[afnan]

Hi,
I have 3.0 2012 CRD and have noticed small deposits of oil in the expansion tank. I believe it is because of the oil cooler. Engine oil is still jet black so it means that it has not made its way to the engine yet.

I need your valuable suggestion on the approach to fix it.

Approach-1

Buy a cooler assembly along with oil filter housing and install it

Part costs 1650$
Labour quoted: 5 hours
Plus oil and coolant

Approach-2
Just buy a cooler and replace it while the housing is still mounted on the engine. The mechanic says to replace the entire housing so that there are no future leaks in the oil filter assembly.

Parts cost 350$
No cost for labour but I believe should be an hour or so.

Approach-3
Buy cooler and all gaskets and remove the cooler and filter housing and dismantle it and install new gaskets
Parts cost: 350$
Labour quoted: 5 hours

What do you guys recommend ? am I alright just to go with approach-2 and still have peace of mind??