Hi on the tyers avon it should tell you the year thay where made the 4 digit encircled number ends in 79 were thes made in 1979 my van is 1997 all three tyers end in 79 the tyers look ok no sign of cracks the tird tyer is spare
sorry for all posts my pc just gone hyper!!a four digit number would be the year and week of the year eg..4209 42nd week of 2009