now then,does anybody know what year sierra my rear drum brakes are off??i've just brought a set of the bay advertised as 1984-on,but they are only 38mm wide,my old ones are 54mm wide with code 943535 ,can someone help regards wayne

Have you measured the diameter of old and new?? Some models had the 8inch drums which i would guess are the 38mm wide ones, as the 9inch drums used on 2L cars are wider.