Hey all,
I've got this build up on a few forums, but this one seems really knowledgeable, so I figure I'd post progress here and get some valuable feedback! I've already started the build, so I'll briefly sum up whats been done so far. I bought this 1986 GMC K30, sans axles, from an owner who robbed the axles for a project and was going to part out or scrap the rest of it. I gladly took what was left. It's a Sierra Classic, so it's got AC, power doors, cruise control, and all the bells and whistles the truck could have at the time. Found some axles to stuff under it and went for a rip


The 6.2/465 combination was possibly the least exciting thing i've ever driven, so I found a 94 Dodge Ram to donate it's guts to this thing. I've been driving 12 vlaves since my first vehicle anyway, I'm used to them.



I'll try to set this build apart from the rest of the squarebody cummins swaps if I can. I've found a full set of King Ranch seats from a junkyard and promptly picked those up for the build. My goal is to modernize the interior as much as possible while retaining the classic look and styling. Not sure on the transmission choice yet, I've been really looking into the 68Rfe with a standalone controller. But I also do love my NV5600s. So that's up in the air at the moment. That's pretty much up to speed at where the truck's at now!

 

Awesome. There just isn't a better pickup-size diesel engine than the 12v cummins when it comes to durability, performance, simplicity, etc. Such a shame that they put them in Dodges

I worked at a Cummins dealership in the mid-late 90's, so I've had more of these engines apart than I could possibly remember. Mostly in buses and straight trucks... they really didn't have many problems in the pickups... except for the KDP of course. And even in the heavier applications, most of the problems these engines had were... self-inflicted. Like broken gear housings from hanging a big cast iron compressor off that aluminum gear housing, supporting the rear with a stupid little bracket that should've been three times as thick. And of course more bad overflow valves than you could shake a stick at til they improved that design.

But the basic engine itself is bullet-proof so long as some common sense is applied.

 

And yeah, that 6.2 was... mediocre at best. We had one in an 82 C30 service truck at a John Deere dealership where I worked years ago. Had a Turbo 400 transmission, loaded heavy with tools and parts. Had to weigh 10,000 pounds every day of its life. That thing had over 300,000 miles and was still going strong on the original engine, second transmission. We kept an extra tailshaft housing in the truck because the driveline yoke bushing would fail every few years... so we could just fix it on site as needed

That thing was laughably slow. Loud enough to cause hearing impairment. And gawd help you if you ran it out of fuel... nothing but a rag soaked in gasoline would bleed that system. But it did get about 19mpg which was amazing for a truck of that size and era. And it just. Wouldn't. Die.