My uncle used to drive full time and now is only part time and he told to only haul dry freight, cuz there are lot less issues than other things. Do you agree? What are the issues with the other things and could someone explain placards or whatever they are?

your uncle may be suffering from burnout and is tired. this is probably why he only drives part time now...........

there are issues with dry freight as well.............

when your uncle fully retires, he will be telling you not to drive a truck at all.......which is my advice now..........

With dry freight there really is nothing it. You back up to a dock (typically), unload, drive somewhere else, reload and go. Of course that's over simplifying but that's essentially it.

As far as "issues with other things" you are asking a big question. Could you narrow that down a bit?

Placards are the colorful little signs on the sides of trucks that say "Flammable" or whatever. These are for hazardous materials shipments.

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Z-Lady's devoted hubby.

Sand is dry frt. Its no problem unless it gets wet enroute and gets heavier thus causing one to get an overwt ticket, thus an inspection, thus a lookie at your logs costing you $2000.00 total, Wait dry freight is a problem then. Never mind. I mustve been thinking again. Dry frt is easier than reefer, grain is more fun and long distance dumps are fun too. Even hauled beer bottles all smashed up, smelled good!

Everything has issues. I hauled many dump loads of beer bottles "all smashed up", as you say. I also hauled crushed bottles in gaylord boxes. Either way, the refractory will inspect the load for contamination with bottle caps, rings, plastic, wood, stones, etc. I have had loads rejected. Another problem is the flat tires you get from bottle ends and from whole bottles that roll under your tires if you do not pull forward fast enough while dumping. If your dumper is covered with a net rather than a tarp, freezing rain will turn a load of crushed glass into a block of ice. Then, you can chop it out with your shovel. Crushed glass can also be contaminated by glass of another color.

A more interesting delivery was the load of "flint" or clear glass to Hoosier Art Glass. The place was a converted gas station where glass blower artists made art objects such as the paper weights that contain a snow storm, and paper weights with a rose inside.