To add the nightmare that was GM Auto Dieesels in the 80!s,a friend of mine was a GM Tech rep in that era for the SouthEast. The engines were breaking crankshafts at 20,000 miles and no one could figure out why. This was back in the days of 12,000 mile warraties and people that bought big Buicks and Oldsmobiles were not happy about buying new engines.One day he was at a dealer in Waycross GA and there were 3 Buicks in with broken crankshafts. The Dealer was livid and was threatining all kinds of legal action etc. In looking at the cars he finally saw something in common.They all had a trailer hitch on the rear bumper. The dealer called the owners and they all said they towed boats and trailers. He checked with other dealers and other tech reps and that was the one common thing that all of the blown engines had.
So they figured out in that since GM has always had that real soft GM ride that the weight of the towed unit was pulling the rear of the car way down allowing the front to go up,so not enough oil was flowing to the front of the block,thus resulting in a broken crankshaft while under heavy loads.
Interesting thing is that the tech reps reported this to GM in Detroit,reccommened either no towing or a towing package with stiffer shocks in the rear. The Corporate GM folks took their usual arrogant stance and refused to alter the ride or rule out towing. The Dealers finally were telling customers not too tow anything if you had a diesel engine which POED GM but the dealer wants repeat business. If I recall right that engine was the basic 350 block strengthened to and modified to be a diesel.. This guy quit GM in the late eighties as he could no longer take the mentality that went on in Detroit.But I think they learned their lesson and now seem to be building some good products.
