Though my enthusiasm for diesels has waned since owning a VW Jetta with one and the two 6.2's in my trucks,I cant really complain about either of them...the Jetta suffered a timing belt failure while idling,it still ran after replacing it,but I decided to sell it after suspecting it kissed a few valves ,it was starting to sputter--figured it was wise to ditch it before it grenaded eventually,but I regret selling it now--50+ mpg is hard to beat,and the car was still in remarkable condition for being 30 years old and having 252K on it when I got rid of it..
The 6.2 in my pickup was a salvage yard replacement of unknown vintage and mileage,but it has always started up for me well in cold weather after I replaced the 7 glow plugs that would come out...I've plowed at least 75 bad storms with the truck since getting it in 2003,but haven't put hardly any road mileage on it,I only use it to do dump runs and short local hauling,scrap runs,etc...so I bet I have put less than 6K miles on it in the past 10 years...the oddometer reads 34K and change,I have no way to know if its original mileage or if the speedo was changed,etc,but I do know the original engine blew at low mileage and it sat "broken" for a long time before I came across it...
One of the glow plugs decided to break off while I was doing a dump run a few years ago,it sounded horrible,like it spun a bearing ,it knocked,clicked and ticked all the way home...I decided to floor it once I got close enough to home that I could walk if I had too,and it must have blown the chunks of it out the exhaust...now one lifter clatters loudly until it warms up after a cold start,probably has a bent push rod or something...but I'm surprised it didn't just kill it and seize up...considering the fact I let the truck sit a long time between uses,I've had few problems with it really,I find vehicles that dont get daily use are often problematic more so than those that get driven often...
My 85 Suburban has the original 6.2 and has about 160K on it--sounds like its "tighter" than my pickups diesel is,but it does smoke some out of the drivers side tail pipe...might be due to the witches brew of fuel the prevoius owner used,he said he ran it on various mixtures of veggy oil,used engine oil and home heating oil..
...bet that is why it doesn't like to start too easily..it had almost a full tank (40 gallons!) when I bought it in fall of '09,it still has a 1/4 tank left,and I have ran that thing at least 10 hours sitting in it when I fired it up to charge the batteries...
Only things I dislike about diesels is the fuel costs,and some parts are expensive or hard to find for the 6.2's--and sometimes they can refuse to start up when its frigid out...I dont like the noise the diesel makes and the vibes,it sounds cool at first,but driving my pickup 50 miles feels like a trip to California when the engine sounds like it belongs in a backhoe instead of a truck...
--and they are not as easy to work on as a small or big block,maybe I'm intimidated too easily,but I dont think I'd feel at ease changing a water pump or injector pump on one...jobs like valve cover gaskets or replacing injector lines are not as simple as you think on a 6.2,nothing like doing v/c on a old gas V8 is for sure,the intake and fuel lines must come off,and that can be costly if your lines are rusted and break during removal......glow plugs can suck to get at and get out of the heads too...
I've seen many 6.2's go 300K with no real issues,but have seen many with snapped cranks and tossed rods,blown head gaskets at junkyards too..
I'm more at home under the hood of a GM product with a small or big block V8 myself..not a diesel...dont think I would attemt any repairs on a Duramax myself!...I hear they are a nightmare to repair,and parts are very expensive..I wouldn't mind owning a Cummins someday,but I hear they have their quirks too,like the timing gear dowel pin dilema for one..
. Who know how long before they would have blown a head gasket.
