davester

Yeah it should work no problem. Also make sure the torque converter is properly engaged with the pump in the transmission AND that it doesn't come out as you are installing it. If, when the transmission is bolted to the engine and the TC is pressed up against the flexplate and doesn't easily move (as in, pushing with your hand) back into the transmission, unbolt the transmission, move it back a bit, and then get the TC engaged with the pump again. There should be some space between the TC and the flexplate when the trans is bolted to the engine, so you have to pull it towards the flexplate to bolt them together. Failure to do this, you likely will destroy the pump in the transmission once you start the engine, necessitating removing the trans, replacing the pump, and cleaning metal bits from the transmission...

Running out of fuel robably wouldn't, but if the line was chewed downstream of the fuel filter, perhaps some debris went through the pump to the injectors?

Um, no? GM never used that in their trucks. If your truck has it, someone swapped it in there after the truck was made. My truck also has the G80 rpo code, but it has an open diff now...because someone swapped it in.

Did the mechanic use a bidirectional diagnostic computer to see what the tcm is doing? Or just suggesting parts for you to throw at it?

Yes, the fuel sender unit in the fuel tank is an all-in-one unit, fuel pump, fuel filter, fuel pressure regulator, fuel level sensor.

It's my understanding with the trucks, they did only use the Allison. I think they stuffed some in vans with the 4l80e.

From brief googling, it should bolt up to the allison, so that would cut down a lot of work. You'd have to sort out flexplate/starter/engine mounts and then clearance around the front of the engine (as the engine is a little shorter, you still want the fan in the shroud to pull air through the radiators). And you may want to regear it as the 6.0 will be happier with 4.10's vs I think the 8.1 normally gets 3.73.

The 8.1 comes with an Allison. You don't need to replace the front/rear diff, but the driveshaft will be a different length and you probably would need some adapter u-joints.

ok, you don't need to do the engine harness, bcm, ip. Still need to change all the driveline parts, and rewiring the transmission harness.

Just to follow up with your original idea, you need the engine, transmission, transfer case, wiring harnesses at least for the engine, transmission, and to the bcm (unless you like diffing the wiring diagram and repinning/wiring stuff, ecm at least, custom fab a driveshaft, possibly the front one as well, instrument panel (it's programmed different between gas and diesel), if the two trucks have different option packages, that is more work to either transplant or get it going. And that's it you transplant in the 6.0/4l80e Edit: Oh yeah, I believe the radiator, shrouds and metal piece (forget the name of it) that goes across the front of the truck holding the radiator are all different as well.

hit a junkyard...

You MIGHT find the wiring for your truck on Light Duty Prior To 2013 - GM Upfitter , but I wouldn't count on it. If it's not there, I would suggest a subscription to the full-service manual at a site like Do it Yourself Automobile Repair Manuals - Mitchell 1 DIY , it'll have the wiring diagrams, as well as all the diagnostic and repair procedures for getting the truck up to snuff and staying that way. And don't run the starter too long, and wait between running it, starters die when they overheat...

Well, you can test the wiring harness further along the chain to see if the button works, or use a more advanced scan tool to see if the bcm/ecm/tcm is told the button has been pushed, and should be able to turn the tow/haul light on the IP on/off (perhaps the bulb has burned out, I don't recall at the moment if the bulb is incandescent or LED, GM wasn't consistent in their use).

Google "duraburb". It can be done, but it's not as easy as it seems.

It's not clear what truck you are referring to, that's not working with your trailers. You started with your '19 Silverado, and said they all worked fine with that truck, then to "the Silverado", where they didn't work, and then the 4Runner, where they did work. So were you referring to the '19 Silverado, or the '07 Silverado in your profile info?

IDK, but you at least need to indicate what mirrors your truck has (as it can have several different ones, each of which works differently). Perhaps post a pic of them?

No.

I just hit a junkyard and get a handful...

...probably won't get a response, Platinum LBZ hasn't logged into the site in more than 2 years...

In particular, the speed sensor at the rear of the transfer case would be the first thing to check...

It's on '07.5 or newer...

Pretty sure no GMT800's had cylinder deactivation. That didn't start until some of the GMT900's...

Don't work on the truck right before the trip unless you absolutely HAVE to. Nothing like stressing out over having something go wrong while fixing it, or it's the wrong part, or whatever right before the trip, and then rushing to get it done so you can go on the trip (which makes it more likely something goes wrong with doing the work). Do some reading up on how the specific trailer brake controller you have works, how to set it, and then spend some time configuring/testing how it works with the trailer, after it's loaded, before you get out on the road in heavy traffic. You want to make sure it's working right before you get into traffic and/or on the highway.

You might look harder on gmupfitter, it has offsets for where the frame crossmembers are, how tall it is at various points, where the body mounts are. Only thing it doesn't appear to have is thickness of frame metal, which is trivial to measure...

Oh yeah, all kinds of stuff can be wrong and the CEL will be off, it's only used to notify you of emissions related problems, not problems in general. I would suggest getting a tech ii from ebay/amazon, not that much more than a more advanced code reader (one that can get stuff from the tcm, abs, srs systems), but it can read codes from all the computers in your truck (there's more than 10, varies with what options you have). You can pay to diagnose the problem, or pay to randomly throw parts at it hoping to fix it...