how good are service interval indicators?

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Triv

Member
Joined
Mar 20, 2011
Messages
37
Location
Bristol
Car
s210 e300 td 1998
Hi all,

I ask this because since buying the car in May but only having driven about 1k miles in it, the service interval indicator hasn't budged from 9k miles to next service.

Can it really tell the quality of the oil in the engine? if so how?

Is it possible / likely the indicator could be 'stuck'?

Could the previous servicing garage have 'fixed' the figure at 9k, or even broken it somehow?

Or are these indicators really that good and I'm worrying about nothing?

History does show it to have been serviced with Mobil1 a year ago and I have read that star can be used to set oil quality but I'm also certain that the little garage that performed the last service do not have star.

Thanks for your time and apologies for so many questions first thing on a Sunday!
 
Perhaps depends on what sort of miles that 1000 was? If it was high speed motorway miles with the engine fully warmed up----- then maybe not if the car is on some form of extended service interval servicing regime. Check the mileage when the car was last serviced and keep an eye on your present mileage and see how things go
 
I get about 15000 between oil changes. Nothing to worry about...but drive that car...it wants it.
 
As said above, it depends on driving conditions and other parameters.

On some models it is possible to set the parameters for longer service intervals (13k as opposed to 10k) based on the quality of oil (229.5 / 229.51 as opposed to 229.3) and the oil filter type (Microfibre as opposed to paper element)

Also, if you have an oil quantity sensor (i.e. no engine oil dipstick), then the car will know whenever you have added oil and will extend the service interval accordingly as the old oil is being partially refreshed with new oil.

There are some suggestions then on certain type of engines there is an 'oil quality sensor', that tests the water contents of the oil by passing an electrical current through it, and somehow works-out a crude estimate of the oil quality from that, though it is not clear how this actually works and at any rate not all engines have this.

And ultimately, if you don't do the mileage, the service indicator will come on anyway, on a time-based interval rather than mileage.

The whole thing is a bit of black art... and the progression of 'miles-to-next service' is by no means linear or logical.

Furthermore, around 2007 MB changed the time-based service regime from flexible to a rigid 1-year interval, because of complaints from fleet managers and contract hire firms that the flexible regime makes it very difficult to accurately work out the costs or plan the service schedules in advance. So the whole servicing regime is far from being an precise science...

In short, just go by what the car says and you'll be fine :)
 
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Hi,
I have always religously used the service indicator and because of the type of driving I do (mainly motorway) I get around 18,000 miles between services. Looking at the miles left to service I have actually had this mileage figure increase on me once I had topped up the oil.
 
Mine seems to have been quite accurate.

I bought the car in March this year, and it said there was 9000 miles left and a C service required.

Then it changed to an F service (it had been sat around / stop-started when for sale), and then back to C the more I used it.

Come a couple of weeks ago it said it was due and when I look back through the book, it was done November last year...
 
Hi all,

I ask this because since buying the car in May but only having driven about 1k miles in it, the service interval indicator hasn't budged from 9k miles to next service.

Why should it have counted down, the car has only done 1000 miles since it was presumably reset back to it's 10,000 start point.
As you drive it will count down, generally in a ratio of 1 mile on the countdown to 1.3-1.4 miles actual mileage.

if you fail to do enough miles to warrant a service in 2 years it will call for service based on time.
 
Thanks for all the input people.
Just got back from an 80 mile round trip, driven at anywhere between 30 and 90, parked it and still its 9000 miles to service. I like this car more every time I drive it!
 
Why should it have counted down, the car has only done 1000 miles since it was presumably reset back to it's 10,000 start point.
As you drive it will count down, generally in a ratio of 1 mile on the countdown to 1.3-1.4 miles actual mileage.

if you fail to do enough miles to warrant a service in 2 years it will call for service based on time.

