you probably need to do more antenna tuning .if you get good swr from ch1 thru 38 thats not bad .i dont even get that wide a spread with the amp on but i run much more power .
i just tune the whip for the channel i will be using the most with the amp on .in my case thats ch28 so i set it for that channel with the amp on .
i dont think any wilson will get a great low swr across the whole 40 with a amp running .barefoot yes....
the very first 5000 i had was a good one .i ran a 2by6 thru it for near 5 years ,then a 2by8 for a couple more after that .that coil gave me a good low swr across all 40 .
the coils as of late just havent been as good .
getting them open without trashing the casing is no east task .i got lucky .i used a thin blade to gouge out the glue around the base enough to get a thin blade up around the outer casing .i went slow and kept working that blade in as far as i could .
i eventually got it off .it wasnt perfect by no means but was useable .
i glued it back on with super glue .then ran a bead of silicone around the small gap at the bottom .
in the end it only lasted a few more months then failed again so it really wasnt worth the time .when this one goes i might try the sirio myself .
i dont think theres anything wrong with your antenna that some more tuning wouldnt correct .mine were spiking swr into the red and receive would come n go .
i attest that to to many drive thru`s and tree limb strikes .
good luck .
