Yes.
Blown head gasket will do it check your coolant for oil in it and your engine oil for coolant it it...
Head gasket & oil cooler
Head gasket & oil cooler
it is common for this to be a head gasket but if you do not have oil in the coolant or coolant in the oil i would start with the thermostat. if your engine temp. is higher then normal this would be a good place to start.
Change your oil cooler.
Passenger side front of the engine, near the coolant bottle.
There are two possibilities, one it is most likely the automatic transmission cooler( in the radiator) is leaking transmission fluid. The other, engine is oil entering the cooling system through a leaking headgasket, cracked cylinderhead or engine block.Keep in mind that the engine oil pressure( normally) is allways higher than that of the coolant system , when engine is running.It is rare but possible that engine oil @ say 40 p.s.i. is entering the coolant system, but when the engine is shut off the coolant system pressure is not high enough to leak into the engine oil .It is not uncommon for(in radiator) transmission coolers to leak oil into the coolant system.
No you can not use gas engine oil in diesel engine oil because processing of diesel engine is different from gas engine oil. If you use this then it damage your vehicles.
Normally a sign of a coolant leak in the oil cooler. Replace ASAP.
You've got a leak in your fuel injection system.
NO, do not use diesel oil and a gasoline engine.
Oil is just as important to a diesel engine as it is to a petrol engine