Having tried a few, we have come to like this one best:
Shark Retractor Vac Model: EP187
We bought it at Walgreens. It is available online too. After using it, I liked it so much that I bought a second one to keep at home, just in case they discontinue the model and our current one gives up the ghost.
It uses no bags or replaceable filters, but its powerful motor pulls up fine dust better than any vacuum I have seen. The filters capture the dust instead of sending it back out into the air, only to settle in the truck again.
It is amazing how much dust this little guy can suck out of the sleeper carpet, floor mats, throw rugs, cab seats, and dinnette cushions. After each use, I just open the vacuum cleaner case, remove the filters, and tap them on the concrete to get the dust out.
With dog hair to deal with, I would expect the filters to fill up more quickly. If they get too packed, the vacuum cleaner will overheat and shut itself off. It can be restarted again after it cools and the filters are cleared. The clogged filters and overheating can be an irritant, but I prefer that to a vacuum cleaner that leaves the dirt behind.
The carrying case and retractable cord make it easy to store this compact vacuum cleaner and attachments when not in use.
At $39.99, the Shark Retractor Vac Model: EP187 is a bargain at twice the price. Buy now while supplies last! And may the joys of truck vacuuming be yours.