I've voiced my opinion about the oil change warning system before. Some people have called me an idiot but I have tested this thing pretty well over the three years that I have owned the truck. It should be noted that I drove it the first winter but have stored it each winter since. So, aside from that first winter all the driving has been summer with half or more of the KMs accumulated with our 8,000 # travel trailer on the hitch and 1,000# in the box. The truck now has 110,000+ KMs on the clock.
Because of our summer activities, much of the driving with the trailer involved many trips up and down the same roads. All city driving was done with the transmission set using only 1 to 4 gears and the truck is always driven with the engine brake on. Enough back ground.
There is no rhyme nor reason to when the oil change signal comes on. I have had it tell me to change the oil at intervals ranging anywhere from 800 KMs to 9,800 KMs. I finally learned to ignore it. I change the oil and filter, every 10,000 KMs, along with a chassis lube. Because of availability and price, I recently switched from Mobil Delvac 1 to Amsoil Premium CJ-4 and always use Fleetguard filters. The truck has never used oil nor does it "make" oil.
I hope this all helps.

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2007 Ram 2500 QC 4x4 SLT TRX4-Offroad 6.7L Automatic. '08 Jeep WK 3.0L diesel-wife's DD.
1998 Jeep ZJ 4.0L Automatic Selectrac-project for our son. '98 Jeep XJ-my wife's former DD.
1965 Dodge Polara 880 Convertible 383 Automatic.