So after many times seeing various members posting about their OEM radiator caps falling apart within the housing, I FINALLY took the time to order one (Gates brand, instead of OEM). Found mine, like many of yours, totally in pieces (3 to be exact) just sitting inside the housing. Replaced it with the Gates branded cap, and all is well. No pieces were MIA, as some other members had posted about. Got lucky I guess.

I created this thread to get a sense of really how many other members that have either already experienced this issue and replaced their caps, know their caps are faulty and need to replace them, OR need to check to see if theirs is indeed faulty.

***Top tip, when checking your radiator cap, it is best to check it when the motor is cold.***

Please log whether your OEM radiator cap is faulty within the poll function, and post below what model year 2IS you have, AND what brand radiator cap you replaced it with.

2006 IS350
Gates cap

 

I changed the OEM cap for another OEM. It was probably at around 75K or so. As far as I can tell it was the OEM with no issues.

 

I'm still on my original cap @ 170k. The only thing I've gone through so far is overflow tank caps in an attempt to fix its inherent leaking nature.

 

my 2nd rad cap on my IS

 

At 60,330K miles, my 2010 IS350 still has the original cap, although I do have a new OEM sitting in the package. I will probably change it out at 100K unless the current one goes bad. I still have the original radiator caps on my 2006 Camry SE (3.3L V6) @155K plus and on my 2013 Toyota Sienna @140K plus

 

I started a whole thread about my issue, but basically I had the OEM cap on my 06 is350 with 122k miles when I chnaged it. I checked it when it was cold and while turning it made a cracking sound that I never heard before then... blamo!! It broke apart technically in three peices. Replaced with a new oem cap..

 

I just picked up a Blitz one today so technically it is my 3rd cap instead of what I said in the earlier post, might as well replace everything when I am gonna put in new rad, water pump, and hose

 

2008 IS250. Roughly 135k miles when OEM cap failed. I replaced it with another OEM. I noticed the radiator had a very small leak at the same time.

 

the small leak I had was on top of the rad probably started 2 years ago, just never had time and money to go fix it, finally gathered all the parts (rad, water pump, cap and HPS silicone hose) to replaced everything yesterday but it was too late, it f-cked up the A/C pump too now have to dump more money to get that replaced lol...

 

I have an '08 IS350 and the cap was found to be broken around 100K IIRC. Replaced it with an OEM cap.

 

Looks nice. I ended up buying a oem denso radiator from rockauto for ~$100 shipped and replaced. Fortunately, I had some oem antifreeze already so it didn't cost much to repair on my car. I also replaced the thermostat with an oem aisin for ~$40. The radiator cap was more of a shocker at $17 for oem. The radiator cap and thermostat are really 100k mile replacement parts. I got lazy trying to see if they would make it to 150k. 150k is when the owners manual calls for a coolant change. I was going to do everything at once... which was still the case.

 

I replaced my thermostat and the belt last year... same here I got all the oem parts from rockauto...

 

hey guys. also had the radiator cap all broke ×}=¤/¤! lucky I got all the small pieces out..? is the resevoir cap also a weak point and should be replaced? dealer said resevoir was a little low...all these little headaches omg

 

I replaced mine with a new one shortly after I bought it

 

check my thread about it, I ended up loosing coolant from a upper rad hose and wouldve never found out until the cap broke on mine. Bleed the system from air afterwards I had a good amount since I was low on coolant and I had the water rushing sound in the cabin.