Extended OCIs 27 years on.

[Shannow]

Bought a toy the other day, a 1980 BMW 323i.

Interestingly, the oil specified (in Haynes Manual) is "multigrade SE/SF", the OCI is 10,000 miles or 12 months, whichever occurs first.

Even got a sort of Oil Life Monitor on the dash, under the economy gauge. Dunno what it does, how it does it, or even if it still works.

 

[Camu Mahubah]

Is this the same car you posted pics of?...

 

[Shannow]

Yep

 

[ThirdeYe]

I know my Integra (13 years old now) specified 7500 miles in the manual. I recently ran Havoline DS for 4,300 miles and it came back with low wear and a TBN of 3.5, I think that they may have been correct in the 7500 recommendation

It's crazy that they'd recommend such a long interval with oils of the past, though. Today's oils could handle it

 

[bar1]

My 11 years old Audi S6 2.2 turbo quattro specified 15000 km (~9375 miles) OCIs. Severe service was 7500 km (~4687.5 miles).
Specified oil was VW 500.00 or VW 505.00, at that time it was conventional (or blend).

 

[Propflux01]

Many manufacturers recommended intervals like that. I know GM did in as early as the late 70's. Maybe a majority of those oils were that good..

 

[Jett Rink]

Quote:

---

Bought a toy the other day, a 1980 BMW 323i.

Even got a sort of Oil Life Monitor on the dash, under the economy gauge. Dunno what it does, how it does it, or even if it still works.

---

I don't know what the setup on yours is, but mine works according to the information in this link:
http://www.peakeresearch.com/silights.htm

Mileage is estimated based on the following formula:

e= a(1+t+r)

e=Estimated mileage
a=Actual mileage traveled
t=1 if engine temperature is below operating temperature, else t=0
r=.5 if engine is above 4500 RPM, else r=0

Example: If you traveled 5 miles with a cold engine running at 5000 RPM, the SII computer would actually "estimate" 12.5 miles traveled:

Solving for e:


a=5 (the actual miles traveled)
t=1 (because the engine was cold)
r=.5 (the engine was exceeding 4500 RPM)
e=5 X (1+1+.5)=12.5 estimated miles (from a trip of only 5 miles)

The five green "countdown" lights are there to let you know approximately how long it will be before the next time your Oilservice or Inspection light will come on.

 

[Dad2leia]

Based on that formula, are today's OLM based on the same type of computation, or have they added a few more variables to that equation to better guage the oil's life during the service interval?

 

[Shannow]

Jett Rink, thanks for that, it's interesting.

I don't think mine works that way...don't think it works at all actually