Marty.

Thanks for the reply as I value your insight. The 15K OC interval was instructed to me from my dealer, whom I purchased the '99 on starmark. I questioned the "extended" length, even knowing it was synth. The service mgr demonstratively said he would call the factory and let me have the nice German man tell me the same.

If it is indeed, the FSS takes the cumulative driving conditions & provides the optimium OC, I will be going that direction. Good to know after 170K of driving.

Thanks for the clarification. BTW my bus DD 6V92 w/7.5 gal + filter is under $100...

Gary

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Gary
Experience is something you get, Just after you needed it....
'99 E300 295K, '83 300D 220K, '75 240D 185K sold
'80 MCI Bus Conv DD 6V92TA, w/4 cyl. Kubota diesel GenSet 12.5KW

FWIW your oil is probably just fine even up to 15K miles but what your dealer told you is not correct. I have never gone that far but always had oil analyses done and even at 12K the lab has said I could have gone further. I never wait for the FSS to tell me to do it, I just do it at 12K because I don't like driving further than that on an oil change...but that is being conservative and erring on the side of caution.

The factory produced the FSS for a reason. It adjusts service intervals based upon several factors and would not exist if there was simply a "rule" as to how often to change it. I'd be curious to know what they think the FSS does if it doesn't tell you how often to have service done?

It is also puzzling that they would tell you 15K as that is about the most you should drive between changes.

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Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz

It was my astonishment that prompted the call to the motherland. I was at 10K for the first 120K, but have been extending that to 12.5K. I agree that even synth. oil is cheaper than running the engine to the limits of the oil.
I do get annual oil analysis on the bus, but that is a 2 cycle engine.

Thanks and have a wonderful Labor Day.

__________________
Gary
Experience is something you get, Just after you needed it....
'99 E300 295K, '83 300D 220K, '75 240D 185K sold
'80 MCI Bus Conv DD 6V92TA, w/4 cyl. Kubota diesel GenSet 12.5KW

You too.

Sounds as though you (correctly) disregarded what they told you regarding the 15K O/C.
I'd bet that dealer has "Klaus" in the back room answering the phone "mit his haccent" to re-assure everyone who questions him

__________________
Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz