1998 f-150 with the 5.4 I have been having this problem off and on for several years now. Back in June of 2006 had the truck in for a leaking radiator. It was leaking where the core and the plastic ends meet. Radiator was replaced and flushed the whole nine yards everything great back down the road. Then Mach of 07 bam radiator is leaking again same place. Took it back to the same shop (a reputable shop) and they replace under warranty no biggie back down the road. Now again in Jan of 2008 same problem same fix. Then again in March of 2009 same problem same fix, and again then again in Sept of 2009, and again one year to the day in September of 2010. Now I am really not to bent out of shape about it because it has been fixed under warranty every time and not a dime out of my pocket, but it does kind of get annoying loosing the truck for a day every year. This is my personal truck so I am the only one that every drives it. It does tow alot but its in immaculate shape and has never been wrecked. Anyone ever heard of this or had a similar situation???

sounds like the shop dont know what they are doing... now mind you i have no experience with this shop... just sounds this way.... I would ask them to replace it with a brand new radiator again..

could also be something else.... do you lose some anti-freeze fluid now and then? why I'm saying this is mine is a 2000, 5.4, and it does leak a little ( which I heard is bad for these motors ) in the headgasket,, why I'm bringing this up, is I had a similar issue you had with a older cougar, which the radiator leaked and replaced, the new one did as well, found out later, that the headgasket blew, and the backpressure come back through the cooling system from the leak and blew it out...

I don't know of a way to check the pressue of the cooling system with the engine running?

I also agree, they do not make the radiators like they use to... ( lots of plastic ) so you may also be getting bad parts..

nflfreak43 said:

sounds like the shop dont know what they are doing...

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Unless they built the radiator how would they not know what they are doing? Maybe like stated there is some other underlying issue causing his radiator to go bad. That's kind of jumping the gun on blaming the people who installed it. Opinions like that is what causes the general public to just blame every mechanic/technician as being bad.

I won't claim to know much about these sorts of things, but it would seem two possibilities would be that either the radiator is being flexed in such a way that it's weakening and leaking over time (which seems unlikely) or there's getting to be too much pressure in the cooling system.

I'm thinking that truck's cooling system is of the design where the radiator cap is on top of the coolant bottle...and, to be honest, I haven't a clue how those work. But perhaps there's some component in there that's supposed to bleed off pressure but isn't, in your truck? Or, as stated above, a head-gasket leak allowing combustion gasses into the coolant.

73F100Shortbed said:

Unless they built the radiator how would they not know what they are doing? Maybe like stated there is some other underlying issue causing his radiator to go bad. That's kind of jumping the gun on blaming the people who installed it. Opinions like that is what causes the general public to just blame every mechanic/technician as being bad.

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well also at the same time, if this kept happening wouldnt a "good" tech investigate why its happening? i know i would.

and i was purely saying if they were repairing the radiator and it kept having the same issue its possibly a repair issue, now as to whether that was happening i couldnt gather from the OP.

and yeah theres quite possibly an underlying issue. but from my experience, if ya have a head gasket leaking and a rad leaking, putting a fresh radiator in will up the pressure causing the Head Gasket to blow the rest of the way... IE: my Flareside..

nflfreak43 said:

well also at the same time, if this kept happening wouldnt a "good" tech investigate why its happening? i know i would.

and yeah theres quite possibly an underlying issue. but from my experience, if ya have a head gasket leaking and a rad leaking, putting a fresh radiator in will up the pressure causing the Head Gasket to blow the rest of the way... IE: my Flareside..

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Which you should have known would have happened before you did it

I think the radiator was replaced every time if I'm reading his post right.

I keep a pretty close eye on it and it has never leaked any coolant. I have never had to put a drop in until it starts leaking.

I'm pretty confident in the shop that it has been to, they have wokred on a few on my other trucks with out problem. They are strictly a radiator shop, thats all they do and thye have been in business for over 30 years.

john112deere said:

I won't claim to know much about these sorts of things, but it would seem two possibilities would be that either the radiator is being flexed in such a way that it's weakening and leaking over time (which seems unlikely) or there's getting to be too much pressure in the cooling system.

