1980 Seville w 17,800 miles - $11,500 - Diesel

[BJM]

https://phoenix.craigslist.org/nph/cto/d/scottsdale-1980-cadillac-sevillemiles/6794730560.html

I was right there until I saw Diesel.  But still, pretty much archival level and I like Brown.

[James Landi]

So just how "bad" was the diesel?  Having own( 4) 4100 laconically powered and ill fated Cadillacs, I am  aware of commentary, but very little has been stated about the diesel option on these cars.  Were they simply under powered, or were they prone to prohibitively expensive repairs like their 4100 contemporaries?.  This example seems truly attractive.    James

[Eric DeVirgilis CLC# 8621]

A good amount of diesel-related engine issues in the field resulted from a lack of special maintenance which many owners were unprepared for.

A number of significant improvements took place in 1981 and after and most 1980 and earlier cars got the improved GM Goodwrench replacement engine. I have no idea whether the engine in this car was the subject of such a replacement but I'd be a lot more comfortable with the car if it had.

Can't be many living 350 diesels around today and they seem to have developed a bit of a "cult" following, particularly with overseas buyers where diesel use is more common. I don't know the last time a diesel Cadillac showed up at a Grand National but chances are this would be the only one if it was entered.

[Big Apple Caddy]

The earlier GM diesel engines were worse (too often requiring complete engine replacements) than the later ones but the bad reputation tarnished all of them.  Resale values by the mid to late 1980s were much worse for diesel equipped GM cars compared to equivalent gas engine models making them appealing for buyers looking for "bargains" and willing to take the risk.

[BJM]

Still too much money for me because of what $11K can buy in the marketplace I look in.  Aren't those "real" aluminum rims, those are nice. 

The issue with the Diesel is that who is going to work on it if it needs a major repair. The technicians from that era that did replacements are gone.

[35-709]

Not to mention the weak transmissions they put behind those diesels.

[kevinanderson]

I have a 79 eldo, 81 SDV and 82 Biarritz. And an 80 Seville I foolishly parked in the weeds. The only problems I encountered were head bolts breaking. Usually because they were nt warmed up well. And not using a quality diesel oil and keeping the pvc  system clean.  Most of the diesels I tore apart had carboned/stuck to the piston rings. Mileage was fantastic. But rolling up in  a good looking cadillac that rattled and smelled like a truck was wrong.

[INTMD8]

A number of significant improvements took place in 1981 and after and most 1980 and earlier cars got the improved GM Goodwrench replacement engine.

In 1999 I worked for an Oldsmobile dealership and being the new guy was -lucky- enough to receive the job of installing a diesel GM goodwrench long block into a (I believe) 1983 Buick Riviera. 

An older lady bought it new and it was all rusted out but she loved the car and wanted to keep driving it.

At the time I was told by the parts department that it was -the- last diesel long block in existence.  Not sure if that was true or if they ended up building any more after that.

[Big Apple Caddy]

Mileage was fantastic. But rolling up in  a good looking cadillac that rattled and smelled like a truck was wrong.

While probably mostly due to my being a fan of Mercedes as a kid and so many Mercedes being diesels back then, I actually found the diesel engines in Cadillacs and other GM cars made them more "luxurious" rather than "truck like" despite the clatter (which I liked) and smell.   Also, most of the GM diesels I encountered back in the day in addition to Cadillacs tended to be well optioned, top trim models e.g., not a base Oldsmobile Delta 88 but rather a loaded Delta 88 Royale Brougham, not a base Buick Electra but rather a loaded Electra Park Avenue, etc which added to the luxury factor.

[Eric DeVirgilis CLC# 8621]

I agree - diesel option tended to be more common on premium models rather than base. We only had a few diesels on the lot back in the day. They were an '80 Delta 88 Royale Brougham Coupe - 2x black with camel velour; '80 CdV - 2x white w/red leather, '81 Caprice Classic sedan - well equipped, med blue met w/dk blue cloth (best running of them all) and an '80 FB d'E Sedan - 3x Navy Blue w/leather and every possible option.

I always noticed diesels seemed to have less rust than the gasoline versions of the same car as they became older. I think the soot they produced acted like undercoating which helped to preserve them.

[V63]

Adding to the corrosion topic, the diesels were heavier undercoated for sound deadening ...moreover,  the demographic that could afford them new were more probable  to take better  care and garage them ?

[Uhegej]

I love how this car looks, however, I think it's over priced.  It has nice rims, but besides that seems very much a base model.  My mother, had an '82 and '85 Seville, I drove both of them as a teenager, the 4100 was a slug! slow take offs.  My dad had a loaded buick I think park ave, '84, it was nice to drive, I liked the diesel engine, it was 2 tone gray with a black and red pin stripe, velour seats.  We had that car in the family till 2001; still running and driving daily, but car accident took it away, insurance totaled it out.  That diesel Buick was a great car and acceleration was about the same at HT4100 IMO.
J. Hegedus

[79 Eldorado]

A friend at work has two Oldsmobile diesel powered cars but he is an incredible mechanic with a lot of experience with these. He told me once he would like to have a spare rebuilt injector pump on the shelf.

I've had two former Olds diesel cars. One of which was certainly converted due to the reputation as opposed to an actual problem as the car ran great. It was a 1979 and it already had the Goodwrench service block. I later found a lot of Oldsmobile people like using the diesel block to create a strong gas engine. As well if you have any problem you could always swap in and Oldsmobile 350 gasoline motor which was also used in Cadillacs in 1979. With some of the motors Cadillac was using by the 1980's the diesel is at least one you can easily do something with and still have all accessory brackets bolt right-up. You can keep the 7 quart oil pan; the dual batteries; the heavy duty radiator and as a bonus all of the Olds diesels I've ever seen came with the pretty rare full gauge packages (not certain if the Cadillacs had any additional gauges).

I'm now of the opinion it's pretty cool to see them preserved and they certainly get much better fuel economy than any other period motor offered.

[Eric DeVirgilis CLC# 8621]

Adding to the corrosion topic, the diesels were heavier undercoated for sound deadening ...moreover,  the demographic that could afford them new were more probable  to take better  care and garage them ?

The extra sound deadening in diesels would have no bearing on body panels which is what I was mainly referring to, and in cars that had long left the hands of the original owners which were by no means in great condition - except for the fact they usually exhibited little to no rust compared to their gasoline counterparts after 5 - 10 years of age.   

[BJM]

I thought the issue with diesel (non)reliability was related to adapting diesel to an existing gas engine, it not being a clean sheet design.  Don't diesels run much higher compression and I thought I remember the issues being related to the heads and block damage. 

Just not worth it to me for an OLD car.  I seldom purchase an older collector car, especially a Cadillac, for it's unique powertrain and/or performance.  I am after the style and experience of driving whatever it is.  Unless it's a muscle car or possible a sports car. 

So if the 1980 Seville was a car I wanted to add to my collection, I would avoid the diesel.  Just my opinion.

[Eric DeVirgilis CLC# 8621]

I thought the issue with diesel (non)reliability was related to adapting diesel to an existing gas engine, it not being a clean sheet design.  Don't diesels run much higher compression and I thought I remember the issues being related to the heads and block damage. 

If that were the case, every 350 diesel engine would self-destruct in a matter of seconds.

The only thing the 350 diesel has common with the gasoline engine is that they happen to share the same displacement. The suggestion that it was a "converted" gasoline engine is one of the greatest automotive myths of all time. 

[James Landi]

Wasn't sure just where to place this one for comment--- the article originates from the "GM Authority Blog," and seeing that it's about a limo with a diesel, it may only be tangental  to the the subject car... Please move it if you wish.   James   http://gmauthority.com/blog/2019/02/this-cummins-diesel-cadillac-dually-is-actually-pretty-awesome/