I am not looking forward to replacing mine either. I am not going to do the job until I see at least one car where it passes the FSM oil cooler T stat test. From studying the T stat on my spare filter housing, my current opinion is that the slow warm up of the oil cooler on my 85 is consistent with how I think it should operate. That's why I want to see a car that operates per the FSM test so I can change my mind.

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked