Hi all,

Long time follower/reader, first time poster. First of all, let me thank everyone at FTE, you all have help me a great deal over the past ~4 years with my beloved 7.3 and it usually only took a quick search, but I am currently experiencing an issue with my clutch that I would love some advice/input on. For background, truck is a 2001 and has ~145k mi on it, 4x4 CCLB with ZF6 and manual transfer case. Fairly stock truck, exhaust, 6637 Donaldson blue filter, TS6 chip. Unsure if I am still on the original clutch or if it was replaced prior to my ownership. Either way, prior to this week, I have never really had any issue with my clutch/transmission, apart from failed clutch hydraulics that I replaced with a complete master/slave pre-bled unit maybe ~2 years ago. That, and occasionally I would get a grind/pop-out on the first shift into OD when the truck was cold (maybe 10% of the time).

However, this week driving to work, everything is normal and I'm halfway there, push in the clutch to shift 4th to OD and instantly I could tell something with the pedal changed. At first I thought the pedal was going to get stuck to the floor, it came up with much less gusto than usual and I am instantly thinking I just lost another slave/master cyl. However the clutch pedal returned all the way. On the next shift, I could tell there was significantly less resistance in the pedal, but the clutch still disengaged and gears changed as normal. I could also tell at this point that the engagement of the pedal had changed, and the clutch wasn't grabbing until the pedal was almost all the way up, where it used to grab quite firmly around the 1/2 way mark. This symptom seems to steer me away from clutch hyd's as I would've expected a decrease in the dis-engagement of the clutch (grabbing when pedal is near the floor if it would even release at all), and seems to steer me more toward a pressure plate issue/failure. Due to the change in pedal engagement I wanted to see if I was going to start experiencing some clutch slippage so punched it pretty hard in 4th and when I got into full boost and ~2k+ RPM, I did get slippage and almost immediately the transmission popped out of 4th gear. I've never had a 4th gear pop-out before. I understand the pop-out issue is likely a result of a worn input shaft/pilot bearing. Praying this isn't too bad as I really don't want to have to rebuild/buy a refurbed ZF6... (thoughts/advice on this?)

I have driven the truck about 40-50 miles since first experiencing the issue. Slipping doesn't seem to be getting drastically worse, and I have to really try to make it slip, but its looking like I will need to yank the trans and get some eyes on the clutch assembly to see what is going on.Today I did notice some increased vibration in the powertrain/driveline, particularly at higher RPMs in the higher gears 4th/OD.

My plan is to order a Southbend clutch kit and new Hyd's from Riffraff and tear into this thing. However, before I spend $1,000 bucks and tear my truck apart in the middle of winter, I am really curious to know from the wider FTE community, does anyone have any suspicion or reason to believe that it could be something else (Master/Slave for instance) and not a pressure plate issue? Or does anyone see any holes in my differential/diagnosis that I am missing?

I already have the up-pipes done, anything else to do with the transmission out (besides find/confirm my f-ing oil leak - thinking it may be the pan gasket just below the rear main seal)?

Cheers!

 

Welcome!
I know your pain with an impending clutch job in winter. It sucked. But now i highly treasure that job.

Have you confirmed your clutch fork is not bent?
some things you said made me think maybe, others make me think not. But it's easy enough to check since you've done hydraulics before, you just remove the slave and measure the distance in to the fork.

Here's the Link to my clutch job thread, its a long read but it may give you ideas on some of the things you could do "while i am there"

If you do change the clutch get the updated clutch fork.

I like my South Bend clutch. Much firmer engagement than stock. Granted i haven't tried a Luk, but @BBslider001 recommends them, and he has extensive 7.3 experience

Make sure and do the drain tube mod. Definitely worth the minute investment of time and effort

Most times i read of people that used the South Bend Kevlar bushing had poor results, so i went with the Fitzall bearing. It's an obvious upgrade over the stock pilot bearing, and if your input shaft is damaged by a dry/failed pilot bearing it will be required anyway. Whether it's better than the bushing, may just be preference or poor installs.

I also had an unknown oil leak i was worried about, ended up being a loose rear pan bolt, tightened it up and been leak free ever since.

Take a wire wheel/brush to the starter, and mounts while you have it all off there, will help your grounds and possibly improve cold starts

EDIT:
Oh, the hardest part for me was actually the bolts on the drive shafts. They are red locktited on there, so use some heat on them, and a socket will not fit, need a good boxed end 12 point, and a cheater bar/another wrench for leverage

 

Wesley, great write up with some good tips in there - Thank you. That double-box-end wrench trick was a new one for me, and very much needed it to get my front driveshaft bolts out. I found the most difficult things on disassembly to be the top two bell housing bolts, particularly the one on the passenger side (getting these back in is going to suck). Ironically, the top two screws for the shifter boot were also a complete PITA (no room)! Even my really short Phillips screwdrivers were too tall to fit under the dash/kick panel.

I thought I would follow-up with the thread now that I have the trans out and found my issue(s), just incase anyone stumbles on this thread down the road while experiencing similar symptoms. It now makes total sense why my clutch was slipping and I started to get pop-outs...

All in all, it took me 6 hours of labor to get the trans out, going pretty slow and taking plenty of beer breaks! I had a shop quote me 7hrs for a full clutch job a couple years back, so I am well off of flat-rate, but not bad for a shade-tree mechanic pulling their first ZF6. I will say other than the weight of the ZF, it had to be one of the easier transmissions ive removed.

