I bought this truck about a month ago, but before i get it inspected i need to sort out or swap the transmission. 1st gear seems to grind and jump when i try to shift, second is fine, 3rd is fine, 4th gear most likely works but i can never get it into gear. The guy i bought the truck from told me the fork is probably bent but after opening it up i cant find any bend or problem with the shfter. Reverse works but very noisy and geary sounding lol. This is my first standard truck but judging from the other gears it doesnt sound right. I have heard that the plastic tabs that go on the ends of the forks have to be there for the gears to shift and i know that one of them fell off. I also have a np435 transmission in a 1978 f150 that i could probably swap in if the gearing is the same. Anybody ran into this before?

 

1st is non-synchro in this box, so is that your first gear trouble? You can't downshift while moving, and 1st to 2nd needs to be 'slow'.

2nd to 3rd, not problems--but won't go into 4th. You see nothing wrong when opening up--as in a tear down? Check all the specs, etc.

Clutch is ok, right, as it shifts ok 2-3 & 3-2???

From what I've seen, there is only one version of the np435, so ratios should work from your other truck.

Good luck.

 

Thanks for the info about the gear ratios, thats what i was wondering, as for shifting, i have to start the truck in second because 1st gear seems to grind. shifting from 2 to 3 and 3 to 2 works fine and 4th gear feels like it shifts into the right general area but wont engage at all.