wally world carries 5 qts jugs of Mobil1 0W40 and Castrol 0W40 for lower cost than others.

sometimes I find lower cost deals on oils like Kendall Euro etc and buy a case. I go a lot of miles on one oil charge - about 11,000 - you can change it earlier if you want.

I have also used Delo 400LE 5w40 in this engine with no issues (didnt have the dry startup noise with it)

Always buy a fleece type filter for the engine, its specified for later models but fits in this one too, also available as a purolator part (same german filter in different box)

It is also necessary to make sure the entire breather system on the engine is in top shape - there are no PCV valves but there are two chambers on the valve covers, if they are leaking or blocked your oil will degrade a lot quicker, start sludging and also may cause oil consumption.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)