You...
EU and Swiss citizens can get a visa upon arrival to any road, port or airport border crossing. Price: 10 JOD. No vaccination proofs required. Theoretically you need an International Drivers Licence if you're a Westerner, practically they are only interested in your vehicle documents.
... and your vehicle
Car, diesel fuel, 30-day insurance 21 JOD. (March 2005)
Truck, 7-day insurance 20 EUR, diesel tax 100 EUR (the vehicle left thecountry within 7 days, no info on the diesel tax validity). (August 2007, source: Brane Krajnc - Barbara Prislan)
Diesel 0,315 JOD, unleaded petrol 95 0,430 JOD. (November 2007)