530 and 570 jumping out of low range

Both are older tractors is this a common problem and how can it be corrected?

Clearly those steads don't like going slow.....

Pull the cover plate off with the shifter fork attached and take a "look see". My guess is you will find the detent ball or spring (items 17 & 18) might be stuck or missing. Or, the shifter rail set screw (item 15) might have worked loose causing the fork to not travel properly... I'll bet it's fairly obvious when you get the cover plate off...

DADs 430came here new , and we broke a fork somehow rite after we got it.DAD let EVERYONE borrow the 430 ,and the dealer benifitted from POPSs genorosity by selling more CASE to the nieghbors
,we .never broke it again and that 430 has ran 10,000 hours.. however , Every triple range that ever came to our place had a problem somewhere,,they were easy fixes, AND that was why we got each one for a reasonable price .... Mechanix will claim it is caused by rammming and crammin and SLIP SEATING Different drivers and hotrodders,.I AM CERTAIN the odd shift pattern ,for 1st time shifters IS THE CULPRIT .We had to show everyone how to GET LOW RANGE ,or else CRAMMIN would occur,.. Once taught No problem.. I would bet,inexperienced new drivers, and your problem is the reason why Tenneco dropped low range on the 70 series ... Just watched a 6000 hour Loader tractor 511b bring $2800 , it wasnever painted or refurbished other than a clutch. bought NEW in 1957, stayed with same driver ,, triple range worked perfect..it was diffinately in its work clothes ,, but sound for 6000 hours, a friend of my brothers got it.. Another Common problem with ineperienced drivers is the hand clutch ,.. The half moon key will break if it is ramed hard or abused ,,we usually tractor split to fix that ,but not sure if you need to..