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99 Suburban 6.5 to 5.9 Cummins Swap

I think what screwed me up was the charts don’t EXACTLY match. The wire from my sender is a single green, the charts say yellow. Does anyone know if that green goes somewhere else before it went to the ECU? If not, can I just run it into the old port? I don’t want something small and dumb to light my truck on fire. I assume it measures resistance, I know that’s how 2 wire senders work, but I don’t know for sure.
 
Are you using a Cummins sender or an ACDelco sender? Also, the 6.5 uses two temperature senders, one in the front of the left head for the instrument cluster gauge, the other in the crossover pre-thermostat(s)(iirc) for the ECM. As far as I know, they're not interchangeable as the instrument gauge sender is battery voltage-based and the one for the ECM is 5VDC reference signal based.

So, with the Cummins, which I am NOT familiar with, what does it use for the temperature sender(s) for a signal to a Dodge instrument gauge and ECM? You should be using the correct GM senders on your Cummins's corresponding locations, and just plug and play the Suburban's engine harness to the corresponding senders. It's damn late, I'll pull out my GM Factory Service Manual for my 98 Burb tomorrow and check the wiring schematics for the color coding for the ECM and temp gauge sensor wires.
 
Delco sender. Removed it from the driver side under the head, bought an NPT adapter and set It in the Cummins. It has always had a single green wire. I’ll keep looking through all data.
 
Ok, because of my apparent insomnia tonight, I just hit my 1998 C/K Factory Service Manuals. The Dark Green is the Gauge Temp Sender (single wire) that goes into the driver's side head by the front injector on the 6.5.

The Yellow wire into the PCM/ECM comes from the Engine Coolant Temperature (ECT) Sensor (two wire, YEL/BLK) that mounts in the coolant crossover and shares a common ground wire with the Intake Air Temp and Boost Sensors. You MUST use that specific Temp sensor into the Yellow wire to the PCM/ECM. This temp sensor regulates transmission shift points, among other things. If you're not using this sensor in your conversion, you need to find a way to install it in a corresponding coolant flow location on the Cummins as it is on the 6.5.
 
Then you want to hook up the Temp Sender that came out of the 6.5 driver's side head to the Dark Green wire connector in the engine harness that runs to the instrument cluster temperature gauge. The sender grounds through the block, one wire hookup.
 
Yeah, the two-wire (Yellow&Black) ECT sender normally controls the 4L80E's shift points and TCC lock up through the ECM and TCM. Since you've gone all MOPAR/Cummins drivetrain with a stand-alone TCM, no need for the ECT sender that was mounted in the 6.5's coolant crossover.
 
I'll tell you, owning the hard copy 4 Volume, 4,000 page, C/K Truck service manual beats the hell out of trying to use any on-line source, including GM's CD-ROM web-linked version (which I have, before I bought the factory service manual off of eBay). Worth it's weight in gold, covers every configuration of the platform/engines/transmissions. Body, engines, wiring, mechanicals, DTC's, troubleshooting all covered. The only things NOT covered in detail is the teardown/rebuilding of the automatic transmissions. Those are covered separately in the GM automatic transmission manual(s).
 
Thanks a ton, that makes sense and will be an easy fix. I'm just curious how it got disconnected.

Husker6.5 said:
I'll tell you, owning the hard copy 4 Volume, 4,000 page, C/K Truck service manual beats the hell out of trying to use any on-line source, including GM's CD-ROM web-linked version (which I have, before I bought the factory service manual off of eBay). Worth it's weight in gold, covers every configuration of the platform/engines/transmissions. Body, engines, wiring, mechanicals, DTC's, troubleshooting all covered. The only things NOT covered in detail is the teardown/rebuilding of the automatic transmissions. Those are covered separately in the GM automatic transmission manual(s).
Click to expand...
I've been meaning to buy a factory service manual, just haven't gotten around to it.
 
I got mine off of eBay back in 2010 for $50. Pristine condition, came from a dealership that went under after the '08 Crash. Had "Body Shop" ink-stamped on the edge of each volume. Once you learn how to use the index system (being prior military and using military -10, -20 and -30 maintenance manuals helps a lot) it is fairly easy to find anything you want.
@MrMarty51 , the line drawings in Chilton/Haynes are blurry crap most of the time because they are poor photo copies of the original GM Manual drawings. Oh, and the GM Manual's paper is of MUCH higher quality, too.
 
Husker6.5 said:
I got mine off of eBay back in 2010 for $50. Pristine condition, came from a dealership that went under after the '08 Crash. Had "Body Shop" ink-stamped on the edge of each volume. Once you learn how to use the index system (being prior military and using military -10, -20 and -30 maintenance manuals helps a lot) it is fairly easy to find anything you want.
@MrMarty51 , the line drawings in Chilton/Haynes are blurry crap most of the time because they are poor photo copies of the original GM Manual drawings. Oh, and the GM Manual's paper is of MUCH higher quality, too.
Click to expand...
YUP, when it come to the wiring diagrams I usually have to dig out a maggot flying gas, OOOPS, I mean magnifying glass. LOL
 
So I’ve been driving it around after work, trying to straighten out the kinks.

Temp sender works now. Somehow I clipped it when I was thinning the harness. 1 out of 50 ain’t so bad. I’ll take it.

radiator: so I did as what I believe most did, which is use a 2nd gen Cummins rad in the same place as the original GM rad. I have “self clearanced” a circle in the face of it and knocked 2 holes. Is there a low pro mechanical fan? Or should I try electric units? I’d like to keep mechanical though, they just pull so much damn air.

I bought a New alternator pulley to try and correct the inaccurate reading currently displayed. How can I find the real RPM to compare?
 
I ordered new motormounts from Adventure Vehicles NW. Disappointed in the poor fitment of the SSOR. It will be nice to have something that fits.
 
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