Well, the ZF5 got pissed on the way to work and I had to pull over and decided to have a friend drag me home to avoid more damage. I was bummed. I bought the trans freshly rebuilt from a shop that the owner was retiring. Everything appeared in good working order and I got 12,000 miles without issue until 2 weeks ago.

Lately, driving to work on really cold mornings, I would hear a quick "zing" noise from what I thought was the trans, but it would only happen once, real quick and only on mornings when the truck was cold, the air temp was sub-30F and only on the interstate in OD @ 75mph. This would only happen every 5th time under only those conditions, making it real hard to diagnose the problem. Well 2 weeks ago, with an air temp of 24F, it happened 10 miles into my commute, then again and again every 1/8 mile. It didn't take long before everytime I heard the noise, you could feel the truck bog down.

I popped the t-case in neutral and coasted off the interstate. By the time I got onto the frontage road, the trans was pissed and could stall the engine when letting the clutch out with both trans and t-case in neutral. I was guessing either input bearing or secondary shaft bearings.

By the time my friend showed up, things had cooled off and were operating normal again. Not to risk it, we strapped it and tow it home. I dropped the trans and last week with a friend in town, we cracked the case open. I was relieved to find nothing major like giant metal flakes. The fluid was a little dark and the magnet seem to have an excess of sludge on it.

by , on Flickr


We pulled the gear cluster and at a glance, things looked to be in good condition. Main shaft bearing were good, but counter-shaft bearings looked a little dull with signs of high axial loading.
by , on Flickr

by , on Flickr

by , on Flickr


This was my suspicion all along. Reading the S5-42 service manual, proper preload is important to the bearings due to case expansion. I bought a 3-jaw internal puller and yanked both bearing cups. The only shim was the original single spacer the factory would have used after performing statistical analysis of the mfg tolerance stacks. Best I can tell, when the thing was rebuilt, it was just ped back together and no one checked preload. With a cold case, the aluminum would have contracted tighter on the bearings until the ATF could no longer penetrate the space between the rollers and the bearings went dry.

SO, now bearings are on order and I get to run through the pre-load procedure.

I know this isn't fun for you but I always appreciate your engineering perspective on problems and learn as much as I can, I'm glad it's repairable.

x3. I'm glad your brain is in this club.

Thanks guys.

On the plus side:

1) I'm very happy with how I put everything together. Pulling the transmission was the easiest pull I have done. I only used 3 sockets, 3 end wrenches, an allen, a screwdriver, and a trans jack to remove the exhaust, driveshafts, t-case and trans.

2) The ZF5 is very serviceable. Hands down the easiest teardown I have done on a manual. Most light and mini truck transmissions require partial disassembly of the gear cluster to break them down. Usually 5th and reverse gears are behind a partition within the case. The ZF splits the case very easy and the entire gear cluster is removed as one unit. There are a number of special tools require for a full break down, but that is nothing unique for a transmission.

Slow progress lately, but moving forward.

I ordered bearings and seals. Pushed the new bearings on tonight. I had a serious when I priced out the recommended bearing puller from Ford. $1700!!!

So I did what everyone else does:
by , on Flickr

by , on Flickr

by , on Flickr

by , on Flickr




After cleaning the case mating surfaces thoroughly, I dropped in the counter-shaft and laid the housings together. I went about measuring preload/clearance backwards, but I figured there was a good chance the spacer was too big. Using shims, I evened the gap all the way around the housing halves and spun the shaft a few times to get it seated well. Feeler gage was telling me that I still have .0050"-.0055" gap, meaning there was about .002" too much preload on the shaft. I will take it back apart tomorrow and use the lathe and a Dremel as a make-shift surface grinder and take ~.003-.004" off the spacer and push the pre-load into the middle of its allowable range.
by , on Flickr

by , on Flickr

Love the bearing puller, I wonder if my diff bearing puller could have been able to do the work. Question, is the preload checked with only the case weight "loading" the bearing?

Cool, I'll have to pull my PTO cover next time I work on my drivetrain and take a measurement.

