Is there a difference between the under the flip top cap made for California cars ( Challenger R/T) and that for other parts of the U.S.? I have what I thought was the basic screw on cap for under my flip top. I can get it on but it needs to be encoraged to come off. This is not the locking cap just the turn on.
Is there a differnce between the R/T,base,TA?