Question.i have a 02 dakato that i has installed a 5.9l .I am having a hard time getting a pcm.do I really need to give them the vin to the truck an if I have too.can I get a vin from a same truck that is at my local junkyard.
Based on personal experience I'm pretty confident it didn't matter on the 3.9/5.2/5.9 Magnum engine family in 98-99 and that may extend to the 2000+ 5.9.
I had a 98 V6 I swapped a 98 5.2 V8 into. Only swapped the engine harness and PCM with no issues. (i.e. the ABS, CTM and cluster with VIN#1 played nice with the PCM with VIN #2.)
I later swapped in a PCM from a 99 5.2 Ram (found one without the "authorized software update") with no issues.
ALSO, I currently have a 99 5.2 V8 with a V8 MT PCM that's supposed to have the VIN from a V6 truck programmed into it with no issues. (PCM VIN does not match ABS/CTM/cluster VIN in this truck either.)
My understanding is that if you have an oval gray key you have to program the VIN. If you have a black headed key then you don't but if the donor computer comes from a gray key truck then it needs to see the matching key and ignition switch.
Also if 2001+ definitely need VIN at key and computer to agree. Or it'll start and quit start and quit before you can get your hand off the key switch.
I ran into this with my Durango, it pissed me off to no end, a few years ago. Was a long aggravating ordeal when my computer went bad and I tried to replace it with a known good unit and it wouldn't run my truck.