Ok I have a 74 bronco that had an auto, I want to swap for a stick for several reasons but can't decide which one

A nv4500 seemed like the answer, but I'm not sure now. the truck gets used for mostly sand dunes and some street cruising right now but I'd like to try some rocks and run more trails then I do now. My problem at the dunes now is not enough power to run high range and the dana 20's low of 2.46 is to low. My original plan was a nv4500, keep the dana 20 and regear the axles from the current 4.10's to something like a 5.14. The cost of the nv4500 and the adaptors got me thinking about just putting in a np435, it would be a lot cheaper but wouldn't really help at the dunes unless I geared down the axles and without overdrive the limited amount of street time would really suck. So how about a np435 and a stak 3 speed monster box? I'm thinking that I could go with a 2.1 and 3.1 low, or something close, and get the use of low in the dunes, a use able road speed, and a decent crawl ratio.

So am I nuts or heading down the right path?

I'm also open to other trans choices, except autos, I'm sick of dealing with c-4 issues and won't go that way in this truck again.


Brewchief:D

i've got an NV4500/205 behind my 460 and i love it. with 37's and 4:10's it would be nice to have a little lower final crawl ratio but it does pretty good for what i do.
whats really nice is putting down the highway at 65mph turning 1600 rpm's.
i was lucky though and scored a good deal for the trans and adapters all together.

fuck nv4500's..

put in a ZF, lighter, cheaper, easier to find, and goes in with no adapters..
plus imho, its a better tranny

autos are the devil. :evil:

that is all.

fuck nv4500's..

put in a ZF, lighter, cheaper, easier to find, and goes in with no adapters..
plus imho, its a better tranny


cheaper and easier to find my ass.:flipoff2:
yeah stick with the ford stuff if you can but good luck.

Unless you're towing I don't see much of a point to the ZF. A NP435 with 3.08's has the same ratio spread as a ZF with 4.11's.

So say with some more practical numbers you went from a 435 with 4.11's to a ZF. You'd have to run 5.13's with the ZF to maintain your crawl ratio and even then you would only get a 5% reduction in cruise RPM.

The 6.32:1 4500 has a spread closer to the 435, so if in the example above you went to a NV4500 you'd only have to run 4.56's to get your crawl ratio back and then you'd have a cruise RPM equivalent to having a 1:1 with 3.32's, which is a 24% reduction.

So take from it what you will.

Justin

No towing, LOL an early, squirrely bronco is not my idea of a tow rig in any way shape or form. My biggest problem is lack of speed at the dunes, I don't have the power to run high range all the time and if I run in low range I find the rev limiter all to often, I think a 2 to 1 t case ratio would be just enough to bring the revs down. The reason I was thinking about an overdrive trans was not to bring cruise rpm down but rather allow deeper axle gears, this way I could run high range on the sand. My current cruise rpm is fine, I had a c-4 with a very lose converter so even at 1-1 it will probably be better than it was.

Brewchief:D

Ok after running lots of numbers I keep coming back to the np435, stak 3 speed w 2.05 and 3.75 low ranges and keeping the axles at 4.10. This will give me the higher speed I want at the dunes, my cruise rpm will stay the same, and I will have a crawl ratio just over 100 to one. The cost looks to be close to what it would be to do a nv4500 with the dana 20. The only problems I'm worried about is the ability to shift the np435 fast when needed, this will mostly only be a problem at the dunes, any ideas? Any reasons not to go this route?

Brewchief:D

im sorry I didnt read any of this thread on account that your avatar is way to distracting.:flipoff2:

Np435...no questions asked.

Search for "short throw" shifter or some other key words might find it for you. I have read several threads on homemade "quick shifters" right here on the ford board. Some one even makes them and sells them. In the short wb bronco I say np 435 it! Your driveshaft angle will thank you.

autos are the devil. :evil:

that is all.

X2

im sorry I didnt read any of this thread on account that your avatar is way to distracting.:flipoff2:

and again! X2 :D

NP435 sounds like the way to go....lower axle gears in dunes with a v8 will prolly end with a boom of poof one day while gettin throttle happy. Plus your rear driveshaft is already way short.

im sorry I didnt read any of this thread on account that your avatar is way to distracting.


I didn't want to be the first to say anything.......But.... FAWK!!!!!!!!!!!!!! :eek::eek::eek::eek: Nice balloons!

Somebody did a 2wd ZF swap where he used the stock D20. Nice writeup of it on the interenet somewhere. not on pirate I don't think.

Is it possible to swap in some scout t-case gears to get to 2:1?

I can't imagine nv4500's being more plentiful than ZF's. I found my 460's 4x4ZF in a JY for 150 bucks. I had to pull it though.

Small block ZF's are a lot harder to find than the big block versions. If you do go the 435 route you might want to look at this shifter :smokin: http://www.wildhorses4x4.com/product/Gear_Banger/3-Speed_Transmission

I think you can use the scout or jeep gears but I'm not sure, I looked at doing that with the auto but that's as far as I went. My needs are changing and I would like to have the ability to use this as a sand truck and try my hand at going slow over big rocks, that's why I'm thinking of going with the stak 3 speed.

Lower gears in the axles would be fine in the dunes because I could stay in high range, I don't think the motor would like to cruise to work anymore though.:D

The wheelbase may grow soon so drive shaft length shouldn't cause to many problems.

That shifter looks like the way to go, the one you linked is the bling version, they show a raw steel one to that's cheaper.

Thanks for the comment on my avatar, not bad for a girl in her mid thirties:D

Brewchief:D

I have a 5-speed out of my 96 with 1356 transfer case. It worked great at the dunes.