Drive train for High Power Engine

[Nothing Special]

....It does shift like a truck, but I have driven trucks for many years and can live with that.

What does "shift like a truck" mean to you? I've driven T18s and NP-435s which I would say shift like a truck and I'd be very satisfied with any of those in a pickup or Bronco (although maybe not if I had built the engine like the OP has).

But I've also driven a 1970's vintage U-Haul truck that had to be double clutched to upshift and could hardly be downshifted at all. That also "shifted like a truck" and I would not want to drive a pickup or Bronco like that.

And then I had the '08 F-250 and the ZF6 shifted worse than the U-Haul truck. Everyone that drove it said that it was terrible. The Ford dealer tried adjusting linkages and the clutch, then put a new trans in it, with no improvement. After it spent 30 days at the dealer I filed a lemon-law claim which resulted in Ford buying it back from me.

So overall I'm not a fan of ZF transmissions, but I don't want to tar all of them with the same brush if it's not warranted. So I really am trying to collect data. How does a ZF5 shift compared to a T-18, NP-435 or 1970s vintage U-Haul truck? My one data point so far is that it's between a T-18 and an old U-Haul truck, but I actually want other opinions.

 

[DirtDonk]

...I would run the '77 style banjo housing...

Just for clarity's sake, the "banjo" style housings are the earlier, pre-'77 style with the rounder shape (like the one in the exploded diagram at the top of this page: http://www.wildhorses4x4.com/category/Bronco_Rear_Housing).
The '77 and later and full-size truck 9" housings are mostly called the HD, or heavy-duty housings (such as the center of our #8689 housing on the same page) are the ones you're recommending. I thought I had heard another name to describe the later style too, but can't remember.

The earlier, weaker style you're recommending against then, would be the "banjo" housing.

Paul

 

[Apogee]

Just for clarity's sake, the "banjo" style housings are the earlier, pre-'77 style with the rounder shape (like the one in the exploded diagram at the top of this page: http://www.wildhorses4x4.com/category/Bronco_Rear_Housing).
The '77 and later and full-size truck 9" housings are mostly called the HD, or heavy-duty housings (such as the center of our #8689 housing on the same page) are the ones you're recommending. I thought I had heard another name to describe the later style too, but can't remember.

The earlier, weaker style you're recommending against then, would be the "banjo" housing.

Paul

Sorry...meant "broad/gusseted" housing and said banjo. I must type faster than I think. I edited my previous post for future clarity.

 

[nvrstuk]

Paul hit on just about everything...

I've broken a fair bit of stuff... a few of these were pre-418 stroker...

Might show you weak points

D20 cases, 4 of them
D20 output, 1 (then went 300M)
D20 low gear set, stripped the teeth off
now KluneV/205

9" stock HD '77
bent 3 housings
grenaded pinion support
went Nodular
twisted 6- 28 spline axles
twisted 1 - 31 spline axles
35 spline ARB case (twisted in half)
now RuffStuff w/TruHi9, 35 spline w/14 bolt hubs

leaf springs-snapped 3 sets
rear spring hangers 3
4 link now


Anti-wrap bar (DOM) 3 point mount very HD
snapped 1 1/2" DOM

There's more but this is a start that you might look at for what you might need.

NEVER bounced on rocks or hammered it in high traction situations. 90% of these were 2wd

 

[Crush]

Mazda m5od trans shifts pretty good. Better than a zf

 

[Nothing Special]

Mazda m5od trans shifts pretty good. Better than a zf

Yes, but can that handle the torque of a 408 stroker?

 

[AZ69EB]

I'm going the same direction as you. My 408W swap is still a work in progress. Well, I guess I need to start working on it again to be in progress. Life happens. With that said; I sold my ZF to go 4R70W. I knew I would not be happy trying to row through the gears with high RPM's having to wait for the next gear to grab. It's a truck transmission plain and simple. Mine shifted a whole lot better than any NP435 that I ever drove. Period. It was also recently rebuilt. But, 2nd to 3rd shift was slow unless you wanted to force it / grind it into gear. It would not be fun playing in the sand or on the street. My progression of transmissions have been stock 3 speed, C4, skipped the NP435 to go with the ZF. Having 4.88 gears would not be fun without overdrive on the freeway. Plus, I put too many road miles on my Bronco to not have an overdrive. Put, the word out and find a few Bronco's to drive with the different combos too make an informed decision. It's your money, spend it wisely. Good luck and have fun with it.

 

[nvrstuk]

I only posted the busted list to show what the weak parts are...

ZF I think you'll hate...wide gear splits and slow shifting

435 is a tough trans but it's a prehistoric tranny. Great on trails, no fun on the street.

I got so tired of the gear splits in every situation with the ZF, I went with a 4r70W...

So much of this is personal preference, AZ69 said it right...try to drive a couple different ones...

Have fun, it's your rig so do what you want!

 

[Broncobowsher]

Read the first post again...

Top loader 4-speed. rarely offroad, doesn't go faster than 55. Don't need the wide ratio of a big truck trans (although if the 435 is already a happy choice that can stay).

Atlas transfer case. Bomb proof. Fits. Isn't ancient cast iron that is going to take away the fun of the stroker. Isn't that much more than the upgrades to a D20 that still isn't as strong.

Driveshaft with bigger U-joints. At least 1330s, and if they fit maybe bigger.

A new 9" axle. Housing, 3rd member, shafts of at least 31 spline and 35 better.

Torque arm of some sort. Not the little old school duff traction bars that bolt to the front spring hanger and U-bolts. But a big beefy arm. If not actually going full link.

For 90% on road, I would sway bar front and rear.

 

[nvrstuk]

True toploader...
I ran a true wide ratio 4 spd toplaoder for years and years . Loved it, adapted a Heep top cover shifter to it since the mud would gunk up my Hurst 4 speed linkage so bad it would barely shift...spray the mud off and you were good to go for another week ( my 1/2 mile long driveway was a farm field for 7 yrs- fun stories).

Anyway 2 AA main shafts later due to poor quality control at AA and I went to a ZF back in '00.

With this trans you could go 4 spd Atlas and still have low gearing for off-road!