I dont no why people worry about a tracker in your van if you are doing your job properly there isnt a problem it only effects people that like say there there when there somere else or they have started late or go home an hour early and at the end of the day if you need of early or have an appointment for something if you tell your manger 99%times he will let u.
Most companys like the tracker because they can prove the van was on customer sites for a certain amount of time if there is a problem in the billing.
Further more when managers look at the times of the tracker there not interested in the guy that had an extra 5 mins lunch or a guy that has slept in buy 15 mins the there looking for constant pattern like the guy always sleeps in or is always knocking of early or the guy is constantly doing private errands during work ours.
But one thing i would say in the defence of mobile engineers if its so important to track engineers what about the managers shouldnt they be tracked as well to see what they are doing after all most managers in this game are mobile as well and how productive are they in visiting there customers and mobile engineers and are they abusing there company fuel cards at night or weekends and thats why a fair system would be to track everyone that has a company vehicle and that way everyone is in the same boat.