Which side of the vehicle is the steering wheel on? I am assuming you are not in the USA, so it is on the right side of the vehicle? If this is the case then they are not adjusting the alignment to your concern. They are just putting them in the center and letting it go. This is very typical of people performing alignments. If the complaint is a slight right drift then you need to set the numbers to counter act that and cause it to go slightly left which will cause your vehicle to go straight down the road. I would always do this by increasing the caster split so that the side I wanted the vehicle to go towards (left in this case) has the least positive caster. That means the caster needs to be lower on the left side. Caster doesn't effect tire wear or any other performance unless you are taking it out of the specified range. Yours is actually high on both sides so its okay to come down a little.
I would suggest setting the caster split to between.5 and.75 (lower on the left) to start and see how the vehicle drives. This means the 5.30 that I circled needs to come down to around 4.90. Clearly if they just set this side at 4.90 and the right side comes down slightly as well then it won't have the same effect that is why you adjust based on the split or difference between the two sides.
If all this is accurate, I bet the vehicle will actually go left a bit which means they come back and cut the split in half and it should go straight down the road. Meaning if after they drop the left side so that they are a half degree off from each other and it goes left now, they need to bring the left side back up so that the split is now.25 side to side.
Does this make sense?
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Sunday, January 5th, 2020 AT 5:44 PM