MMRanch wrote on 03/22/20 at 09:44:42:I remember dad telling tales of the older 1950's cars not lasting 100K miles. I figured that might have been from inferior oils ?
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I believe a lot of things have contributed to the higher mileage that vehicles can obtain. Oils are better, engineering/manufacturing/materials are better. I also believe that fuel injection has added a lot of life to the piston rings and cylinder walls - when we had carbs and chokes the fuel mixture with the choke out was too rich and washed the oil off the cylinder walls. Another big contributor is the highways and taller gearing in vehicles - it used to be that cars and especially trucks were geared low, and highways speeds around the rural area I lived were 45-60 mph, and trips were generally short. Now cars all have overdrive and the engine speeds are low at highway speeds.
When I was in my youth a car with 100,000 miles was generally worn and burning oil - especially 4 cylinder cars. I could not afford new cars and I bought older cars that were getting worn - my VW Beetle/Bus cars all got total rebuilds, My BMW 320i, Volkswagen GTI, and Audi Fox all got rebuilds with the block still in the chassis - the cylinder heads came off and went to the machine shop, and I pulled the oil pan and pulled the pistons out, and put in new rings and rod bearings.....the cylinders were good but the rings were worn, and the valves and seats needed refreshing. The BMW had worn rockers.
Once the fuel injection became standard.....I believe cars began to last considerably longer, and cars with 300,000 miles are around. My 2006 Pontiac Vibe now has 166,000 miles on it and it runs great - I would not be surprised it it makes it to 250,000 miles!
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