Back in the early eighties GM decided it wanted to put diesel engines in a few of it's 3/4 ton+ light trucks and even some oldsmobile sedans. Folks were familiar with the rock solid dependability and longevity of BIG truck Cat, Detroit, and Cummins engines along with the ever-present Mercedes 300D that just wouldn't die. Bear in mind this was when diesel fuel was cheaper than gasoline and at 100,000 miles you called the junkyard to come get that worn out car out of the driveway. Were folks ready to buy vehicles for longterm use? GM thought so.
Folks ordered them. And drove them. Back and forth to the dealership. Problems of all kinds. Expensive injector pumps, coolant in the oil, warped heads, leaking head gaskets. They were so bad that a myth was perpetuated that GM had "converted" gasoline engines to diesel and foisted them upon the public.
Years after the introduction of the GM diesel the aftermarket got into the act and started offering stronger replacement head bolts. Viola! Problem solved. Did I hear someone calling "Bullshit!"?? Look it up. For years mechanics circled around the problem replacing all the wrong things and causing many return trips to the dealership for warranty and expensive out of warranty repairs.
Now, just how could a company with the resources of GM spec fasteners that were not up to the job? Didn't they have trained engineers? What gives? Luckily, the corporate idiocy passed when Dodge speced a Cummins (cement truck) diesel for their 3/4 ton+ trucks and the working world beat a path to their door. Ford adapted and old International Harvester diesel and dubbed it the PowerStroke to great success, and GM upgraded the 6.5 liter with a turbo and some redesign, but not many were lookin' to take a chance on it.
Fast forward twenty years and look around; Dodge still uses the Cummins, Chevy got smart and bought Isuzu and is using one of there diesels to great success, but old Ford decided they were gonna improve the breed with their very own 6.0 liter all aluminum, variable vane turbo hot shit engine.
Guess what - weak head bolts.
