Stant Radiator Cap, Part No. 10263? Its supposed to be an OEM equivalent replacement, but after a week or 2, it seperated into 2 parts. The cap seperated from the threaded part. I have a new one coming tomorrow as a replacement, but wanted to know if anyone else was running one of these without issue, and for how long? Next to my OEM cap, they looked identical, but sadly after running the new one for a couple weeks, I just threw the old one out yesterday

 

NEVER throw out the old part until satisfied the replacement is good...

I changed mine when I did the cooling system last fall with an OEM part from Jag. I've never had good luck with the OTS parts from AutoPepZone; sometimes, even though it may be a few ducats more, the OEM stuff is the right way to go, especially on critical systems.

Not criticizing, mind you, just sharing my experience.