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Highway miles vs. city: wear ratio

I have a 98 Ford Ranger with 235,000 miles on it. It burns no oil and gets the same mileage as it did on mile 1. If you did not know the actual mileage you would think it had only 90,000 miles. I believe it runs well because it has 80% highway miles. What is the wear ratio of highway vs city driving? Does a highway mileage car with 100,000 miles have the same wear as a city mileage car with 50,000?

I plan to see how my truck is running at 300,000 before I consider a new car.

No one really knows. There are just too many things to factor in. It is generally accepted that city is harder than highway and that is about as far as anyone can really say.

Highway miles gets the engine running nice and hot for a long time and stays at a relatively constant RPM. Also no starting & stopping, slamming on the brakes (ideally), etc.

A fleet of 6 Aerostar vans, driven 400 to 600 miles/day on mostly rural 2 lane roads, accumulated nearly 400,000 miles each. One required ann engine at 290,000 miles due to oil consumption/low compression. There was never a failure requiring a tow. Maintenance was THOROUGH.

Consider the number of motor revolutions per mile in city driving. Lots of idle time contributes markedly to wear along with the different gearing. That’s why wear on an engine may be more accurately determined by an hour gauge as found on heavy equipment. That’s what is used to determine our maintenance intervals. One hour at recommended maximum working rpm with everything calibrated off that. I wonder if cars would be better served with addition of hour meters.

Car makers address this problem by recommending “hard use” maintenance intervals…instead of installing an hour gauge.
So…instead of some ratio, I would estimate total engine revs. over time.

Just a thought…

I bet they had one of the better American made motors of all time…4.3L v6. Still used in many marine applications today. Have known of that service life and more of the 4.3 in GMC school bus applications. Great motor !

Aerostars are Fords. The Aerostar had either a 2.9L V6, which is pretty reliable unless you overheat it, then the heads tended to warp, a 3.0L V6, the vulcan all-iron V6, that is renowned for it’s durability, or the 4.0L Cologne V6 that is a bit thirsty but still quite reliable. If it was an early model it could have a 2.3L 4 banger or a 2.8L V6, neither of which was remarkable.

OOps, my mistake…I confused it with the Astro/Safari brands from GMC…and their 4.3L V6.