I'm thinking that truck's cooling system is of the design where the radiator cap is on top of the coolant bottle...and, to be honest, I haven't a clue how those work. But perhaps there's some component in there that's supposed to bleed off pressure but isn't, in your truck? Or, as stated above, a head-gasket leak allowing combustion gasses into the coolant.

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I kinda of thought that for a while maybe the frame was tweaked a little in the front causeing it to flex the radiator, but had the front end checked out and it is straight as can be. He also tried putting in different rubber grumets in the front and trying different spacing to ensure it was not flexing.

Yes it is the style with the cap ontop of the bottle.

73F100Shortbed said:

Which you should have known would have happened before you did it

I think the radiator was replaced every time if I'm reading his post right.

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Yes I guess I am really not complaining just sharing an interesting stroy and seeing what everyone elses thought on the issue were. Yes the radiator has been reaplaced 6 times and I have not been charged a dime since the first time. Almost kinda feel bad for the guy I bet he didnt make a dime on that install.

I looked at all tsbs and special service messages, and theres nothing from Ford for this concern. It would be usual diagnostic techniques to find whats happening.

I'm digging this one back up again. I was hoping I was done with this problem. Got out of the truck this morning and noticed a quater sized puddle under the front driver side corner. Shoot......... it happend again the exact same place. I get back to the shop this afternoon and pull the plastice cowling off of the top of the motor. Last year when this happend I wrote all of the dated down in sharpie on the top of the new raidatior. Now mind you this is raidator number 7 in 6 years. The dates for the last few years are as follows 9-27-11 (today), 9-30-10, 10-1-09, 8-15-08, 9-10-07, 9-15-06, 3-22-06. I found that pretty damn interesting the last three years the radiator has gone out with in 4 days of being exactly one year. Just about to drive me mad.........

Krafty,

Sucks this is happening to ya. If it helps any I have had my MOTOR out more times! LMAO

Anyway, can you get some pics of where it is happening, I have noticed that on that side of the radiator when installing/removing it that the Trans lines that run into it have a tendancy to spin a bit. Might be giving the pressure in the radiator to bypass the lines. May not, just an oservation on my part.

lil_dq said:

Krafty,

Sucks this is happening to ya. If it helps any I have had my MOTOR out more times! LMAO

Anyway, can you get some pics of where it is happening, I have noticed that on that side of the radiator when installing/removing it that the Trans lines that run into it have a tendancy to spin a bit. Might be giving the pressure in the radiator to bypass the lines. May not, just an oservation on my part.

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Hahah well at least this is a little easier to pull then the motor. I will get some pics when I get it back. It looks to me like it is leaking right where the plastic end meets the core on the pass. side. I dropped it off at the shop last night, to get a new one put in. The guy is very good about sticking behind his warranty, I almost feel a little bad for him this being the eighth one he has put in. Just wish I could get this figured out. I would think after this many times he would try and get a rep from the radiator company out to take a look.

One look at your pickup and you can see that you don't beat the snot out of it....It's got that cared for look.

At the risk of sounding more stupid than I am, something is stressing your radiator-s-s-s-s-s-s-s-s-s (is that 8?). One, maybe two could be defective.....but not eight. So the obvious (to me) possible causes would be, improper mounting/installation or excessive pressure (head gasket?) (defective pressure cap?) Are the replacement radiators-s-s-s-s-s-s-s-s OEM or aftermarket and if the latter, a reputable brand?

Well go the truck back today, wasn't really able to look at it too much since it was dark out. Not sure on the what is causing it. I wouldn't think it would be a head gasket, I am not losing any coolant. The guy did mention that the rubber mounts looked really smashed. He said he put some silicone lube on it and to check that reguraly. I'm kind of hoping this doesn't happend but I know that is just wishful thinking.

What the hay? I thought I was the only one with this problem. My truck is a 2000 f250 superduty with 5.4. The original radiator lasted for 10 years, since then I have replaced it, today will be 6 times. Same as you they have all been under warranty. But it is very aggravating!!! I can remove my radiator in 9 minutes. The leaks are where the it is crimped together, mine is on the driver side. After all the taking out and putting in, Im thinking that maybe I am tightening down too much. Its almost like its squashed..