Hi guys I am new to the group but have an issue with my 2001 4.6 Ltd 32 v. I replaced oil and filter with no problems then notice small coolant leak coming from oil filter after about 500 miles of driving. Replaced filter with different type and that fixed the leak. Went to top up coolant and notice there is now a thin layer of oil on top of the coolant reservoir. When the wrong filter was fitted would some oil have got into the coolant system? Should I flush the system and add new coolant or will it be ok to continue driving. Thanks for any help.