Longest OCI's without a filter change

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Apr 4, 2016
10,000 miles seems to be the average "long" duration OCI I see in the UOA section. Does anyone here regularly do 20,000 miles or more without an oil change? If so, what oil/vehicle? How does it look coming out? UOA report? Noticeable sludge/varnish? I'm wondering if there is a trend in what oil brands can regularly do 20k+. Let's see who wins!
I did a few "longer" OCI's without any problems and I used a fram ultra filter for 20,000 miles with no complaints. Now the car has 200,000 miles on it and it appears to suffer from blow-by which puts carbon deposits in the oil and filter so I change the oil at around 7 - 9,000 miles. Mostly I use a combination of cheap store brand synthetic and conventional oil available at Canadian Tire.
Back in the early 90's I ran a Motorcraft FL-1A oil filter for about 30,000 miles over 3 oil changes (15W-40) in a 1978 Ford F250. I had a old Chevy 283 that burned a quart of oil every 100 miles or so, and I never changed the oil filter ever, in almost a decade. During the huge "dot.com boom" in the 90's a fellow I know who was setting computers and servers up for businesses ran his K1500 Chevy 350 ('93 or 94 model) for 50,000 miles on Mobil 1 and a PF35 oil filter (mostly highway miles) and it "seemed" to be just fine, but I don't know what shape the engine was in at 150,000+ because he traded it off with 90,000 or so on it (and it was still running great)
46k on a Focus with the factory filter; then the engine puked. some friends bought the used car at a used car lot. I offerred to look it over in advance; they didn't see the need because it "looked clean". next day on the way back to school the motor roached. THEN I got to see the OEM filter. all rusty on the outside. nice. of course, you are likely looking for success stories... I would imagine, on a non-sludging engine, that 20k should not be a problem .
I'd think it depends more on the filter size and media than mileage. Engine history will be an important part. I don't think you'd ever find somebody with a brain to run a filter for 20k on a VW 1.8... My Fusion returns really consistent UOAs and I always change the filter with the oil change on it. Last UOA I have the results for was almost 14k on a Napa Platinum; awaiting results on the Napa Platinum on a 17.3k run. So far, my insolubles have always been 0.3 (except for two 0.4s on Amsoil EaO34 filters with shorter mileage) and I think that is what should be driving your filter change. From what I understand, a filter "should" trap more of the insolubles up to the point that the media is saturated and you drive the filter into bypass mode because of the differential pressure across the media. After that, your insolubles would likely start to go up maybe not exponentially, but certainly much faster than if you were filtering it. This OCI I have a Microgreen on it, so we will see if the insolubles come down any due to the 'bypass' element in the MG.
Originally Posted By: 1JZ_E46
Originally Posted By: Vern_in_IL
Kendall and an Ultra All THE WAY!
I simply forgot to change the oil, I do 8k oil changes and skipped one, and it was last winter.
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