Get a "train " air horn kit. Mount the horns under the truck, use the regular horn wires/connection to activate them with the factory horn button!. ALWAYS Remember the 3 Second driving distance rule, and look way down the road as you drive to see what others are doing. It is called the "Smith System of Driving". Figure out whether you want to change the sound ( you never use it in anger - you just use it to admire its sound) or YOU are a problem, I won't say "THE" problem, because as it has been said here that the readers of your question do not know "how often you NEED to use it, or how often YOU do use IT!!!! Is that a better way to say it????? I would venture to say that if someone walked down the road about an 1/8 mile away, and your horn was "engaged" they would probably be able to here it. What I did on my vehicles, to get a more distinctive sound (that made me smile) was to add an old school burglar alarm horn in series to the O.E. horn. Amazon has an Avital brand part no. 514L (ASIN no. B077VFXQu6for $10.95 (Horn with wires) For those that want a gentle horn, on our Motorcycles I replaced the stock one with a universal one from NAPA part no. 7301043.
PS; two short beeps is much more "friendly" sounding than a push the horn button thru the steering column blast. Improved driving skills can always help. No one is to old to learn.