AG-CAT pilot reported a vehicle was stuck on the runway while on final approach. Due to fuel concerns; the pilot decided to land overflying the truck by 20 feet.

Narrative

While returning from a Part 137 mission Northbound; the Tower issued a frequency change to local advisories. At 3 miles south of ZZZ; the airfield; I announced my landing intentions. When I turned short final I noticed a white truck parked perpendicular to runway and blocking a portion of the grass runway. The truck was parked near the white displaced threshold markings. I announced on UNICOM: 'Why is there a truck on my Runway' with no response. I then announced; 'get that truck out of the way' again with no response. I was un-aware that three men were out of the truck and were retrieving 'counting' equipment. The equipment was chained to a runway light. Without knowing rather the truck was 'stuck' or otherwise immobile combine with the minimum required fuel I had onboard; I elected to land; missing the truck by nearly 20 ft. In my profession; 20 ft. is plenty of room. I spend the majority of my flight time near obstacles. However; this could of been an absolutely terrible position for an average pilot to be faced with. I intend to discuss this incursion and how we can prevent this type of situation. Note: Time-in-Type was estimated.