zf6 cold shift

[greenskeeper]

Odd problem I think.

Fluid is Mobil 1 synthetic ATF just changed 7k ago

The first 2 or 3 gear changes going from 2nd to 3rd gear when the truck is first driven result in a "crunch" as the shifter goes into 3rd. I wouldn't call it a grinding sound.

This will happen ONLY during the first 2 or 3 gear changes from 2nd to 3rd, after that it shifts fine. Downshifting from 4th to 3rd is fine.

I replaced the bushing at the clutch pedal and ordered the heim joint repair. I'll have to check how old the master/slave cylinders are, although I did try pumping the clutch a bunch of times before driving with no change.

When cold, shifting from 1 to 2, then 4 to 3 (with clutch depressed) does not crunch into 3rd gear.

I would think if it was a clutch/hydraulic/syncro problem it would happen all of the time.

I generally park the truck by reversing into a spot and leaving the transmission in 2nd gear. Could moving into Reverse somehow put 3rd gear "out of alignment" or something? I'm not sure how this transmission is built. I am going to try to park so that I don't back into the spot and see if I get the 3rd gear crunch for the first couple of shifts.

 

[79jasper]

When you say 1, are you meaning "L?"
Does sound odd though.

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[greenskeeper]

1st gear, not L. Only does it after reversing, can eliminate the crunch on the first 3rd gear shift by going 2-4-3 before letting the clutch out, after that first shift it doesn't do it again until I use reverse

 

[79jasper]

That's really strange. Maybe something with the detents in the shift tower.

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[War Wagon]

How new or how good is the clutch? Is it hard to push?

 

[greenskeeper]

How new or how good is the clutch? Is it hard to push?

clutch has 10k miles on it. clutch works smoothly and no issues except for the very first 3rd gear shift after using reverse. If I do the 2-4-3 before releasing the clutch it doesn't crunch into 3rd gear. After that all gears including 3rd shift very easily.

new shifter guides have been ordered.

 

[79jasper]

If not that, about the only thing left would be the synchros.

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[greenskeeper]

Wouldn't a bad start synchro act up all the time and not just after using reverse during the first 3rd gear engagement, shifting fine after that?

 

[79jasper]

Would seem like it.

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[greenskeeper]

Removed the shifter to inspect the roll pin.....in place. Put everything back together and now it shifts fine all the time....I have no idea what changed.

 

[79jasper]

Well, at least it's fixed. Lol

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[greenskeeper]

Well the 3rd gear problem is back again. Always only the first or maybe the 2nd shift into 3rd.

I am going to try the cheapest solution and replace the master/slave cylinder on the clutch.

Did Ford come out with an upgraded version? Any suggestions aftermarket as I don't want chinese junk.

 

[greenskeeper]

Install a new from FORD master/slave cylinder pre-bled assembly. Almost a no problem install except the slave cylinder can be turned past the stop if not careful. I set it in the middle as best I can tell, must be something unique to the E99s or just my crappy luck. Almost like there should be a spacing ring or something to hold the tabs closer to the bell housing.

First drive after the change...no 3rd gear problem. Clutch seems much higher in the pedal and the shifting is a lot smoother when getting on and off the clutch.

Tomorrow will be a test when the truck is stone cold from siting overnight.

 

[greenskeeper]

clutch control is better but the early shift crunch is still there, perhaps not as bad.

 

[79jasper]

Seems like it would almost have to be mechanical inside the trans at this point.
I saw the other thread. I'm not sure. Don't think we have many zf6 owners here. Lol. I'll take a look around though.

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