What is the strongest gear reduction setup out there for CHEAP!! Here's what I've come up with:

NP 435 mated to NP 205, cost?
NP 435 mated to Dana 20, cost?
NP 435 mated to Dana 300 (for later 4.0:1 reduction from terraflex)
Possible Auto swap to what tranny?

My 74 bronco doesn't have a body lift and I really don't want one so that is also a consideration. What do you guys think? What setups do you have for relatively cheap? Thanks for any ideas

Well, the NP435/205 came from the factory and are easy to find. No adapters would be needed, but you would need to fab a mount, and drivelines would need to be modified. Tranny also has 31 spline output. Not sure if the 205 fits into an EB very easy.

NP435/D20 needs a $400 adapter. Otherwise it's pretty much bolt in. Tranny would have the 28 spline output......You'll likely nuke the case before the output. You can also find cheaper home built adapters.

NP435/D300 would require adapter, flip kit, and driveshaft mods and a new mount. Probably the most costly option.

All in all, I'd probably stick with the D20 since you already have it. It's also geared lower than the 205

You can find the adapters for the Np435 to D20 for $250, thats how much i paid for mine. Ive seen them on Ebay before. I agree though that it would be the cheapest. Then if you wanted to get lower gears later you could add the Dodge 203 box.

Originally posted by Nobody

NP435/D20 needs a $400 adapter. Otherwise it's pretty much bolt in. Tranny would have the 28 spline output......You'll likely nuke the case before the output. You can also find cheaper home built adapters.


What year of vehicles do I need to search to find this NP 435 with the 28 spline output? How much am I gonna have to change my driveshafts? Thanks for the help!

While upfront it may not be the cheapest, you should take a look at WH Crawler gears for the D20 http://www.wildhorses4x4.com/33.asp#tera They are a little pricey $800, but you dont have to mess around with adapters, driveshafts and body lifts. Just my 2 cents

Any 2wd NP435's will be 28 spline, and also the 4wd trannys that came mated to the single speed dana 21(no low range) will be 28 spline. Average price for a used but good NP435 is $75-$150 around here.

If you buy the AA adapter, driveshaft mods will not be necessary

The cheapest and strongest gear reduction will be the 435/205.
How do you plan on building your eb and what do you plan on doing with it.
If your going for moderate trails with little technical rock crawling then do the 435/205. If you go 1 ton definetly go 435/205.
If you are doing technical rock crawling with a moderatly built rig with 38's or less go with 435/20.

The 435/205 leaves a little to be desired for rock crawling if you don't have alot of torque and big tires.
I have the 435/205 currently because I wanted strength with the big tires and 1ton axles. I just recently added a klune and now have a very stout drivetrain with gearing options for all types of terrain. I used to have the 435/20 setup and was very happy with it till I went bigger making the 20 the weak link.
So it mostly depends on how you build your rig and for what terrain.

I have the np435/205 out of a 4wd. Only Mod that was done was the xmember which I made a few extras to sell. Driveshafts was dead on for me. Rear I had to put a smaller slip yoke on and front vice versa. You will have to find the yokes for the np205 to mate to the bronco driveshafts. We found mine from 78-79 big bronco. Which I think was an automatic(I might be wrong on this).

Cost in total was like $400.00(High estimate)
However any np435 will make you pull your hair out trying to get it to fit without a body lift.

You don't neet to pull out your hair, just your sawzall, grinder and air chisel.

Yeah you can cut lots of the tunnel out. Its so tall that it makes it very tight.

I guess if you cut enough out you could just drop it down in place from inside the cab.