Actually it might not quite do this. The calculation is pretty much spot on BUT, the service indicator (press mileage reset button twice quickly) should count down in 100 mile increments. So, given that OP is driving an s210 (from the same era as my w202 c230k) and presuming it is using "assist plus" which indicates one or two spanners for A or B services then something doesn't sound entirely right to me. I obviously stand to be corrected, but if the car has done 1,000 miles it ought to have shown some decrease in the 10,000 mile figure which should be reset at any service (but in reality can be reset by anyone who knows how). From memory the maximum multiplier I achieved on the way to Moscow was around 1.6x real miles.

Les
 
I obviously stand to be corrected, but if the car has done 1,000 miles it ought to have shown some decrease in the 10,000 mile figure which should be reset at any service (but in reality can be reset by anyone who knows how).

Les

This car uses ASSYST, as opposed to ASSIST +, but irrespective, it has counted down from 10,000 to 9,000 miles, so appears to be working.
 
I thought the point was that it was STILL on 9,000 and hadn't moved EVEN THOUGH he has travelled around 1k miles. If ASSYST counts down in 1,000's not 100's then maybe it is okay. But I have assyst plus and that uses 100's. So you are saying that the older version counts in 1,000's?
Les
 
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The older ASSYST also counts in 100 mile increments, but as it starts at 10,000 miles, would appear to be working.

He will know after more use.
 
Thanks for the info. Maybe the Op has got his figures mixed up. I do take your point about the 9k. It didn't get there by itself.
 
Thank you all.
I'm certain I haven't got my figures confused.
I'll drive it some more and post back...
 
Hi chaps.
Took it out this evening around town in rush hour. Jeez what a nightmare commuters have. Why on earth would anyone want to drive around at that time?
Anyway, I crawled around at next to no miles an hour for 90 mins and then booted it a few times as the roads cleared up. I also stopped and brimmed the tank with V-Power.
Arrived back home and lo and behold 8900 miles to next service!
I'm relieved that the service interval indicator is working but also pensive because I now know I need to start saving for the coming B service!
All of the previous miles I've done in the car have been motorway miles at a steady 80+. I'm guessing that the car enjoys motorway driving more than the rush hour nightmare it endured tonight...?
 
I just changed oil on my E300DT after making 14,500 miles since the last change. Still had 600 miles till scheduled service, but the engine was low on oil, so instead of adding I just changed the oil.
I do oil tests and have sample ready to mail to the lab. The last test had only one bad point, what was higher iron what seems to be Mobil1 generated. I will try to post new results when they come in about 2 weeks.
New oil is Shell Rotella T6. I have been using it in my Ford diesel with excellent results. Way cheaper than M1 too.
 
BTW. I doubt the car is actually testing the oil. I drove for a day on new oil without reseting FSS. It still was indicating 600 miles till service on new oil. I think it is the software program that adjust FSS depends on driven speed.
In the past I was towing heavy with ML320 and FSS was still giving me the same intervals about 13,000 miles apart.
 
1,000 miles without any reduction in the "miles to next service" is not possible in my experience. I have driven my car on the continent for long stretches covering 1,200 miles at a time and the "miles to next service" fell by around 800. Your ASSYST seems to be "working" as it is now on 8900. However, given that your assertion is correct (you travelled 1,000 miles ("1k miles" your words) and the "miles to next service" stayed at 9,000 miles ("9k miles" your words) then it might not be counting down properly. I would suggest that you keep a note of the mileage and the "miles to next service" for a period in order to monitor how quickly it is reducing.
 
I've had two of these aging work-horses, and don't worry over-much with service interval indicators.
I do approx 20,000 miles a year.
I change the oil and oil filter every 10,000 miles (Next one due at 170,000 miles).
I change the air filter annually before the MOT.
I change the fuel filter and pre-filter every two years.

Regarding oil, I don't use anything better than the correct MB spec oil ... Usually Millers semi-sythetic for turbo diesels.

Other service items, safety, brakes, steering, tyres, etc ..... As and when required.
 

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