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Discussion Starter #1
Hi everyone. I've had a '94 Thunderbird n/a V6 since August of 2002. It's been my daily driver and has been an excellent car. I've taken good car of it over the years, changed the oil and transmission fluid myself, put on some higher end brakes, and made a couple of mild mods here and there. A good deal of stuff I've learned about my car came from this website but one thing I've always wondered about is the 3.8L V6 and its head gasket issue that people run into. I've even heard about this issue first hand when my cousin's head gasket blew in his Mustang several years ago. My question is does a head gasket failure have to occur? I imagine it's possible that the previous owner of my car addressed the issue long before I ever came across the car but what if this isn't the case? What sets off a head gasket failure? The car has almost exactly 140,000 miles on it from about the 118,000 it had when I first got it 4 1/2 years ago. I don't drive the car very hard and I regularly use a synthetic 10W-30, usually Mobil One.
 

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I don't think it HAS to happen, but it is more possible to happen on these engines than some others. It is a weak link for some reason. I know that there were aluminum head engines before this one, but I think it is due to the HG material not being up for the movement between aluminum head and cast iron block and the different expand and contract rates.

I don't think mine just "went", I think mine was brought on by the overflow tube coming off, dumping coolant on the ground and not having any to siphon back in, and eventually overheating causing it.

I think if you take care of the cooling system then it is possible that it won't happen. I also barely got 130,000 miles out of a couple of 302s and a 255, when I did the HG on my 89 at near that mileage the cylinder walls looked good, and if I was smart I would have done the valve seals, because I see nothing killing this engine but neglect and abuse, and I abuse it and am starting to neglect it.
 

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You have two different metals that heat up and cool down at different times which causes some warping in the head. The heads on the older V6's (like your 94) where not designed that well and are prone to some warping that allows the head gasket to become damaged.

I just did mine at a cost of about $250 for parts ($50) and the have the heads plained ($200). What they told me (cause the heads looked good and the gaskets looked good) was that someone pulled the heads and ground them down with a grinder or something and they had waves in the head, this caused the leakage.

While I was at it, I replaced the motor mounts as well. When I pulled the passenger side off it fell apart in my hands.

BTW: You are lucky to have gone past 140k before it happened. Mine had about 100k when it started getting worse. I always smelled coolant but thought it was the radiator or hoses.
 

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Discussion Starter #4
Thanks. These are basically the kind of answers I was looking for. I already had a general idea of why HG failures occur in regards to the materials used in the engine and heat, but I guess I was wondering what would be going on that's making the HG stay intact. The only major things I've done with the cooling system since owning the car is replace the radiator and thermostat, which I did before the end of 2002, and install a B&M transmission cooler a couple years ago. The line from the transmission runs through the radiator first, exits into the transmission cooler, and then goes back to the transmission from the cooler. I replaced my radiator because there were cracks in one of the tanks caused by heat and I figured it'd be less hassle to just replace the whole thing rather than try and repair the tank.
 

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I've got to get a tranny cooler in mine.

MN12Fan, If and when you do the heads, take them in to a machine shop to have the vatted and tested for levelness (?). That only costs about $70 for both heads. The vatting cleans out the valves, valve stems and all the ports. They also will check to see if any of the valves are in need of attention. I had one exhaust valve that was sticking and not closing all the way (you could hear it tapping real loud). They fixed that too. Anyway, new heads are about $200 a peice. Good luck.
 

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No! It has to happen! You're going against everything that the Ford 3.8L engine stands for! You're going against the system man! Do you want to be the one who goes against the entire system? Now go out there and blow yer dang head gaskets! ;) (KNOCK ON WOOD)
 

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Discussion Starter #8
I would just make sure that the cooling system is clean at all times.

Also don't overheat the motor.
Sounds good. Usually when I drive, even at highway speeds, the needle on my temperature gauge doesn't usually go past slightly left-of-center when everything's warmed up. It has to be a really warm day and/or I have to be driving faster (80+) to get it to move further right. The worst I've ever seen it was last summer when the needle moved past the M in "Norm" on a 105* day going uphill at 70MPH for about 20 miles. Everything survived but I don't want to try that again, not on such a hot day.
 

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When the head gaskets do blow, you should probably replace the O2 sensors at the same time. Coolant ruins them. Also, make sure you use O2-sensor-safe RTV sealants throughout the job (the wrong type also ruins them). Also, there is no better time to replace motor mounts, steering rag joint, or power steering hoses, or to clean and repaint any areas in the engine bay.
 

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Part of what you have to remember about ALL car forums is that a large percentage of the visitors are only there because they have a problem. You get an issue like the 3.8 headgasket, which certainly has a higher-than-average failure rate, and it gets amplified by a few orders of magnitude by a site like this.

With that said, I think Justin hit it on the head. The gasket fails where the coolant passages are very close to the fire ring of the gasket. Keep your cooling system in good shape so that you can keep as much gasket material from eroding as possible, and don't get the motor too hot.
 

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You get an issue like the 3.8 headgasket, which certainly has a higher-than-average failure rate, and it gets amplified by a few orders of magnitude by a site like this.
Actully, the head gaskets on the 94 3.8l were a factory recall. A known problem by Ford.
 

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Actully, the head gaskets on the 94 3.8l were a factory recall. A known problem by Ford.
Yeah, due to a higher-than-average failure rate. My point was, it doesn't happen to every car. It was happening often enough where Ford had to issue that recall to avoid lawsuits and bad press, but it doesn't happen to every car.
 

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Discussion Starter #14
Actully, the head gaskets on the 94 3.8l were a factory recall. A known problem by Ford.
So does this mean that any potential issue with my engine specifically may have already been addressed? That'd be great but I suppose there's no easy way to verify it.
 

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man i wish mine had 140k miles and no HG problem. heck i kept my car in meticulous care and it popped the HG at 59k miles. New longblock later good as new :) lol
 

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So does this mean that any potential issue with my engine specifically may have already been addressed? That'd be great but I suppose there's no easy way to verify it.

You should be able to take it to a ford dealership, they can run the VIN on it and tell you exactly what recalls have been done to the vehicle.
 

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Discussion Starter #18
I have my VIN memorized. I went to the Ford website and it brought up my car but it says there are no recalls listed. I don't why I didn't think of it before but I also went to this NHTSA website:

http://www-odi.nhtsa.dot.gov/cars/problems/recalls/recallsearch.cfm

You can look up recalls on vehicles from virtually any major maker from the past several decades. Anyway, I looked up the Thunderbird for my year and nothing's listed. There is a complaints section though with about 50 different things. HG failure is among them and one guy says Ford "recalled" them. Must have been voluntary or not considered to be threat to safety. A TSB in actuality, perhaps?
 

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I looked in my 95 Ford CD and did not appear to have the TSB's all though another dual CD that I have for the 96 Ford does. I guess you could download it and try.
 
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