Ford's have had a problem (there is a TSB for some models) with electrical noise from the fuel pump.
It can come in two different ways. From the power/ground wiring, or via the antenna.
Your Alinco, I presume, is an FM rig -- you will have not problems with FM typically because the modulation system itself is inherently noise immune. Also, the intensity of radiated noise from most arc type noises drops steadily with frequency and if your Alinco is a 2 meter rig, it's at 5 times or so the frequency of the CB.
So, we're back to seeing where it comes from. For starters, do you ever listen to AM radio? Put you factory radio to use and tune in a weak AM station and see what you get.
Ground loops are a killer. Sometimes not grounding the antenna at the base of it increases noise sensitivity since the effective signal reference path from the base of the antenna is through the vehicle body which carries all the return currents from the electrical systems. This can be disastrous. If your antenna feed line is not grounded at the base of the antenna, do that and see if it helps. By having the ground reference return through the coax shield, you may reduce noise.
Now here's the funny part: sometimes grounding the feedline at the base of the antenna INCREASES noise (though not usually). The occurs only when there is such a crappy ground path back to the battery from the fuel pump, say, that the fuel pump uses the coax shield as a ground path for it's motor current to some extent! The solution here is to rework and restore any damaged or missing ground straps. There are a couple under the truck between the frame and the body and you should inspect them.
Just some things off the top of my head to think about.
I always run a separate ground right from the battery to any critical radios, or radios with noise problems.