joelmd

hello. i have a '96 gt auto convertible and i recently checked the radiator and the "water" was a coffee brown color with a sheen to it. everything i read on the internet points to the intake/head gaskets. i have never had issues with overheating so i am not sure what could have caused the problem.

also, the car was not overheated when i checked it. i checked the oil (via dipstick level marking) and it looked normal. no sign of water, the oil is a little dark but based on my records i had not reached the 3000 mile mark since my last change and the car does not seem to run ok. i noticed a drop in power. i got home and the next morning when i checked the water level i noticed the problem in the radiator. i did not notice any white smoke from the exhaust that morning i check it.

I also spoke to the mechanic who has done most all of the work on my car the past 4 years. From experience he said it is extremely rare for a 4.6L to blow a head gasket. He also said intake manifold leaks are not uncommon, but if an intake is leaking on that car it cannot mix oil and coolant.

i described this to another mechanic and he said it could also be the oil cooler. not a transimission oil cooler but engine oil cooler. i try to be informed of my car but i am not familliar with an engne oil cooler on it. doess it really have one? the car is stock and i can't find any documenation on the internet to it.

Obviously, further in person diagnosis is required but can anyone confirm who is on the right track? it is expensive to have the car towed back and forth just for estimates. how much would you think to repair?

i have 153K miles on it and everything else on the car functions so i need to decide if it is worth repairing

i have already flushed twice, drove it about 10 miles and checked it. i was the same, brown, frothy, and oily result. any other thoughts?

thanks for any input.

WhiteFoxGT

Well, Im goin to try to give you some quick answers without goin into paragraphs..

Oil + Coolant can happen a couple ways. The trans fluid in the rad could me mixing slightly with your coolant (both coolers are one unit). The oil cooler is the piece behind your oil filter, and it could be mixing the two. Or like you have stated, head gasket. Best thing to do is take it to one reputable shop you trust and have them diagnose it for you. Get the coolant tested for hydrocarbons and it will tell you if there is combustion in there (head gasket)

I could go on and on, but I dont really feel like typing. My scrapple is cooking at the moment.

pcs

you could also just do a compression test, you can rent the tool at autozone for free if you dont have one to check for leaks, that can tell you if you have a blown head gasket. the brown shade in the water could just be a form of iron oxide, due to the age of the radiator. the oil could have come from your tranny cooler like whitefox stated. you could also check your plugs to see if you are burning oil or coolant in the cylinder. and yes the plastic intakes on early 4.6 engines are know to crack and leak.

joelmd

thanks for the input.

ym42

Coffee brown color is NORMAL! Why do you think there is anything wrong with it? Old coolant, especially Dexcool type, turns brown after a couple of years, especially in expansion bottle...

ym42

Sorry, you can disregard my previous post, did not know how to delete... I did not see the end of the original message, where it said it was flushed already... Dont know...

WhiteFoxGT

And Im not just gonna dis-regard this either. Dexcool should not be anywhere near a Mustang. And brown coolant is a sign of rust. If your coolant is brown like the TS says his is, then its not something you should consider normal deterioration of coolant.

joelmd

thanks for all the input. seems the problem was the oil cooler. had it replaced and have not had a problem since.