Cant get SWR below 3

I always had better luck with Francis antennas. for store bought stuff.
If you aren't afraid to spend some money on a very good antenna go to Tulos electronics out of Star MS. I bought mine back in the early 90's.Troy Tulos will set every thing up and I guarantee you will have an above average set up. He builds antennas for nearly every kind of set up. from the ground up.
99% of high SWR problems is bad grounding.
Run a braided ground strap from antenna mount to door ground then to cab then to chassis. Each one as short as possible. It could be your mic is going bad. If your radio is hearing but not talking.
If the coax is running though the door jamb you may be pinching the foam in side the coax and allowing current to flow down the out side of the coax. You may not see a distinct pinch with door open.
I do not run truck stop coax as it is for the most part junk. Use some RG 58U . Same as hams run .
It is not the radio that gets out but your antenna that does it. Coax is part of the antenna system. Assuming you run one antenna and your radio is 4 watts out your getting 4 out the antenna. Co phase is two antennas and each one is sending out 2 watts.
http://www.stargun.cc/
601-845-7099

 

SWR that high means there is no ground plane for the antenna...

 

You seem to have an antenna ground plane problem since your SWR reading is 3.0 or higher. Do a search on antenna ground plane. This has been covered to death in previous topics. There are a number of topics that should give you an idea of what you should do to correct things.
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I would not change antenna or coax until you fix the antenna ground plane. Once your antenna ground plane problem is solved, you maybe satisfied with what you alreadly have. If not satisfied, I would recommend that you have the radio checked by a competent cb tech to see if you power transistors [what some call the "finals"] have been damaged. I hope that is not needed; but, using a radio with an excessively high SWR reading can affect the power transistors that are in the radio.
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.Personally, I would crack the driver's window and run a short length of coax from the antenna mount through the window and up to the radio. But then I would keep the driver's door closed and go in and out of the passenger door.
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.When you are running just one antenna, you require 50 ohm coax. Either RG-58 or RG 8 coax; your choice. There is really no need to use really expensive coax unless you are running a high power setup. For a stock radio either one will work for you.

 

I would say bad ground. A lot of the new trucks have plastic mirrors, not good for grounding. I know some guys who run a ground from the antenna to the frame of the truck. Not the easiest thing to do, but well worth it. Maybe a CB shop could do it for you.

 

If you have some old RG 8 laying around just strip the outer cover off. Use the shield braid . Cut off several lengths. Put a lug on each end. put ground from antenna to door bolt. door to chassis and chassis (cab)to frame. The shorter the better. Fairly easy to do. I had the same issue with my Lil Tarheel II on a Freightliner . That is how i corrected it. Now very good SWR.

 

best advice......imo!

 

Sounds like coax issues.

 

Truck manufacturers use really bad coax that is designed for receiving and not transmitting. I had to re do the coax in every truck I drove. it is the same coax that the AM FM radio uses. at least that is how it used to be. Manufacturers may have had an awakening since then. No matter what they use today it still is not very good. .

 

with the coax disconnected from the base of the antenna check for continuity from the antenna mount to the frame of the vehicle, no continuity not gonna work