yeah, they go a long time.. I put 300,000 miles on one of my cars and probably only changed the air filter twice.Not often enough. I tend to think they're good for 100k alongside the spark plugs, and forget about it until then. I don't think so, but I have lots of lightly driven highway driving on my side--the higher one's mpg is, the less air going through the motor. I think 30k is the interval on all mine, and should (somehow) get into the habit of doing then.
pull it out and look at it, put it right back.
also depend on environment.
Buddy worked construction, had been a drought for the last 9 months.
says to me his F250 isn't running right, smoking a bit.
popped the air filter out to look at it and there was a half inch deep layer of sand and dust on it.
he drove around in a dust bowl every day.
I still remember working at a bus fleet in Detroit
and we leased 2 buses to Ford to use at the Rouge plant every day to haul foundry workers to the foundry.
oil bath air cleaners..
in a month those oil bath air cleaners had a inch of foundry dust sludge in the oil pan.
this air filter is from my Ram 3500, has about 40k on it, it is still good for use but some people think it is too dirty.
I think it still has some life in it