Odd ZF6 shifting issue
#1
Intermediate
Thread Starter
Odd ZF6 shifting issue
Hello all,
I am the owner of a 92 c4 with the zf6 manual transmission. Sometimes, after sitting at a light, stop sign, etc for a period of time the car will not go into first. Ergo, sitting there in neutral, clutch out, push the clutch in as you do, go to shift into first and it just feels like there is a wall there. No grinding, no chattering, just a wall. Letting the clutch out briefly and pushing it back in solves the problem and allows me to shift into first. This doesn't seem normal and I was thinking it had something to do with the clutch hydraulics after doing some reading, even though they had been replaced at some point in the cars lifetime.
Finn
I am the owner of a 92 c4 with the zf6 manual transmission. Sometimes, after sitting at a light, stop sign, etc for a period of time the car will not go into first. Ergo, sitting there in neutral, clutch out, push the clutch in as you do, go to shift into first and it just feels like there is a wall there. No grinding, no chattering, just a wall. Letting the clutch out briefly and pushing it back in solves the problem and allows me to shift into first. This doesn't seem normal and I was thinking it had something to do with the clutch hydraulics after doing some reading, even though they had been replaced at some point in the cars lifetime.
Finn
#2
Drifting
Gonna go with clutch hydraulics as well. You can try bleeding (though that'll be a lot of fun since the bleed valve is on the bottom of the slave cylinder instead of the top, so either you remove the slave cylinder from the transmission and tilt it so the bleeder is the highest point, or use a Mityvac/Phoenix power bleeder to reverse bleed it), and if that doesn't work, then it's time to replace the master cylinder and slave cylinder. Don't do one or the other, do both.
Best of luck!
Best of luck!
#5
If doing that work is not an option right now you can always do the little work around. When sitting at the light or wherever and it's time to go put the clutch in like normal slide it into 2nd then go to 1st. I used to have al Alfa Romeo and this was the common shifting technique for that car from a stand still. If you try for 1st without 2nd you hit the wall, every time. 2nd then 1st and its like butter. Something to do with clearing the alignment. I drove like this for several years, early 90s, and still have that habit today. My 6spd doesn't require me to do this but when I do getting to 1st is so much smoother. My brother drove his Alfa the same way, same car but different year model, he also shifts this way. My dad drove 18 wheelers for 40 years and he also shifted this way.
#8
Intermediate
Thread Starter
#9
Drifting
Does the car feel like it is creeping or engine bogging slightly even with clutch in?
Do you ever have trouble with the car off getting it into 1st (if this happens again you could shut the car off and see if it then slides into gear)?
If no issue with engine off then the clutch hydraulics are suspect and one of a very few ways to kill the ZF trans is to drive it this way.
Check the fluid reservoir as others have suggested, and you shouldn’t need to bleed it other than using the ranger method...at least in my case (had similar happen to me due to leaking master).
Only other idea would be something with the shift mechanism if hydraulics check out.
Do you ever have trouble with the car off getting it into 1st (if this happens again you could shut the car off and see if it then slides into gear)?
If no issue with engine off then the clutch hydraulics are suspect and one of a very few ways to kill the ZF trans is to drive it this way.
Check the fluid reservoir as others have suggested, and you shouldn’t need to bleed it other than using the ranger method...at least in my case (had similar happen to me due to leaking master).
Only other idea would be something with the shift mechanism if hydraulics check out.
#10
Melting Slicks
This is normal. Occasionally these transmissions won't go into first gear on the first try. So don't mess with the hydraulics just yet, although it is a good idea to check the hydraulic fluid/condition and change the synchromesh every 15-20k. This snippet is from the 1995 owner's manual:
Last edited by DGXR; 06-11-2021 at 02:25 PM.
#11
Drifting
Wow - didn't about know that in the manual... Perhaps I just do that naturally without thinking (i.e. whenever I come to a complete stop I slide it into neutral, slide the shifter side to side and let up on the clutch then maybe again if it feels tight when ready to go into first)...
OP stated he was letting up on the clutch in neutral and then having issues getting into first after then depressing the clutch to go into first...which would be the proper method...Maybe having to do that *again* is considered normal??? Borderline clutch hydraulics would have a similar behavior so worth confirming there is nothing amiss there.
OP stated he was letting up on the clutch in neutral and then having issues getting into first after then depressing the clutch to go into first...which would be the proper method...Maybe having to do that *again* is considered normal??? Borderline clutch hydraulics would have a similar behavior so worth confirming there is nothing amiss there.
#12
Melting Slicks
Basically this what the manual is saying: If you can't get it into first, let up on the clutch, then push in the clutch and try it again.
My car does this occasionally and I know that the hydraulics are working fine.
My car does this occasionally and I know that the hydraulics are working fine.
#13
Drifting
I think what the OP is describing is pretty typical of manual transmissions. I have owned and driven lots of manual trans cars that act this way. The habit I devolped over time is to push in the clutch, put it in second and then into first and release. Anytime I need to get started I do it this way. Getting into reverse can be difficult too so I always put it in first or second before putting it into reverse.
My current setup in my 84 is a TKO 600 that has had 2-3-4 faceplated. It can be a bit tricky to drive. My habit doesn't work because 2-3-4 have no synchros, just dog rings. If you put it into 2-3-4 while standing still it smashes into that gear, makes hella racket, and scares the **** out of you. So I just double or triple pump the clutch before putting it into first in these situations now.
My current setup in my 84 is a TKO 600 that has had 2-3-4 faceplated. It can be a bit tricky to drive. My habit doesn't work because 2-3-4 have no synchros, just dog rings. If you put it into 2-3-4 while standing still it smashes into that gear, makes hella racket, and scares the **** out of you. So I just double or triple pump the clutch before putting it into first in these situations now.
Last edited by Krusty84; 06-11-2021 at 04:58 PM.
#14
Intermediate
Thread Starter
This is normal. Occasionally these transmissions won't go into first gear on the first try. So don't mess with the hydraulics just yet, although it is a good idea to check the hydraulic fluid/condition and change the synchromesh every 15-20k. This snippet is from the 1995 owner's manual:
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Furias15x (06-12-2021)
#17
Drifting