ZF trans question
Thread Starter
Intermediate
Joined: May 2002
Posts: 37
Likes: 0
From: Kalamazoo MI
ZF trans question
Recently my 1-2 shift has been grinding like crazy. It does it worse once the car is warmed up. 75% of the time it shifts fine, but the other 25% I have to double clutch it to get it to go into second gear, or it grinds like mad, and wont go into second. Anybody have any ideas on what the prob is? Thanks for the any help.
Pro
Joined: Jul 2002
Posts: 589
Likes: 1
From: Tucker GA
Re: ZF trans question (93LT1Vette)
A. Clutch not fully disengaging
Check fluid level
Check for broken/worn parts in clutch (fork, throwout bearing, etc.)
B. Check Fluid level in transmission.
Would not hurt to change it
C. Linkage alignment (very rare)
D. Synchro's damaged
Get out your wallet................
Visit: http://www.zfdoc.com/
Good luck.
Bob
Check fluid level
Check for broken/worn parts in clutch (fork, throwout bearing, etc.)
B. Check Fluid level in transmission.
Would not hurt to change it
C. Linkage alignment (very rare)
D. Synchro's damaged
Get out your wallet................
Visit: http://www.zfdoc.com/
Good luck.
Bob
Thread Starter
Intermediate
Joined: May 2002
Posts: 37
Likes: 0
From: Kalamazoo MI
Re: ZF trans question (93LT1Vette)
The car has 51,000 miles. I never drag race it, and usually just baby it through the gears. I had the car totally serviced when I got it, including a fluid change using the GM syncromesh trans fluid, so I know its right up on fluid, and its fresh too...... Thanks for the info, I am pretty clueless about ZF trannies.
Racer
Joined: Sep 2002
Posts: 270
Likes: 1
From: Portland OR
Re: ZF trans question (93LT1Vette)
If you have to "double clutch", it sounds like you may be trying to shift it too quickly. Make sure the clutch pedal is to the floor throughout the shift. Corvette clutches are poorly designed in that there is way too much distance between the point where transmission is disengaged from the engine and where the synchros allow a "clean" shift.
If the fluid were the problem, all gears would be tough to shift into, especially reverse when cold (try that and see if that is problematic as well).
If you have always owned the car and babied it through the gears, then the synchros should be fine.
If you are the second owner or later, it is possible that a previous owner ignored the whole "use the clutch when shifting" system and destroyed the synchro, in which case, as the previous post notes, $$$.
Also, if the problem has only occured since having the fluid changed, I would immediately change fluid.(refer to search section for fluid reccomendations - I prefer the castrol synthetic from the BMW dealer). Good luck. :steering:
If the fluid were the problem, all gears would be tough to shift into, especially reverse when cold (try that and see if that is problematic as well).
If you have always owned the car and babied it through the gears, then the synchros should be fine.
If you are the second owner or later, it is possible that a previous owner ignored the whole "use the clutch when shifting" system and destroyed the synchro, in which case, as the previous post notes, $$$.
Also, if the problem has only occured since having the fluid changed, I would immediately change fluid.(refer to search section for fluid reccomendations - I prefer the castrol synthetic from the BMW dealer). Good luck. :steering:
Drifting
Joined: Jul 2001
Posts: 1,296
Likes: 0
From: Largo Florida
Re: ZF trans question (Darkness)
Sounds like your hydraulics are bad. I would replace both the clutch master cylinder and slave. Very cheap insurance for a $2500 rebuild!
Read ZF Doc's website and call him if you have any questions. He is real helpful.
Read ZF Doc's website and call him if you have any questions. He is real helpful.
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Race Director
Joined: Sep 2002
Posts: 17,881
Likes: 25
From: The third orange grove on the left
Re: ZF trans question (93LT1Vette)
If your 2nd gear synchronizer is going bad you will typically get a grinding noise when you are shifting at higher rpm's. When your clutch system isn't working properly the synchronizers are working like crazy to make up for it and it leads to early failure.
