All the seven 940s in the family (4 people) use Mobil 1 and I change the oil every 10K miles and the Mann filters every 5K miles. I have been doing this for years with good results.

I have a 94' 940 with 88,100 miles that we only drive in the Summer to keep the salt off here in MN. We are retired and don't drive much and we have another beater 940 we also drive in the Summer. The last time I changed oil in this car (the one with 88,100 miles) was 2012 and it has 7K miles on the oil. Should the oil be changed because it has been 3 years since the last oil change or is it okay to wait until the Mobil 1 has 10K miles on it?

Thanks
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Mine: 3-940s running, 2-740 and 1-940 parts cars, and 3 1959 John Deere 630s (1 parts), dtr1:3-940s, dtr2:1-740, 1=940

I changed the Mobil 1 oil yesterday just to be safe. It was in for 3 years and looked good but I didn't want to bother with an oil test. I think I will stick with the 10K oil change and 5K filter change routine but also go no longer than 2 years. The car is not short tripped and always gets up to temp. when driven.
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Mine: 3-940s running, 2-740 and 1-940 parts cars, and 3 1959 John Deere 630s (1 parts), dtr1:3-940s, dtr2:1-740, 1=940

I was told, with mobil-1, one year is safe after I posted the same question but I seem to extend it to two years once in a while. If you get the engine hot and evaporate all the moisture in the crankcase it would be safer for two years but this is just an opinion. Need a oil test to confirm.

Tom

I have gone at least 3 years on oil without negative results. I think it'd depend on how clean the oil is, free of contaminants like fuel and such...

you have 7 940's and decades of experience and you're asking us?

Tritchard, actually 7 940s, 1 740 running. Two 740s and 1 940 for parts but that doesn't make me an expert on oil changes and what is safe.
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Mine: 3-940s running, 2-740 and 1-940 parts cars, and 3 1959 John Deere 630s (1 parts), dtr1:3-940s, dtr2:1-740, 1=940