The analog cockpit version reports the proper oil temperature (the one calculated by REP). The G1000 version, instead, can only report the default internal oil temperature of X-Plane, which is totally useless in REP’s case. This is a known issue.
How-To: Choose the right oil for your engine
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In this post we will talk about mineral oils for our airplane engine. How should you take care of oil with the Reality Expansion Pack?
This is a long topic so we’re gonna walk through a series of questions that will end with the most important: which oil should you choose for your engine?