I got bit by the 1356!

Ron asked what I meant by "Blue & Gold"

Well, there you go.   😲  😈

Hey Jim,

While you're on the topic of Bricknose transfer cases, I have a question...or questions...

So the Bullnose 1/2 ton trucks used the NP208 T-case? And then in 1987 switched to the BW1356? On the 1987-1991 trucks, the speedo cable went into the transfer case, correct? What T-case was used from 1992-1996? Can a speedo cable be connected to them or do you specifically need an earlier T-case?

At some point they switched from having a slip yoke in the T-case to a fixed you with a splined driveshaft?

Cory,
To the best of my knowledge it is only the tailshaft and housing that has provision for a speedometer cable.
My '87 has a VSS tone ring and sensor but it's only used for the RABS.
Whether the later 1356 has a spot for the gear locating ball is beyond me.
But, if it does, then all you would need is a housing with the boss for a cable.



From what I see in Gary's charts the 1345 was popular too.

The fixed yoke and flanged models were used in Broncos and 150's.
AFAIK all the 250-350 applications had the slip yoke like I do.
350's got a 1356 with an aluminum front case half that has a PTO.
The Zf-5 and T-19 have PTO's both sides.
So there's three options on 350 trucks.

ArdWrknTrk wrote

Cory,
To the best of my knowledge it is only the tailshaft and housing that has provision for a speedometer cable.
My '87 has a VSS tone ring and sensor but it's only used for the RABS.

What drives the speedometer in your '87?

The brick nose trucks have a conventional mechanical speedometer.

PSOM's came later (with the Aeronose trucks, I believe)

ArdWrknTrk wrote

The brick nose trucks have a conventional mechanical speedometer.

OK, I thought so. Where is it driven from?

Cory, my 92 Bronco has an electric speedometer, and I think it uses the rear diff sensor that Jim mentioned for speed and RABS.

Right here on the tailshaft housing, like I said...

ArdWrknTrk wrote

Right here on the tailshaft housing, like I said...

Ahh, OK...I thought that the speedo cable went to the transfer case in the Bricknose trucks. My bad. Now I see what they did. So you have a ZF-5 then, correct? Do you know if they did the same with the M5OD-R2 as well?

The tailshaft of the transfer case.

My truck came with a T-19, I swapped the Zf in.
But the prior 1356 had this same location.

I imagine all '80-'90 trucks do.
Where else would you put it on a 4x4?

ArdWrknTrk wrote

The tailshaft of the transfer case.

lol, OK...never mind. I knew the cable went to the transfer case. When you said it went to the tail shaft, I thought you were talking about the transmission tail shaft. Sorry. I'm a 2wd guy, remember?>..lol.

ArdWrknTrk wrote

....  AFAIK all the 250-350 applications had the slip yoke like I do....

It's been a while since I've been under my truck and I've never taken the rear driveshaft out, but I'm 99% sure that my crew cab has a fixed yoke with a slip joint in the rear part of the 2-piece driveshaft.  I don't know if SuperCabs had a 2-piece driveshaft or not, but I'd expect any truck with a 2-piece driveshaft to have a fixed yoke.

Edit to add:  (not putting this in a new post to avoid too much thread pollution, but editing to make this more complete if anyone finds it)

I was mostly right above.  As Jim says below, it's a flat flange rather than a yoke on the transfer case.  But it's not a slip there.

The other correction from what I said above is that the slip joint is actually in the front half of the driveshaft, but behind the center bearing.

And yes to what Jim said below.  Longer trucks need longer driveshafts, and longer driveshafts don't work so well.  So they get split into 2 sections (or 3, or 4 or... depending on the length of the truck).  The front section is supported at the front by the U-joint at the (fixed) rear of the transfer case (or trans) and at the rear end by a center bearing.  The rear section is supported by the U-joint at the rear of the first section and the U-joint on the diff.  There needs to be a slip joint somewhere between the center bearing and the diff.  In my crew cab that's in the back part of the front section.

I'm sure that a truck with 2- piece driveshaft would have either a fixed yoke or the flat flange.
Maybe extra.long trucks need that companion joint?

Gary Lewis wrote

I remember the bearings to be a real pain on the 1345.

It put up a good fight, but in the end I managed to yank it out (in pieces)





Thanks for your documentation Gary!
Exploded diagrams help a LOT.

I'm having a bit of a time now, because I don't have a vise, any large sockets, or seal drivers.

But at least the *parts coming out* part is over and clean parts can start going in!  👍

Congrat's!  Glad you got them out.  And, glad the documentation is working for you.  

3/16" rod, you say???

Jim, Darth has a two piece driveshaft and uses a normal slip yoke at the transmission then the rear drive shaft has a slip joint just behind the center bearing.

Well, the more you know!
I love the fact that every day's an education.

I can understand that a crew cab long bed dually would need a center bearing but I'm surprised that it would use a slip yoke and an extending shaft.

So what is the rhyme or reason behind which gets what kind of output?

What I found interesting was that my F150 with a 300 and a C6 had a one piece driveshaft, however my 86 F250 donor with a 302 and an AOD had a two piece driveshaft. Both were regular cab longbed trucks. Didn't think a regular cab needed a two piece but apparently the 4x2 3/4 tons and up did.