im cheering u on, u just cant hear me ....

 

Thanks, helps that someone is interested.

I got back to it eventually and reassembled the mainshaft with the new parts. Good enough to tonight. I'll probably check preload and install in the cases tomorrow, then in the truck hopefully Tuesday if I'm ambitious to do it solo as it'll be warm, or by the weekend if I want to wait for another pair of hands.

 

I found my problem with 2nd gear popping out. 1-2 shift fork was very worn measuring at .274" across the pads. New fork measures .300" New slider measures .315" in the groove, old slider measures .320". So the old fork had .046" of slop. Mind you the gear teeth are only about .100" deep for engagement. Likely not enough throw to fully engage 2nd consistently so it would pop out under load. The new fork and slider will only have .015" of clearance, hopefully allowing full engagement of the slider on the gear.

2nd gear teeth didn't really look bad, only very slightly rounded at the top. Nothing like reverse being very worn and abused. It's not a grade A part anymore but likely perfectly serviceable absent other parts being worn out.

 

I didn't spend as much time as I'd have liked on this tonight. I was going to just roll with however it fell if the mainshaft was tight but there's a few thou endplay so I need to shim the mainshaft in the case. I was hoping to avoid this as this front case has some wear and the race is no longer a tight press fit, I installed the race with Loctite 640 bearing and sleeve retainer, which has held up fine. I'll heat to remove that, shim to spec, and reinstall the race with Loctite 640.

In the interim, I learned a new trick. Instead of installing the big heavy main and counter shafts with rails into the rear case, flip it over and install the aluminum rear case onto the heavy assembly. Not sure why this never occurred to me before, but it sure made this part easier.

 

Mainshaft had .007" end play, added .010" shim to the pack to bring it up to .003" preload. I was worried removing the front race for this as I had hit the case with a center punch many times where the race seats and installed the race with Loctite 640 bearing and sleeve retainer. I was worried about damaging the case and viability after another install and removal of the race. I heated the case with a torch for a couple minutes working around the race, then pulled with a slide hammer. It came out uneventfully but felt reasonably tight. I cleaned the parts and reinstalled with a healthy dose of Loctite 640, it took some effort to drive the race in and I could not spin it by hand. Should be good to run in 24 hours after this cures.

I still need to install one PTO cover and the 3 detent springs and plugs, but that's quick and easy. Hoping this is the last time I'm in this transmission for a long time.

 

Wrapped this up today. Put the trans in solo this morning, it was surprisingly easy. Later after dinner I couldn't just leave it be, so banged out the transfer case, rear shaft, and shifter parts. Overfilled with 4 quarts Mobil1 synthetic ATF as usual. Started it up and trans is quiet. I did not go for a test drive, but it goes through the gears fine with the transfer case in neutral and moved forward and back. A little stiff engaging 1/2 or reverse from a stop sometimes but it'll take a few shifts for the new blocking rings to wear into the new gears. I will test drive tomorrow, if all is well I'll throw the front shaft and skid plate back on and call it done.

 

im with UPS its christmas rush, finally got a night free i see ive missed a lot here

looks all pretty an clean from the outside! car show clean!

flipping the rear housing, over the gear set clever just a little trickier getting the shift rails to line up.

the manual tells me never use a sealer between case halves for fear of throuing off the mainshat pre load; comments? does that work 4 u? using sealer

every time i pull a race it makes me a bit nervous, wondering if it will go back in as tightly as it should..

i hafta ask: earlier when i mentioned the oil passage , that is blocked off , did u happen to look at that when you had your case off? i should have mentioned a few days back but have been occupied

 

I've never had an issue using sealer, I would fear a leak if I did not use it. You assemble the cases with no sealant? Ever had a leak? I use anaerobic sealer which I thought was what ZF called for, not RTV. I do check that I can't rock the input shaft after torqueing the case bolts and check mainshaft endplay. I've been into ZF5s a bunch of times and never found endplay after assembly, though I try to set them towards the tighter end of acceptable preload where possible.

I did not check that oil passage. I do have a S5-47 diesel front case sitting in the garage. I'll check that and take pictures. There is a rail inside the front case that collect oil slung by the gears and discharges it in front of the input shaft bearing, this lubricates the input shaft bearing and pocket bearing. I have not paid particular attention to what's on the bellhousing side in that area though I know there is a freeze plug in the bellhousing area.

 

yes factory service tell us to use no sealer between case halves. i thot it odd, but i took min e apart, and, no sealer.

 

After driving a bit 1-2 has seemed to wear in and has gotten much easier. I suspect this is in part the 2nd gear synchro wearing in to seat better on the gear cone and also the new 1-2 shift rail getting worn into the detent. I probably should have taken a file to the aftermarket 1-2 rail to smooth the edges of the detents, but it seems fine. Has not popped out of 2nd or given any issues other than being a little stiff going in initially.

Reverse is still problematic, maybe because I use it less and it has not had time to wear in the synchro. I'm also curious about the different design of the blocking ring. The grooves are radial rather than perpendicular to the cone, this is different than any other blocking rings I've used before. Reverse has popped out a time or two after moving the truck a bit, but does did not grind when it popped out as it did previously. It just pops out straight to neutral. It is still stiff to get into reverse and may take a couple tries, it feels like the blocking ring has overtraveled and is not guiding the slider onto the gear teeth.

It goes into reverse seemingly perfectly every time if I use 4th gear synchro first. After noticing that I tried waiting a few seconds with the clutch in before engaging reverse, and it tends to go in smoothly and easily if I wait for the countershaft and reverse gear to slow or stop moving. If this proves to be sufficient then that's a lot better than it was before, and maybe a sign the reverse synchro needs time to wear in and grab the gear cone better..

 

i vote for driving a bit more.
i might be imagining things but i recall the new 94's having similar issues until loosened up some. the other note, i wonder if the type of ATF used might have an effect on performance..
there was a transmission recently where i read that the new gl-5 rating was improper in that for this old design was an oil too slippery for the synchros, so if true and not internet speculation, there may be value in considering this.

our trans need dex 3 right? i wonder if a shot of lube guard might be useful

 

I'll keep driving it, being careful engaging reverse to avoid popping out or being hard on the fork. Hopefully it wears in and shifts nicer eventually. I am regretting not measuring the gap for the fork in the new slider and the fork pads to verify a reasonably but not excessive clearance. Worn fork could cause these issues, but it really shouldn't be terribly worn as it's got very low miles on it.

I'm using Mobil1 synthetic ATF (https://mobiloil.com/en/automatic-tr.../synthetic-atf). The ZF specs synthetic for the ZF5 in a diesel application, though the internals are effectively identical to a small or big block trans. Is there a better oil than this to use? This is just what is easily available locally. I could try regular dino ATF for a while to see if the reverse synchro grabs any better.

 

How much was the rear housing? Did you get it from Midwest?

And did you use the 47 gear set?

 

$369.95 on eBay. I did use the S5-47 internals.

 

SO....is she holding together?