I think you have answered your own question if the Repco coolant is damaging your car and you put 3 litres in your dads Laser and his radiator is blocked and has to be replaced that would tell me to through the Repco crap away. I use Nulon OATS pre mix never had a days trouble with it Repco say there coolant is made by a quality manufacturer but can't or won't say who this alone would make me suspicious of there product hope you fix this problem soon.
Phil

