A year ago I started to experience slow deflation of the tyres on my then 4 year old Freelander which has 18” alloys. My local tyre dealer (ATS Euromaster) found a slow puncture in one tyre but they said that the leakage in the others was caused by inner rim corrosion caused by the clip on balance weights. They changed the weights on all 4 wheels to stick-ons. Since then the leakage has continued so, despite wear on the 35,500 miles tyres being still within legal limits, I bought 4 new tyres to eliminate one possible cause. Within a week one had completely deflated and another was had lost 5psi. On returning to the tyre fitters they applied black sticky rim seal to the 2 tyres. By the following day the worst tyre had lost 5 psi. I suggested that the inner surface of the wheel should have been cleaned with a wire brush or some such before the new tyres were fitted if this was such a common problem. This he did to the worst tyre before applying fresh rim seal. The problem has eased but still not entirely gone away. Is this a common problem with alloys? What is the solution once this condition has been experienced?