While you mention it, when I ordered my 86 Buick Park Ave., I wanted gauges. The only way to get them though was with the electronic dash which was either a $1 or 2,000 option, can’t remember. So at any rate I ordered it without and went down and bought a set of gauges for $20 and mounted it under the dash. Voltage, temp, and oil pressure all in one neat little case that looked OEM. So I still had the idiot lights as well as the actual readings of what was going on. My Acura doesn’t even have a voltage gauge so i just plug one of the $15 variety in from time to time just to see. As far as I’m concerned they can dump all the maintenance minders for all I care, plus anything beyond oil changes has to be reset by the dealer and their computer.
Guys there has been much engine damage by leave oil in the engine for to long…
GM and others have changed there ECM to actually tell you to change the oil sooner…
The reason has been due to cam chain failures. Or tensions failure Turns out once the additive pkg burns off the oil isn’t good enough to protect cam chains and chain tensioners…
Also
Most cars are rusted out but the engine is still in good shape
So mfgs are lengthening there oil change times.
This also lets them claim a lower cost of ownership…
Change your oil often. It’s not worth the wear and tear to have dirty oil running through the engine.