanging loose are the VSS & Tach outputs as the harness didn't have them.

Was able to flash the TCM to the VIN stored in the E38 using GM SPS.

Segment swapped in a 2013 Express L96 Engine Segment & 6L90E Trans Segment using HP-Tuners. The VE Table & Injector Flow data is quite different than a LMG 5.3L. And Clutch Apply Volume Indexes are different between 6L80E's & 6L90E's

Set-up the VSS & Tach Outputs to match the GMT800 Cluster, Set the Tire Height & Final Drive Ratio, Disabled both VATS patches, Disabled the Starter Diag Routines.

Tach & Speedo work perfectly! Truck seems to run & pull even better (placebo?) after I relearned the Transmission.

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Whose record? There are some "Hot Shot" Express & Savana Vans that have insane amounts of miles. One 2008 Express 3500 6.0L/4L80E I know of has over a million. Trans gave up at @ 950,000.....It was so wore out I was able to use 3 or 4 parts.
I'm unlikely to beat those records but hoping for a million kilometers. My engine went from using a qt every 2500 miles to now using half a qt in 5k miles after I replaced the drivers valve cover (plugged PCV).

It runs so good I'm hoping it will keep going for years still. The trans still works good but I'm sure it will fail before 500k.
 

clinebarger

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One thing I forgot to mention on the punch out list......Couldn't get the A/C Request signal from the HVAC Control Head to kick the Compressor Clutch Relay Coil. I jumped the relay to get the system charged....Blows really cold by the way!

Searched/Googled for some remedies, People just don't Gen IV swap GMT800 trucks, Not that I exactly blame them! And the very few that do run a 24X to 58X converter boxes & run the factory P01/P59 ECM & Harness along with a 4 speed auto.

Did some testing on the A/C Request signal, Has around 20mA of carrying capacity before the voltage starts to seriously degrade. My Relay has 75 Ohm's of resistance on the Coil & takes roughly 160mA of current to close the contacts.

There MUST be a Resistor inline on the board of the HVAC Module between the 12vdc feed out of the A/C Button micro switch & The Module Connector Pin......(To protect the Micro Switch from shorts)

Alrighty.....I need a Transistor to amplify the signal! I usually buy stuff like this from Mouser Electronics but they're 20 miles away & seems to take forever to pick-up a will-call.

Found an old Amplifier in my Conex, Had G-Spot branding on it ;), Probably from the early 90's? It did have several SEC Transistors & a good heavy duty Diode that I unsoldered from it's Board.

*Wired the A/C Request to the Base.
*15 amp Ignition Hot circuit to the Collector.
*Relay Coil to the Emitter.
*Used the Diode for Inductive Kickback/Flyback protection.
 

clinebarger

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I was doing some full throttle data logging yesterday & noticed my airflow mass (Grams Per Second) was noticeably low. Couldn't really tell per the "butt" dyno but I don't have L96 powered 1500 to compare it to either.

My first thought was Exhaust as it's 100% stock 2000 LM7 except the Exhaust Manifolds, But after reviewing the MAP Sensor logs....I didn't think the exhaust was a major restriction.

Looked closely at the air intake, Specifically the original GMT800 LM7 part of it as the L96 air intake tube won't clear the hood. It was pretty clear that the GMT800 is more restrictive than the K2XX piece.

Found that 2007-2010 2500HD's (LY6) don't have the "3rd" Resonator in the Intake Tube & looked like it would fit. Called my local Wreaking yard & they had one for $30.....Worth the risk!!

Airflow is now normal, MAP logs now show a bit of Exhaust restriction at the Very Top of the curve (5,700-6,000 RPM) Nothing I'm going to worry about.

Getting this out of the way will allow me to tune the Open Loop WOT Fueling which is always WAY too FAT!!!

*1st pic....K2XX/'11-'13 GMT900 L96 Intake.
*2nd pic....Why GMT900 1500 Intakes don't work, The "3rd" Resonator will not clear a mechanical fan shroud.
*3rd pic......My "rigged" GMT800 Intake.
*4th pic.....'07-'10 LY6 GMT900 Intake.

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Impressive.

With your wiring skills and skills in general (yes, I been stalking your transmission related posts), have you looked into the rabbit ecu???

With your skills, it would take no time to whip one up. Make a digital dash that would rival holley.
 
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Super cool project. I can barely unhook a wire connector without causing damage. Just seeing the pics of those wires out of the loom gives me agita.

Roughly how many hours did this take? Is it running and on the road?
 

clinebarger

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I didn't keep track of the hours I spent, It was too many to ever come out ahead if I ever sell it. I've never seen a L96/6L90E swap in a GMT800 & I thought it would be cool.....And it is in my opinion.

I've put @ 100 miles on it, Needs tires, Front suspension work & Brakes. The truck will be painted before any of that gets done.

It's getting a GMT900 front brake conversion using Powerstop components & Replacement Powerstop on the rear.
 
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