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Discussion Starter · #1 · (Edited)
So I have a 1991 e350 short bus conversion with the 7.3 and an e40D on my way to work today I lost power in all gears, checked all the obvious things like connectors for water, atf level, linkage integrity. Crunchy noises from the transmission. No bueno.
Rather than replace the e40d I have been doing some looking around and it seems my 91 year model is in a lucky spot for cross compatibility with the zf5 in some late 80's f350's. I've gotten some confirmation that the transmission bolts up, the pedal assembly can be found as a stock item the master cylinder has a place to go and little modification to the doghouse and perhaps some mounting locations is required but otherwise a pretty painless swap. I havent been able to find anything on driveshafts tho, my bus is 2wd and obviously doesn't have a transfer case like the truck does. Were there 2wd models available with the zf5 in those years? Will that driveshaft work for my swap? Hoping to clear some of these things up. I completely depend on this machine and I need to get it moving again immediately. I'm gonna go junk crawling tomorrow all over the bay area to start putting some eyes on these parts. Any pointers would be heavily appreciated.
http://imgur.com/wZYfaoy
 

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Discussion Starter · #2 ·
Well, I bought the zf and brought it home, I have a mechanic that is doing the tranny swap for me for around 800 bucks while I run around for parts. Since monday when the e40d crapped out heres where I stand.

The e40 is out and my single mass flywheel kit is bolted to the 7.3 I have the pedals mostly detached besides the 4 through bolts that go through the firewall and hold the master in place: Imgur: The most awesome images on the Internet
I have yet to aquire a pedal assembly but they seem to be common in f350s with the zf5

Then theres the driveshaft...
My stock driveshaft is a single piece 2.5" diameter steel tube 63" yoke to yoke. The a30d has a floating splined yoke on the transmission end, the zf5 has a fixed yoke, this means the shaft is going to need a telescoping section. At 63 inches and needing to get lengthened roughly 11 inches to reach the zf5 AND need to telescope that puts me well out of the cappabilities of a single piece setup.

So my plan is to find a f350 2wd extended cab diesel shaft with a carrier bearing and have a driveline shop cut it down, either that or throw 500+ bucks in their face to make it from scratch using my old shaft for parts. I got the tranny crossmember from the truck the zf5 came out of so ill likely fab that up as the carrier bearing support, stiffen as required.
 

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Hi Max!
I have a 1995 RV based on the 1992 E350 7.3L IDI with A40D, 2WD. I am following your project with interest. I have a '90 F250 4x4 with the 7.3L IDI, 5spd manual. It would really please me to have the ZF5 in the RV also. Think that's what I have in the F250. It would please me if you would take pics of anything not straight forward. Maybe when done if you are happy with your mechanic...
 

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Discussion Starter · #5 ·
Alright, well, heres where im at: Imgur: The most awesome images on the Internet

We had to cut some of the floor out including part of a floor stiffener that was right above where the new zf5 had to go, when everything is fitted up what Ill do is drop the transmission crossmember and then weld a little square box to all the parts of the floor that were exposed, hopefully this will get some of my floor stiffness back (which quite honestly I cant even tell a difference however the bus is not driving down the road yet either) The driveshaft had to be changed as the zf5 is 14 inches shorter than the a40D I have a driveline shop sending a guy out tomorrow to take some measurements and come up with a game plan, single piece or dual piece has yet to be determined but the single piece was already only 2.5" dia steel and 63" long so I assumed we would have to convert to two piece and went and yanked one out of a 2wd dually f350, as well as a tranny crossmember from a similar model van at pick n pull to support the carrier. I am a machinist so lathing up some little riser spacers is no big deal to make the crossmember I grabbed work. The driveline shop said most likely Ill go to a 3.5" single piece driveshaft but ill keep you updated with the results there.

