Aftermarket vs OEM Radiator Cap, Question of stress on radiator

Looked around about the topic but could not find anything.

My question is in regards to stock and aftermarket radiator caps ,and the different levels of PSI that they have. I noticed that the aftermarket radiator caps have a higher PSI than stock. My concern is the fact that the radiator on my car is maybe the original radiator that came with the car ,but it is very old. Otherwise, it is fine with no leaks so far. Would the higher level of PSI stress the radiator more and increase the chance of failure with the radiator? Thanks.

well it depends if you have the full metal rad or the other with plastic. the reason after market rads have higher psi is that theyre all made of aluminum or some other metal so they take more pressure. Our oem plastic rads cant take the same psi on a daily basis so a good rule is to stick with stock equipment. If you upgrade to a full aluminum rad it usually comes with its own spec cap…

I know from experience not to mix aftermarket rad caps on a oem rads… I had a mishimoto rad then sold it and swaped my old plastic rad back with the mishimoto cap, weeks later came home and shut off the engine when I hear a loud pop and steam vents up. turned out to be the lower rad endcap popped its seal and shoot water out 12 feet infront of the car through the grill… Had i have the stock lower psi cap pressure would of transfer to the overflow tank…

[QUOTE=da6xsi06;2212006]well it depends if you have the full metal rad or the other with plastic. the reason after market rads have higher psi is that theyre all made of aluminum or some other metal so they take more pressure. Our oem plastic rads cant take the same psi on a daily basis so a good rule is to stick with stock equipment. If you upgrade to a full aluminum rad it usually comes with its own spec cap…

I know from experience not to mix aftermarket rad caps on a oem rads… I had a mishimoto rad then sold it and swaped my old plastic rad back with the mishimoto cap, weeks later came home and shut off the engine when I hear a loud pop and steam vents up. turned out to be the lower rad endcap popped its seal and shoot water out 12 feet infront of the car through the grill… Had i have the stock lower psi cap pressure would of transfer to the overflow tank…[/QUOTE]

thanks for the info. makes sense considering my stock radiator has plastic. I wouldnt think it would take the pressure well especially considering my radiator, I think, is the orignal that came with the car.