2006 Subaru Tribeca Radiator Broken During Accident

Reader Question: Hi,

I really hope you can answer his for me and get me out of trouble with my husband. I am not a complete idiot, I actually know some about cars as I used to work on muscle cars (fixing them when they broke down) in my teenage years.

My high school boyfriend actually put transmission fluid in the brake fluid once so I am well aware of the implications of wrong fluid/wrong place.

Here is my problem:

Accidentally, I hit my car my 2006 Subaru Tribeca (14,000 miles) with a deer in early February 2007. It did some damage (mostly cosmetic) but was drivable. After the cop shot the deer, I drove to the nearest gas station and inquired if there was a mechanic nearby that could check the car since I just hit a deer – there was none.

The radiator was hissing a little and there was a drip or two of radiator fluid but nothing major. I bought the radiator sealant (Prestone Stop Leak I think) and added that as well as Radiator fluid to the radiator reservoir of my car.

I checked the driver’s manual first before adding anything and to determine the precise location of the radiator cap/reservoir and how to add fluids prior to doing so, since I had never even popped the hood before.

My friend also read and verified that we were doing it right for this car. I even waited for the engine to cool even though it said I did not have to (mind you it was 10 degrees out no less).

I added the Sealant per the instructions on the bottle and added some extra radiator fluid. I watched the engine while driving to make sure it did not overheat and there never appeared to be an issue since – no hissing, no leaking so I figured to wait until the insurance company fixed it.

The auto insurance company inspected the car the week after the accident and the auto body place took the car on March 18. The insurance guy told me to drive it until the auto body shop could take it since it was still drivable. I was not allowed to leave it as they didn’t consider mine an emergency.

Upon further inspection the auto body and insurance company said that there is some sort of gunk all throughout the engine and it was “pretty bad and they have never seen anything like that before” and that I would have to replace the engine and this is not covered under insurance.

They actually flat bedded the car from the auto body to the dealer today for further inspection. I experienced no problems with driving it at all after deer. Pick up fine, mileage fine, no weird sounds, or anything. It ran quite well.

What could this gunk be? Should I have flushed the radiator when I got home – it said it was safe and I never did before? I swear I put the right stuff in the right reservoir but could the Prestone stuff gotten through to the engine and messed it up? Could someone at Expressway Oil/Lube accidentally put something in the oil reservoir or the radiator that would cause this? If so, what?

Perhaps someone added washer fluid to the radiator since it looks remarkably similar. I actually double-checked. Could the oil change place not have changed the oil and left old stuff in there?

In any event, I am stuck probably paying for a new engine but perhaps my husband would stop yelling at me if I could have some plausible scenarios, which I obviously do not have.

I am in a quandary over what could possibly have caused this mess.
Please help me.

Thank you in advance,


Hey Sonja,

Austin: So they want to replace the engine just because of this “gunk”?
Sonja: Yes.
Austin: I would not replace it just because of that.

Austin: It runs ok, not overheating, not making noise, not using engine oil, etc. etc. etc. all the common signs of needing engine replacement?
Sonja: I experienced no issues.
Austin: So, don’t replace it

Austin: Using stop leak in a radiator is a last ditch resort when there are no other options. I would assume the stop leak additive produced the gunk they see.

Sonja: They are saying that they think it is that. I added it because when I got to a gas station there was a small hiss coming from the radiator and a few drops of fluid. It was 10 degrees and late at night in the boonies of NY/VT with at least an hour drive ahead and a 4.5-hour drive home.

Austin: Stop leak is not going to repair a cracked radiator, it will stop or slow down a leak in a seal or gasket but not correct something broken from a wreck, call a tow truck, and your auto insurance would have paid for it.

Austin: There could be engine oil cooler or an automatic transmission cooler inside your radiator and that internal cooler could have broken on impact so your engine oil or transmission fluid leaked into your coolant and produced this gunk.

Sonja: I am wondering that or it maybe even a seal or something burst as we ran her over a little as well. The car does have a weird automatic/shift type of transmission that they call “sport shift manual control”

Austin: I am not very familiar with your vehicle, but if I were you, I would call or visit your local Subaru parts department and ask them if your radiator is equipped with this option.

Sonja: The dealer is evaluating the issue.

Austin: Talk to the parts department guys about this….”does my radiator have an internal engine or transmission cooler” “could this gunk be from oil or transmission fluid that has mixed with my coolant because the cooler broke during the wreck”.

Austin: If it does have this option, I would contact your insurance company and tell them what you have found, and that since the cooler is inside the broken
radiator this gunk is a direct cause of the accident.

Sonja: Interesting, the insurance company claim adjuster actually told me it was drivable and to continue to do so until their auto body place could take it in to be fixed.

Austin: So you are encouraging you to drive a car that they claim needs a new engine. It sounds stupid to me. You can take the car anywhere to get repaired. You saved your insurance company a huge tow bill from the middle of nowhere.

Make sure these guys know that. Squeaky wheel gets the grease you are not squeaking loud enough. I would get your insurance to pay to flush out the cooling system since you added the stop leak to get off the road and back home, saving your insurance company money!

Austin: However, on a side note, if you are not experiencing any of the issues I first mentioned, I would have the visible repair work done on the car, new radiator etc. etc.

Then take the care to a fast lube place and have them flush out your cooling system with their flushing machine. If they do not have a cooling system flush machine, find a place that does. You want to run as much clean coolant through your engine as you possibly can to remove the stop leak additive.

Sonja: OK, I will have that done as well.

Austin: But as far as replacing the engine at your expense…you have not convinced me you need to do that.

Sonja: Thank you for the advice.

Austin: Welcome!

Austin Davis

Posted in: Reader Questions

Got Something to Say?