Radiator cap leaking AGAIN!

My truck is 5 years old and the original radiator cap was replaced under warranty because it was leaking and I was loosing fluid. Now.....a 2-3 years later, the replacement cap is leaking again.

What the...??

I really don't want to buy another Toyota cap again and have to replace it in another 2 years.

The stock cap is 13 psi (per another thread).

Any suggestions for a good reliable cap? Or just go and buy whatever the local auto store has in stock? I'm game for anything....

Thanks!!

 

I am sorry that you are having problems with your radiator. I do not know how mechanically able you are, but here is an option. Most autozone and advance auto parts stores have loner tools. One of those tools is a radiator pressure tester, and some come with a adapter to check the radiator cap also.
Since your cap is failing at a early date, you can do this right now. Remove the cap when the motor is cold and look at the bottom of the cap. There should be a rubber gasket on the bottom of the cap. Look for tears in the rubber and move the piece around to see if it stiff. Push on the spring and see if it moves without a lot of force. You may want to look around the filler neck of the radiator to see if it looks cracked or broken. If all is good then the radiator tester will help to see if you have any cracks or broken areas on the radiator.
If your system tests good and you can find no problems with your old cap, then you will need a replacement cap. The best aftermarket cap is a Stant radiator cap. You can get them at a Advance or at a Napa autopart store.
I do not know how old your antifreeze is and what brand it is. I can only relate a problem I had with a GM radiator that was leaking and it had the factory antifreeze in it. GM antifreeze is an organic base to it and if the radiator would be low on fluid, the resulting air inside the radiator would dry out the organic radiator fluid and it would form a brown muck that would form around the neck of the radiator and around the cap. I do not know if the toyota fluid would do the same, but if you see some mucky substance around the cap when you open the cold radiator, it could be making the cap to vent fluid out. If the cap is mucky, you could clean it under water and wash the area of the radiator that is mucky also and replace the cap to see if it will malfunction again. GOOD LUCK.

 

Check your filler neck's sealing area for nicks, cuts and burrs. Theyy can make your cap fail.

 

^^ This.

My old Civic developed leaks around the filler tube and it took me a few radiator caps to finally realize that was the problem. Take your cap over to your local parts store and test it unless you live close enough that the coolant system won't pressurize and then you can try testing the fill tube.

I don't have too much experience with aftermarket radiator caps and I decided to replace mine with the 16.5 PSI TRD cap after I got my S/C. (Wish I could remember where I put the original one)

 

Thanks Gang. The truck only has 45k miles on it. So I'm not worried about the system needing checked. I will check the filler neck more closely this time - as I remember checking it the last time - probably not close enough.

Stant is a good name - I hope my auto store has that brand.

Thanks!

 

Replaced the cap today. The STANT OE replacement cap is 16psi.

Filler neck is fine...although, what the hell...plastic??

Majority of the 'debris' left from the leaking is at the cap, but there might be signs of leakage along the top where the plastic meets the metal. God forbid....

 

Do not forget age of the vehicle- your at 4+ yrs, even if its a new truck things can and do go wrong...

 

I thought I bought a Toyota. Whatever happened to the quality of the past?

 

I know sucks to hear stories on these forums of Toyota quality, but remember as a whole we are a small group of Toyota owners which can magnify things at times

 

I owned a 96 tacoma for 5 years..... So, you could say I'm unfairly judging this 07 againest my 96. Quality just isn't the same anymore.

I Love my truck!! And plan to keep it for another 5 years...!!