I think I am definitely going to do the drain tube mod (assume this is for the valley drain) need to do a tad bit of research on how others have done it. It also appears I have an input shaft leak, so going to be ordering a new seal and taking care of that. I have also been thinking that the pilot bearing failure might be a result of too much flexing between the trans/engine, so new trans/motor mounts will be getting ordered shortly. I have seen some guys can do these (and the oil pan gasket), just by pulling the fan shroud and jacking the engine up. I will let everyone know how this goes...



Fitting my CCLB into the garage was a bit comical, but it was into the teens/single-digits this week, and snowing, so there is no way I was going to do this outside!

Got the trans out alone, many people recommend an extra set of hands, and they definitely would've helped, but it is doable alone - be careful! We'll see how the install goes without help...

Who needs a pilot bearing anyways... Also, it is hard to tell from this picture, but at about the 4 o'clock position I collapsed abut 4 teeth on the pressure plate.

Better view of the pressure plate damage.

I am actually shocked I was able to drive this truck with the pressure plate and pilot in this condition. I have actually experienced both of these failures separately on two C5 Corvettes. In those two cases, the pilot failure resulted in significant drag on the input shaft and made it almost impossible to shift, and the pressure plate failure resulted in me being stuck in gear (thankfully 1st) and I was only 2 blocks from home, so I was able to limp it into the garage. Built Ford Tough!

 

Ahh, another vette guy wave

For the top bellhousing bolts get some socket extensions and ujoints and feel your way onto the bolts thru the shifter hole from inside the cab. Granted i have smallish hands & wrists @ 5'10" 148# , may not work as well if you have man hands.

 

With a blown out input bearing and a disintegrated T.O. bearing, my ride still found the gears. Just more resistance in the pedal...
might as well order up the new improved clutchfork since your this far along.
When reinstalling, i found massaging the drip line where the body mates, makes for an easy trans install...aka, deadblow'n it.
Inspect the input shaft nipple. If torn up, the fitzall kit works wonders. Find them on ebay.
other than that, use the long trans bolts to align trans to motor, then back them out and use the correct bolts....cant imagine doing this job with transfer case still intact.

 

I guess i was lazy when i did that route too and didn't want to deal with disconnecting it and reconnecting, vs just moving the jack back 5" more inches

 

For install, be sure to get a couple of spare bolts from the trans to the engine block. Cut the heads off, round them off a little, and grind a slot for a flat screwdriver to turn. Thread one in loosely on each side to use as guide pins for the install. It'll help immensely when you're trying to line up the input shaft with the pilot bearing.

 

^^^^^
This. I listed those metric bolt size/threads in my thread above, get as long of bolts as you can possibly find, if you have a lathe chuck them up and turn down the heads instead of just cutting them off, you'll want that extra 1/4 inch of length. Will be worth their weight in gold when you go to line it all back up

 

I expect that input shaft is TOAST. At a minimum, you will need a repair kit like fitzall or an oilite bronze (self lubricating) bushing and repair sleeve. OE bearing or Kevlar bushing won’t last long on a damaged shaft. You can PM me for more details.




There is no good reason NOT to extend the valley drain to the bottom of bell housing. You’ll need a 1/2” 90* sweat fitting and some 1/2” soft copper tubing. The 90* fitting will need trimmed to fit behind rear engine cover. Doesn’t hurt to seal it in with RTV.




The motor mounts have nothing to do with pilot bearing.

I would be concerned about the condition of the input bearing if the seal is compromised.

I like to use long bolts in the top (2) holes to help line everything up when going back together. Old head bolts are PERFECT for this.

 

[QUOTE=SkySkiJason;19060240]I expect that input shaft is TOAST. At a minimum, you will need a repair kit like fitzall or an oilite bronze (self lubricating) bushing and repair sleeve. OE bearing or Kevlar bushing won’t last long on a damaged shaft. You can PM me for more details.

I think I read that you cant PM until 5 posts, not sure if that is still true... almost there!

Oh yes, it is toast without question. It looks like the pilot may have failed while ago because the input shaft has some pretty good/smooth wear to it. I ordered up a repair kit like fitzall and this one seems real nice but the more I think about it the less I like the idea of putting another needle bearing in there - mostly because I have some very slight play in the input shaft which I think will grenade those tiny rollers in short order if I re-install without rebuilding the trans or replacing the input bearing. We are talking less than 1/16" total deflection at the end of the shaft vertically, half of that side-side and no visible in/out. I have seen the bronze bushings/hardened sleeves you had made in a tread I stumbled across while researching for this job and was wondering if a more solid option like that for the end of the input shaft would let me nurse the trans/input bearing along before I get a rebuild.

I know I've read "any play at all" = rebuild... but what is the absolute worst that can happen? I end up needing a rebuild/t transmission, which I already need?

I don't drive the truck that much maybe ~7-8k mi/year (drive it maybe 2-3 days a week), so if I can nurse the trans for even another 30-40k (or more) this way, we are talking several years before I am doing a rebuild. Am I crazy for wanting to/thinking I can put it off? If so just tell me and I guess Ill get to researching vendors...

Cheers for everyones help/knowledge along this journey!

 

I only got 10k miles out of a Kevlar bushing when my ZF6 had play in input bearing. I would like to think oilite bronze would be better, but I don’t know.

I’ve used All Star Standard Trans in Tampa, FL for several ZF6’s now. Great folks and family biz I’ve used for 25yrs. (About $1950 & $150 shipping)

 

Guess in addition to 5 posts, must also have been a member for 10 days to send a PM. Jason, if there is any way I can get in contact with you to order a sleeve and custom oversize oil lite that would be great!

 

i got this?

 

Don't quote me on this, but I think the minimum post count is 10 for PM's.

 

Its telling me I have to have a minimum of 5 posts, and be a member of the forum for 10 days prior to sending PM's. Can you shoot me an email?