they want to hear about your old diesel!

[d rock]

another interesting article...
http://www.dieselforecast.com/Articl...?articleID=305

[lisa lebowski]

Well, I know of one example of the GM diesel that was in a little caddy - it was a dog - but it never gave a bit of trouble, didn't smoke particularly, and ran day-in-day-out from 1976 or so - when it was first sold - until it went to trade-in about 1995. I think GM built a pretty nice motor. At least that particular motor was just fine.

[Radio]

Actually the GM 5.7 litre diesel was first offered in 1978. Your particular engine was an anomaly, or you paid particular attention to keep the fuel filter clean and fill it up with only FRESH and quality diesel fuel.

Main problems with this engine overall was that owners had no previous diesel experience and drove the thing like it was a gasoline engine. They never, NEVER changed the fuel filter and were usually quite indifferent as to where they bought their fuel-- they had no experience to understand this was a critical part of diesel ownership. This ate up injection pumps and was entirely avoidable.

Main problems with your particular generation of this engine were that a) the head bolts were too skinny, leading to stretched bolts and lots of blown head gaskets-- then the equally ignorant GM dealer mechanics would just re-use the stretched bolts; b) the main cap bolt holes were often not drilled deep enough, causing the main bolts to bottom out before reaching actual necessary torque. While this happened a lot you might have missed it-- but the head bolt problem was pretty much universal. Can't figure out how you managed to dodge that bullet.

Mechanical deficiencies were addressed in a re-design (the DX block) released in 1981.

--Radio

[lisa lebowski]

Yes, and I think there were, in some cases, problems with the hardening on the cam/lifters such that GM went to roller-lifters later on. It was not my engine - it belonged to my mother, who had a soft touch, and had the machine regularly serviced at the caddy dealer in San Marino Ca - rich people get better service. She did not live in San Marino - but she knew a thing or two...

She used to drive it to work daily as well as from LA to Sacramento several times per year - and had a large after-market fuel tank put in.

My bet is that the dealership quality was pretty high and they paid careful attention to service flyers and regular GM training. As she and her husband were both lawyers they may have been especially attentive to getting a good job out the door.

On my advice mom bought the extended warranty - that may have been an additional incentive. The car was a dog though in climbing hills...

Lubricity of diesel fuel is quite variable, as is cleanliness. The LS fuel nowadays is also variable. I add straight-run 30# ND oil and marvel mystery oil to the fuel in the old 1L and also the ford diesel we try not to drive. Same for the red diesel we use in generators and the tractor.