friend just bought a 1972 7520 syncro / it has two shift levers that say I and II and Hi Low so in my opinion this gives each gear 4 speeds / example 3rd gear has I and II and High Low / am I correct??
sixbales chose incorrect 7520 on Tractpordata site. The following links are for the correct 7520. Shame on JD engineers for duplicating model #S. I always thought it was unique that the famous model 4020 model # wasn't duplicated by JD engineers.
TractorData.com John Deere 7520 tractor information