help please. My 90 250 5 speed shifts up 1 through 5 perfect and flawlessly, however on the downshift it grinds going into 4th and then into 3rd. if i slow down and slowly ease into these gears sometimes they shift fine. would this be the synchros? it only does it on the downshift side. upshifts fine. I just replaced the fluid with 5 quarts 5w-30 synthetic. thanks much.

 

have you tryed to doubble clutch it ?
and a perfict down shift is hard to master from the years i drove semi i dont use the clutch for an up shift or a down shift just the right amount of throtle but it sounds like the trany is fine

 

could your clutch not be engaging 100%? just enough to where when its all the way in gear it snags just the slightest bit?

or possibly your trying to downshift into a lower gear too soon before the tranny wants to

 

Well dont know for sure but i dont think its the clutch because it does the same thing when i dont use the clutch at all on the up shift or down shift. shifts up perfect and grinds third and fourth on downshift with or with out clutch.

 

sounds like your shifting too soon every thing seams fine

 

A friend of mine had the same problem and it ended up being the synchros.