If it whines and sounds like a supercharger on acceleration and deceleration, I will bet it is the imput shaft getting ready to let go. Although you may get away with it for a while it will fail. As for parts to do the rebuild correctly, new imput shaft, contershaft, 2nd and 3rd gears, and the rebuild kit will run $550. I could rebuild it but the shipping would probably kill you from TX to PA. I would call D&D or Hanlon for the parts, either should have them in stock. The aftermarket shifter will increase the road noice heard through the shifter because it is a soild nice piece not the flimsy poor excuse for a shifter that the stock one is. If it were the syncros it should grind or pop in or out of gear or sometimes not want to go into gear, 2nd gear has trangle shaped ares to allow the gears to slide in, it is famous for getting flat when power shifting. The reaseon you only here it in 1st-3rd is 4th gear is a direct drive and has a lot of load on the tranny so it is there but is harder to hear it.
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