Oil in radiator but not in engine block

Asked by May 01, 2016 at 09:23 PM

Question type: Maintenance & Repair

Any one know about this 1997 mustang v6
No wight smoke
No oil in block
New moter not long ago
Maybe 30000 miles
Runs smooth and idles fine
Not seeing any leeks
Hoping it's not blown gasket and maybe tranny oil
from tranny cooler
Any one have answers?

11 Answers


If the oil is black then its engine oil, if it is red then it is transmission fluid. One thing does confuse me is you stated no oil in block, do you mean that there is on oil on the dipstick?


Are you saying that the engine oil level is low, and you have oil in your radiator?


And is it an auto or manual?

Best Answer Mark helpful

Automatic Oil is normal no water not low Tranny has problems for a long time now I put special thick oil to stop the sloping in the tranny and it's not red


Ok what I would do is have the cooling system power flushed to make sure this isn't residue from the engine replacement. then just keep a eye on it if the oil returns then you know you have a problem.


The transmission fluid your putting in isn't red? If the oil looks ok, you have an automatic transmission and your getting discoloration in your coolant. It's probably corrosion in your coolant system or if it matches the color of the tranny fluid that your using then your radiator is probably leaking tranny fluid into your coolant. Cooling systems are super simple, there are only a couple things that can go wrong. From your original post you never mentioned any overheating?

That's what I think or hope is the problem I will look at it again and flush it to see if that makes a difference It did over heat but not major Once a long time ago but was ok till now it ran hot the other day that's why I looked and found it low on coolant I filled it and it has not over heated since Maybe thermostat no good maybe it needs to be flushed I will flush the system to see what that gets me. Old car with lots of new stuff I don't want to call it quits yet


When you flush it spend the extra $30 and replace the radiator cap and thermostat. They're super cheap and are the most common things to cause overheating problems. You can test them as well,there are plenty of YouTube videos on that. And spend plent of time working all the air out of the system when you flush it.

I will take it to someone for the flush I forgot to say that the cap river gasket was looking bad Will do thanks

But if the oil comes back I need help trying to figure out where it's coming from And if it's a bad head gasket or tranny oil I hope i just need a new radiator and not a head gasket job that's more then I can aford


Start with the simple things first. Switch the cap and thermostat, flush the system and check the coolant color and oil dipstick to see if anything is crossing over after it runs for a bit. If it over heats, stop the car and turn it off. Don't make things worse. If it is crossing over then it is a head gasket.

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