NP435 Trans Swap Help
Only issue, NP435 trans is a little noisy in 2nd, a lot in 3rd, and quiet as can be in the rest.
It still drives along, does 80mph at 3k, just not a fan.
I used to rebuild manual transmissions for a living.
I have rebuilt probably hundreds of those 435s and even more transfer cases.
If yours is;
not jumping out of gear,
not grinding going into gear, and
not too slow to shift; then
all it needs are bearings, which are cheap and easy to change.
Altho, if it was mine, I'd convert to 2-wheel drive and
in goes the Mopar Loc-up overdrive. BUT, in all likelihood, if I did that,
the starter gear might need to be fine-tuned.
Nice looking truck.
EDIT
As far as manual transmissions go, this one is pretty simple. It would be really hard to muck it up. but they are heavy. I used to build 2>3 a day, start to finish, including those funky "inside-out" synchronizers, and repointing the clutch teeth.
But you're right, those transmissions had several different "farm-truck" type ratios. Some with a quick 1-2, some with a quick 3-4.
On the street, with regular height 29/30 tires , that granny-gear was near useless, making the trans more or less a 3-speed.
But I gotta say, coming up off the field with a 12/14 foot box loaded right up; granny gear was sometimes all some of those gass-farm-trucks, could pull, back in the 70s/80s.
However, those short 4th boxes might be nice for a 318 ..........
But I agree, if that granny-gear is useless, then it might be just as well to get rid of it. However, for you, the bigger issue, I feel, is that 3000@80 mph. Which points to the rear gear actually being a lil much....................... which would make it prime for a Mopar .69 overdrive which would bring it down
to 2100ish@ 80. That's a win/win; triple-win if the unit has a lock-up..