transmission

[walkercreekbronco]

While my old 302 still runs decent, it leaks a quart of oil every 4 hours while running. The old engine isn't worth spending the time or money to seal it up. I have a spare block I'm thinking of having built into a 347 for low end torque.

How long would a 3 speed hold up to this kind of power? What about the NV3550? The NV3550 seems like the ultimate transmission upgrade, but will it hold up under abuse?

I have 33 inch tires, 4.11 gears, Detroit Locker in the rear.

 

[Catchin1]

WCB I've read been reading all post on this site regarding that question. I have no personal experience but from all I've read the NP434 is the toughest. I also have 3spd and have been considering a swap. After reading it all I'm second thinking it. All I intend to do is ride around and maybe muddbogg a little around the edge of some fields while I'm out hunting. The 3spd has always held up good so far. Would like to loose the dorky column shift tho. I know my son coming up is gonna feel the same. Think I posted earlier, but would like more input on the 3sp floor shift.

P.S. not trying to derail this thread WCB, but we are intrested in the same thing.

 

[S_bolt19]

The 3 speed will hold up for a while, though it is not in any way shape or form the trans the either the NP or the NV is. I don't know too much about the NV, so my knowledge is only heresay. As to the NP, it is a proven work horse and is absolutely bullet proof. In my first EB, I had an extremely well built 289 (that should have been in a Mustang) that was pushing upwards to 425 hp. Very fast, not much on the low end torque though, but anyway, I shelled the 3 speed & D30 within a month of lead footing it around. Just too much gear jamming...I had a hurst floor speed shift kit in it. My current EB has a fuel injected 5.0 mated up to the NP, which has about 250-275 hp, but more torque. I have had this combo for about 5 years now and have never had any problems what so ever. As a matter of fact, I have only come across 1 person who has ever done any damage to an NP. And that was because they had a fuel injected 460, the NP, D20 x-fer, cold duck dual case & 5.88 gears in the axles. That person snapped the out put shaft on the NP in 4-low on a 10 rated trail. It was a combination of a TON of torque vs. the amount of power that caused the problem. Something had to break and that just seemed to be the weakest point. After it was taken apart, the root of the problem was that the output shaft had a hairline fracture in it to begin with and....POP....there it went. The NV (and take this with a grain of salt, because like I said, I am not real familiar with them) isn't as strong as a trans as the NP is, but it is stronger than the 3-speed by far...for what ever that is worth...just heresay.

So, needless to say, My personal opinion, if you plan on doing mudbogging, or just minor off roading, stay with the 3 speed. You can generate higher speeds with a fairly close gear ratio. Go with the NV if you do a lot of highway, some mud bogging & some rock crawling. Go with the NP if you don't do much highway, plan on doing rock crawling and want the lowest gears in the business.

 

[walkercreekbronco]

s bolt, you said the 3 speed will run higher speeds than the np. Don't they both have a 1:1 ratio in top gear?

 

[S_bolt19]

Ya know, I don't honestly know. But I do know that before I put the NP in mine (before 4.11 gears) I could run at 80-85 mph all day long and when I put the NP in I coudn't without running at much higher RPMs. Soooooo....I dunno :huh: