so ive been running a mag mount diamond on the roof of my F150 for about two years now, works fine i guess but the cable routing is a mess and i keep catching it on the garage door opening every few months which is just annoying. been thinking about drilling and doing a proper NMO mount but honestly im a little gun shy about putting a hole in the roof of a relatively new truck.

the mag mount is a D130J so its not exactly a cheap antenna, but ive noticed on some repeaters that are a bit further out i really have to work for the contact especially when im on the highway and the angle changes. wondering if thats just the antenna being mediocre or the mag mount contact being inconsistent or what. ground plane on these things is supposed to be pretty good on a steel roof but who knows.

anyone done the NMO conversion and actually notice a real difference on VHF/UHF? and where did you mount it — center of roof, edge, fender? i keep going back and forth on this

drilled my 2019 Tacoma about a year ago, put a Larsen NMO mount right in the center of the roof. yeah its a hole in a new truck but honestly once you seal it properly with the right mount hardware and a bit of self-amalgamating tape on the inside its just not something you think about again. the cable runs through the headliner really cleanly and i used one of those thin coax runs that tucks right under the door seal.

difference from the mag mount was noticeable to me, not like night and day but the signal is more consistent especially when moving. the main thing i noticed is i stopped getting that intermittent dropout i'd get on the mag mount when hitting bumps on rough roads — that was almost certainly the ground contact moving around. for a daily driver that does a lot of repeater work i think its worth it, just do it right with a quality mount not a cheapo one

the D130 is a pretty decent antenna tbh, probably not the problem. mag mounts on steel roofs actually work pretty well from what ive seen, the ground plane is fine. id check your coax connection and make sure the mount contact points are clean before blaming the antenna or the mount style.

that said i did a hood mount on mine which sounds weird but its actually not bad for a pickup, runs the cable way shorter and you dont have to deal with routing through the headliner. center of roof is still probably ideal on UHF but for most 2m repeater stuff the difference is pretty marginal unless youre really pushing the edge of coverage