Yeah them 37s will definitly make it go faster than stock. Im not sure what trans is in the 85 I need to go under there and get the tag off it and see. It looks identical to the np 435 in my 76 though. I dont know if that came in these trucks or not. My 76 also creeps in first with about the same top speed as my 85 does. I didnt see the 435 on there so I dont know what kind of ratios it has.

 

A 1985 probably has either a T18 or T19 in it,and the T19 is synchro'd in 1st gear

 

It has a cast iron case and the pto port on the passenger side. I also cant speed shift it like the 76 so its probly different. The thing is really startin to rattle alot and all the gears are loose so when it goes I think im gonna put a 435 in it. What do yall think?

 

Are you gonna need an adapter from the Borg-warner transfer case to the tranny? im not sure whether one is made to adapt an NP435 to a BW married case? Both the T18 and T19 are well regarded,heavy duty tranny's,of comparable strength to the Np435.

 

I dont know it was just a thought when this one goes out. Alot of times it is hard to get it to come out of 2nd gear and 3rd makes noise in the case like its slippin and 4th is the same way. The fluid is up and fresh, the clutch is a couple years old and dont slip. Maybe ive been towin too much weight with it for bein a half ton? Ya think towin a tandem axle trailer wth a 77 1/2 ton on there is too much?

 

yea probably.....
Whats the towing weight of the trailer/truck?

 

Dont know but it squatted that poor old 85 down alot. It pulled 65 just fine but we had a cross wind so it was startin to heat up. We have also had my jeep on a different trailer that was built for a loggin company in Idaho that trailer musta wieghed a good 2 or 3 thousand pounds by its self it was 16 feet long and had rugh cut timbers for the deck and the frame was from one of them mobile construction offices just shortened down. It had dayton wheels on it with load range F tires. The tounge alone was made of 12 inch C channel. My dad put two palets of stone on that trailer and it didnt even squat the springs on it. We put that one behind my moms 99 350 with a v10. We shouldnt have sold that trailer but we didnt need it anymore.