Honestly, I'm surprised it had a problem. Bearings are so exact, they are essentially interchangeable, even between manufacturers without issue. Tolerances are plus/minus .00025". Even with two bearings, tolerance stack is still minimal. The OE bearings had to have been on one end of the tolerance band and the new bearings on the other AND the transmission would have been setup with near maximum preload.

At least that's how I see it.

Statistically, most should be fine, but the right procedure is to check lash/preload every time.

A little catch up:

Before putting the transmission back in, I took a detour and designed/machined an AN quick disconnect fitting to match the factory Ford hydraulic clutch fitting.
by , on Flickr

by , on Flickr

by , on Flickr

by , on Flickr

by , on Flickr


Then, recently, installed a front sway bar
by , on Flickr

by , on Flickr

by , on Flickr

by , on Flickr

Jerk!


Sent from my iPhone using Tapatalk

And swapped in smaller injectors, which fixed an uneven fueling issue at WOT
by , on Flickr

by , on Flickr




...a 2nd 1BAR baro sensor so the computer can comp for altitude on the fly (vs at startup). This isn't finished yet, but I needed it functional before heading up to the mountains. I'll make a nice housing later.
by , on Flickr


I also bought some nice roll cage padding at Todd Z's suggestion. This stuff is dual durometer and SFI rated.
by , on Flickr



Then added a P3 brake controller, which required opening up 3/4 of the wiring harness.
by , on Flickr


and cleaned up some wiring
by , on Flickr

All so I could do this safely:
by , on Flickr

I just mean that I hate how capable you are if making your own stuff...


Sent from my iPhone using Tapatalk

Nice custom upgrades! How much weight is that trailer and how's it tow with the bronco? That front sway bar sure is beefy

Serious Thumbs Up! Especially the camping pic.

Wait, you're supposed to drive them? Looks great, esp like the new camper.

Sent from my SM-N920V using Tapatalk

Some really nice upgrades! Do you pl an to disconnect to the way bar for offroading?

This week I got around to re-hosting many of the pictures that were lost on this thread thanks to the Photobucket debacle.

It's been a year and a half now, so I'm happy to get the build pictures back.

I had been fighting a weird glitch with the ignition system and replaced darn near every component trying to fix it, including the computer. The only thing left was the ignition trigger in the MSD. Looking for more accuracy and moving towards getting rid of the distributor, I designed and machined a 36-1 Ford-style trigger wheel and sensor bracket.

by , on Flickr

by , on Flickr

by , on Flickr

by , on Flickr

by , on Flickr

by , on Flickr

by , on Flickr

by , on Flickr

I got a new steering wheel for my birthday.

by , on Flickr


Since then, I have been working on refining little things. I decided to switch intake manifolds and ordered one from Edelbrook on Jun 3rd.

After many, many backorder notices, missed dates and a lot of back and forth, they finally delivered it after I got home from SEMA, 5 MONTHS after the order was placed. It has been extremely frustrating and forced me to take stock of where I was in the project and what was left to do.

Besides a new winch bumper and some minor items, the biggest to-dos revolved around engine upgrades like a serpentine belt system, further EFI refinement and adding a catalytic converter and an aux fuel tank. It was still of a lot of work and even after all that I would have a vehicle that only gets 14 mpg at best. I have had a long term plan to go diesel and while at SEMA I took a second look at Cummins' crate diesel engine.

Cummins recently improved the engine calibration and pushed the little R2.8 to 310 lb-ft of torque. This made it a lot more appealing, especially since it weighs the same as the 351W and has an acceptable RPM range, which means no spring or gear changes. After a few nights calculating return on investment and selling my motorcycle a month ago, I decided to pull the trigger.

Delivered
by , on Flickr

by , on Flickr

Unpacking
by , on Flickr

by , on Flickr

by , on Flickr

I love this line: "I designed and machined a 36-1 Ford-style trigger wheel and sensor bracket." You say that as if it is as easy as making a PBJ sandwich. Love watching your build. Wish I had a tenth of your smarts.

Sent from my Pixel 2 using Tapatalk

Did you see the R2.8 in the rolling chassis at SEMA?

The 2.8 is very cool, I look forward to seeing your progress and hear your reviews. That’s a motor swap I’ve considered as well.


Sent from my iPhone using Tapatalk