We need more information. How much air pressure are you carrying? Is it the top of the tyre that is facing out or is it the front of the tyre? You shouldn't have had to have the lower arms replaced 4 times in 5 years. How many miles/kilometers do you drive in a year? Why are the lower arms replaced so often? This is unusual unless the roads you drive on are extremely rough. I think you should take it somewhere else to get it tracked. I don't think that whoever has been doing it knows what they are doing. I do work on front ends and you should only need it tracked about once every 5 years with normal driving. Also, control arms should last at least 10 years.