If an OCI was 7.5k miles, would you be comfortable running it for 2 changes = 15k miles? Factory schedule is 10K miles of course.

 

First of all what Filter is being discussed? Engine Air, Cabin Air, Engine Oil, Transmission etc....?

 

That is engine oil filter. Change it along with the oil is best. You wont want pressure drop.

 

You probably "can" but why? To save about 8 bucks? Oil and filters are cheap insurance on engine internals. Now, even with that said I think these are very good filters:

https://mbworld.org/forums/e-class-w...lter-pics.html

 

always always always change the filter with the Oil. Every time!!! I even change the engine air filter and Cabin filter every time.

 

Personally I change the filter every 5K. It really comes down to conditions, style, temps, ie:city style driving is considered ‘heavy service’ and reduces your change intervals in half vs highway.

You just don't want to get to the point where the oil goes through the bypass no longer being filtered.

 

Maybe I should have posed my question differently.

Which would be worse: Not changing an oil filter as often as your socks or running with scissors in your hands?

 

That would depend on which you value most lol

 

I run a Blackstone oil analysis once a year or so on each of our vehicles to get a general picture of what's going on inside the engine. You might want to consider something like that as it relates to your particular driving conditions, oil selection, etc.

 

Change the oil and filter on the recommended schedule which is every 10k. You can buy the filters online in bulk if you intend to keep the car for a while. They are good filters but why on earth do you want to risk extra wear cheaping out on maintenance on a German car?