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Zf6 grinds in 3rd only

3K views 6 replies 4 participants last post by  Stavi 
#1 ·
Hello all,
My 6 speed grinds when upshifting into 3rd (3 on the diagram) gear but not while downshifting. It won't grind if I shift under 1,000 engine rpms. The grinding varies. It's usually a hard clunk and minor grind like it's just slipping into gear but still crunching. Sometimes it's straight thrashing noise. Could it be my slave cylinder?
 
#2 ·
I had a 99 ram 6 speed when I was 20 that ground going up or down into 3rd. Double clutching fixed the issue. My brother was certain that it was the synchronizer, but I never fixed it. Sorry that's the breadth of my knowledge.
 
#3 ·
Drain the fluid and fill it with Pennzoil syncromesh.
 
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#4 ·
Sorry for the late reply. I flushed the old fluid out for new Valvoline Maxlife ATF. It still grinds, but I find that a quick blip of the throttle between shifts does seem to help a lot. It doesn't always help, but it's a lot less now.
 
#5 ·
See post #3
 
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