Here's the nightmareish part tho, the pedals. I have not been able to locate an assembly which is cross compatible with my 91' e350 from any other model ford. I'm looking at a couple options one is to modify the original assembly, add my own clutch pedal and fabricate a way to mount the master cylinder to the pedal assembly without having to go through the firewall (first choice)
Modify the original assembly with the internals from another assembly I picked up on craigslist from an f250 and mount the master cylinder to the firewall as per the standard
Or just go for a universal off the shelf single clutch pedal assembly that you just bolt to the firewall wherever you want. ( Wilwood 340 1290 Clutch Brake Pedal Assembly B Mount Location B Swing | eBay like this )

So yeah, This swap isn't as easy as the brief internet research I did made it sound, its the little things that are starting to be a major drag. Just need to keep my head up and push forward. Not easy when this bus is my home away from home while at work. Had to take a week away from the project to drive down south to LA and compete on battle bots but now I'm back and ready to tackle this ****.

attached are some photos of my two pedal assemblies, one on the right with just the brake pedal is the stock unit from the bus, the one on the left is the assembly I got on craigslist pulled from the same f250 the Zf5 I installed was.
https://drive.google.com/open?id=0B7SiJiWegLAtX3ZDQy1KODZPWE0
 

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Discussion Starter · #8 ·
Makin some progress, just got the pedal assembly done:

Had to go full on custom fab for the pedals, Kinda bummed about that but its done now and that makes me almost ready to get this bastard back together.
 

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Interesting project, with several technical battles to fight. I guess with the amount of floor support you still need to remove for clearance, you will be adding steel angle or square tubing inside the cabin floor? FWIW, you can add up to 1" of body lift without causing too many other problems by machining 3" round X 1" thick pucks with @ 3/8" hole in center. That way you wouldn't need to remove too much more strength in floor. Probably enough extra thread length to maintain original body bolts too. Might be worth it for multiple reasons like keeping floor stiffness, tight seal on doghouse cover, easy injector change/access, more clearance for pedal related dilemma, etc. the fan should still line up in the shroud, but not 100% positive on that year. I thought you might have to add hand throttle or other handicapped driver type modifications to clear floor space for clutch.
I saw your previous posts and initially wondered how you were going to address 3 or 4 issues. 1) no room for clutch pedal 2) reasonably easy doghouse access while still keeping a tight seal 3) due to seating height, shifter throw might be long enough to require no console, cup holders, etc. on dog house cover. If it requires a 2 piece DH cover to be made, the additional joint is right above the loudest parts of the engine 4) are you planning on switching to a truck cluster with tach? Cheers!
 

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Discussion Starter · #10 ·
Holy **** I wish I knew about the body risers before we cut up the floor. I'm actually kinda upset about that, Just showed up to the shop and it was already done.
My plan for the square I had to cut in the floor was to weld in a plate steel box and modify the doghouse to fit it.
It might still make sense to make the risers and do that then try to repair the floor back to stock though, thanks for that tip.
 

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Holy **** I wish I knew about the body risers before we cut up the floor. I'm actually kinda upset about that, Just showed up to the shop and it was already done.
My plan for the square I had to cut in the floor was to weld in a plate steel box and modify the doghouse to fit it.
It might still make sense to make the risers and do that then try to repair the floor back to stock though, thanks for that tip.
No problem, I agree that it would be better to still do it and re-weld floor back to stock. Does that short bus have SRW or Dual? Reason I'm asking is there will be 50 comments about rollover risks (which are only proven to be true if you drive a van or bus like an idiot)! But driving with the capabilities of the vehicle in mind is really what most of us do after working hard on them. Reason I asked about the rear wheel configuration is that you could add Fred Groeske wheel spacers if the 1" lift made it feel unstable. BTW, a-lot of guys on here, including myself go with 265/75R16's. The main reason is getting the load range E. You could also stick with the 245's in E rating too. The point is that weight really piles up fast when you start out with a bus conversion and then start putting travel/personal belongings in there, stay safe! I watched your video and I applaud you for facing a unique challenge with ingenuity!
 

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Discussion Starter · #12 ·
Its a single, they make a taller bus, the super bantam, mines just the bantam, I know a guy with the super bantam and its tall enough to fully stand in one, mine isnt. I did it on purpose because I wanted to keep the height down so I can make the roof a bit heavier with solar and such.
Raising the body is gonna change things like steering column mounts and all kinds of ****, Ill play it by ear but Ill probably end up welding the box up still.
 
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