Jim Grant's Tech Tips
‘00 Ford Explorer, Old, Oily Coolant
I'm close to buying a ‘00 Ford Explorer V8, with 73,000 miles. The fluid in the radiator overflow container is more brown than green and has an oily appearance on the surface. Is this of major concern or just in need of a radiator flush? …
Clearly, the cooling system has not been correctly maintained. A cooling system flush is in order but I do have a concern regarding the oily appearance that seems to be floating on the coolant in the reservoir. The oil residue could be the remains of a coolant additive, poorly handled coolant during service or even a more serous issue, automatic transmission fluid. The automatic transmission oil cooler is built into the radiator of this vehicle. It doesn’t happen a lot, but the cooler can fracture and transmission oil can enter the cooling system. I would suggest that you have a technician inspect the cooling system. It may be no issue at all, the vehicle only needs to have the cooling system serviced. But, you’d be better off knowing before you lay your money down on a vehicle that may has serious cooling system issues.