Maybe a bit much for my taste but the M-20 engine is one of the toughest, longest lasting little engines out there! Just keep good maintnace on it, valve adj. and t-belts etc. and it will go a long time! They have diesel like longevity! No real reason to run high octane gas in them, they dont have as high compression or nearly as picky as the newer engines;)

Funny thing, oil. I have known a fellow with an '83 Chrysler 4 with 280.000 miles, said his nephew, a mechanic advised him to use Mobil 1 synthetic, not change it, mind, but just add as needed. The goddamn car seemed as good as new. My Gramps Stearns-Knight was another vehicle that suffered {benefitted} from infrequent lube changes...Approx, 350 thousand mile later, it seems to have borne fruit as I drive it weekly.

When I had the FIAT 128 Wagon, I'd drive 60 miles a day, highway. After a fresh LOF (with Castol GTX 10W40 during the warm month(s), 10W30 during the winter), I'd get 33 MPG.

Around 2.5K-3.0K, my mileage would start to drop off...by the time 3K was clocked on odo, I was down to 24-25 MPG...

I'd head off and do a LOF...the MsPG would jump right back up to 33 MPG.

Coincidence? I don't think so.

You could stick your index finger and thumb in the old stuff...you could "feel" the "sticktion" between the digits...still somewhat slippery, but not like out of the can. Stayed with that routine ever since 'til...

'Til the MOBIL 1 phase, I changed the oil and filter at 3K tops...and I felt like a criminal going anywhere over that...now, anything MOBIL 1 gets changed at 6K and I'm still running, trouble-free, on the same engine...that S-10 has 317K on the odo and I made the switch back about mid-150K.

All I can say is YUCK!

That was my take. The whole thing was a sort of goofy troll like ego trip. Must have been 4 or 5 threads with "her" going on about what dummies people were for changing their oil.

And here I am wasting time over it.

I've heard that those engines are bullet proof. I need to adj. the valves. It's been a while.

T-belts, I done got religion on that one. A new one every 50K. I once saw a 325 motor splayed out awaiting a re-build after a T-belt broke. A third to half of the valves bent to hell. I'll be doing a third one in about 10K.

We had an E30 328i w/ 5spd come in our shop one day, complaint was, he was driving and all of a sudden a terrible clatter and died. Well it seemed to crank over with a bit of a limp but it sounded like it had good compression and wanted to run. Looked in the oil cap, cam was turning, had spark, had fuel just flooded a bit. I gave it a shot of brake clean and it fired up. It was making a nice knocking sound, and running rough shut it off. and there was a nice oil puddle under it. I then found it had lost the oil pump drive gear and cover. (where a conventional distributor goes in a euro M20) Everything looked undamaged what i could see. Poped a couple of used ones in and now it had oil pressure but still knocking. We figured it prolly spun a bearing since it lost the oil pump for who knows how long. Dropped the oil pan.....WHOLLY CRAP! A whole connecting rod was laying in the oil pan! The piston was in a ton of pieces, wrist pin still with the rod. Bearing even looked ok cept for a couple of dings. A rod cap bolt came out and it snapped the other. Then the crank must have whacked the free rod and took out the piston and poped the oil pump drive! All that happened and it still ran! Another we had a kid mis-shifted it and whacked the valves and it snapped one of the exhaust valve heads off, kept driving brought it to us. Pulled the head (was stuck to the block) and found the most unbeliveably hammered piston/combustion chamber ive ever seen. It eventually slammed the valve head through the piston top sideways where we found it. Still ran....

Very tough engines!

It is said you have to wear chain mail underwear when you drive those...

I wonder if you could run some marvel mystery oil through that a few times as well as an engine flush and have it operate as if nothing happened?

This is pretty awful. The worst I ever saw was just some orange varnish on the valve train with the occasional stalactite or stalagmite.

It almost looks like the thing was sabotaged some how... Or maybe a wedding gag gone awry...

But.... That many miles... I guess it all adds up (literally)!

and nothing else? :D

I've seen much worse that that on older engines. Today's oils are so much better than those of 20-30 years ago that heavy sludge is a much rarer occurrence than it once was.

That is tough. Even with the mileage on mine, still has a lot of punch. A good bulk of the miles have been on long hauls on the highway. Original owner had a 40 or 50 mile one way commute. Similar with me - clients scattered around the Bay Area. Plus at least 8 or 9 round trips to WA state with Craigslist carpool riders -- about 13 to 14 K right there.

Aye, and we were 20 miles above the Arctic circle in a remote corner of Finland. At least 700 miles to even a trace of real civilization, and we throws a rod in our 325i. Some kind of serious racket so we had to limp home keeping it under 80 kph the whole way. Rebuilt it - still runs at 463K.

I won't lie...I only changed the oil in my old Ranger when I had time....probably 6-8k between changes.
Was religious (3-5k) with the Benz and my Buick

I've seen worse. I was in an Auto Parts store in Tulsa OK. Some guy walked in with an oil pan, from some type of V-8. I remmeber it being a Chevy. The sump of the oil pan looked like it was filled with grease. I mean the whole sump, filled. The guy asked me and the guy at the counter of what to do. We both sort of shrugged our shoulders. The guy then said the rest of the engine was as bad. I think the engine either had a coolant leak and/or didn't have a thermostat in it.
I do run my Ford Contours on a 7,500 or more oil change. I use synthetics, but Group 3. I have 214K on the '96 4cyl. I have gone over 10k between oil changes on it. The vale train and head are clean, only varnish is around the head gasket.
Tom