Manual Tranny Guru's: Is this bad??
07-12-2007, 05:55 PM
#3
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St. Jude Donor '04-'05-'06-'07
Some play there is normal. The front of the input shaft on a manual trans is of course stabilized with a pilot bushing or bearing. I've no experience with the ZF trans used in C4s but have worked on hundreds of manuals over the years. From basic 3 speed manuals in old cars to 13 speed HD truck trannys. This play appears to be a bit excessive to me. How does the input bearing feel, is there any roughness to it? Has the trans ever been run very low on oil? On many manuals, the input bearing is generally an early casualty of low oil.
07-12-2007, 07:29 PM
#4
Burning Brakes
Thread Starter
Used vehicle, so oil level is unkknown. It was OK when i bought it. Anyway, the clutch chatters, I get a grind when going to 5th, Reverse. The tranny whines when in motion. (varying with engine speed)
07-12-2007, 07:52 PM
#5
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Case,
That's WAY loose! Bearing is shot for sure. Perhaps even the case and shaft (if bearing turned).
My ZF was noisy at cruise so when I pulled it (for clutch) my shaft had MAYBE 1/16" 'play' at the pilot end. Still suspecting the bearing I searched all suppliers and found it's a propriatary made/sold only by ZF. ZF only sells it as a 'bearing kit' (3 or 4 bearings and a few seals I think) only and quoted me a price of around $700.00
I replaced the pilot (although old one was still good) and stuffed it back in. Strangley, the whine disappeared. (I always suspected it was caused by the case lining up with the bellhousing.)
Anyway.....should I ever need to repair/rebuild my ZF......I'll simply buy a new one. Typically they're around $1,500 on ebay.....and even come with a warranty.
That's WAY loose! Bearing is shot for sure. Perhaps even the case and shaft (if bearing turned).
My ZF was noisy at cruise so when I pulled it (for clutch) my shaft had MAYBE 1/16" 'play' at the pilot end. Still suspecting the bearing I searched all suppliers and found it's a propriatary made/sold only by ZF. ZF only sells it as a 'bearing kit' (3 or 4 bearings and a few seals I think) only and quoted me a price of around $700.00
I replaced the pilot (although old one was still good) and stuffed it back in. Strangley, the whine disappeared. (I always suspected it was caused by the case lining up with the bellhousing.)
Anyway.....should I ever need to repair/rebuild my ZF......I'll simply buy a new one. Typically they're around $1,500 on ebay.....and even come with a warranty.
07-12-2007, 08:26 PM
#6
Burning Brakes
Thread Starter
I think this may be the source of most of my drivetrain woes. This would also explain why when I shift from neutral to reverse I get a grinding noise. I need to replace the speedometer drive gear with new ratio anyway...
07-12-2007, 08:52 PM
#7
Team Owner
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Location: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
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I would tell you based on the couple of trannys I've wiggled the input shaft on (damn that didn't sound right 
) but I can't view that vid format.
) but I can't view that vid format.
07-13-2007, 02:49 AM
#10
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Even 1/8" is too much IMO!What kills these bearings? Bent bellhousing? Loose tranny? Might be worth checking the alignment of the bellhousing on that car before replacing the trans.