[Z06] Tranny/shifting problems: Experts please advise
Thread Starter
Melting Slicks
Joined: Dec 2006
Posts: 2,186
Likes: 2
From: Woodinville WA
Tranny/shifting problems: Experts please advise
about 1,400 miles ago I had the tranny in my 02 Z06 overhauled with new synchros and a steel shift fork from Kirkland Transmission. It's been intermittantly catching (feel resistance but with more force it will shift) when trying to shift out of 2nd and 4th.
Today it started mildly grinding on the 3-4 shift.
When they overhauled it they filled it with thier high-perf blend of oils which consisted of:
1 pint Redline GL5 gear Lube
1 pint Redline MTL synthetic
3 quarts Mobile 1 synthetic ATF
About 2 weeks ago I changed out to Valvoline Dexron III thinking the "catching" out of 2nd and 4th might be due to the strange oil blend, but I didn't notice any difference and today the grinding started.
I know I'm going to have to take it back for them to fix it but would like to be armed with as much info as possible when I do. Thanks for any help.
Today it started mildly grinding on the 3-4 shift.
When they overhauled it they filled it with thier high-perf blend of oils which consisted of:
1 pint Redline GL5 gear Lube
1 pint Redline MTL synthetic
3 quarts Mobile 1 synthetic ATF
About 2 weeks ago I changed out to Valvoline Dexron III thinking the "catching" out of 2nd and 4th might be due to the strange oil blend, but I didn't notice any difference and today the grinding started.
I know I'm going to have to take it back for them to fix it but would like to be armed with as much info as possible when I do. Thanks for any help.
Racer
Joined: Dec 2006
Posts: 4,434
Likes: 18
From: Braselton GA
Typically grinding is caused from a worn/weak blocking ring. These are the actual "friction elements" of the synchro. They have a friction surface which speeds up/slows down the gear to synch the speed, by engaging the "cone" area. If they are worn out, or don't have the proper friction element/fluid, they won't work right, and you'll get grinding on shifts.
Very odd yours would be doing this so soon. Did they replace the blocking rings? (You could replace the synchro's and not replace the rings, although I can't imagine somebody doing that).
Keep us posted
Very odd yours would be doing this so soon. Did they replace the blocking rings? (You could replace the synchro's and not replace the rings, although I can't imagine somebody doing that).
Keep us posted
Thread Starter
Melting Slicks
Joined: Dec 2006
Posts: 2,186
Likes: 2
From: Woodinville WA
It turned out to be a broken 3-4 slider key. They invited me into the shop to show and explain to me what happened and showed me the broken cheap-stamped key. I can't believe those keys come standard in a performance tranny
they look like they belong on a tonka toy.
Kirkland Transmission is going to cover all the labor and I am buying billet slider key sets for the 1-2, 3-4 & 5-6 shifts. They even recommended I buy them myself and drop ship them to the shop so I don't get charged their 40% markup. Turns out they are an honest shop.
they look like they belong on a tonka toy. Kirkland Transmission is going to cover all the labor and I am buying billet slider key sets for the 1-2, 3-4 & 5-6 shifts. They even recommended I buy them myself and drop ship them to the shop so I don't get charged their 40% markup. Turns out they are an honest shop.
Thread Starter
Melting Slicks
Joined: Dec 2006
Posts: 2,186
Likes: 2
From: Woodinville WA
Tranny Fixed
Got the car back yesterday, and drove it some more today, everything works as it should. I'm currently shifting mellow until my Kirban shifter gets delivered. My tranny guy wants me to get an aftermarket shifter with shift stops. The Kirban seems to be the shifter most highly acclaimed by professional tuners and racers.
Here is a pic of a broken synchro key next to a complete one. Notice the hollow stamped steel construction. These were replaced by solid billet steel keys.
Here is a pic of a broken synchro key next to a complete one. Notice the hollow stamped steel construction. These were replaced by solid billet steel keys.
Safety Car
Joined: Sep 2002
Posts: 4,030
Likes: 6
From: Maryland
Got the car back yesterday, and drove it some more today, everything works as it should. I'm currently shifting mellow until my Kirban shifter gets delivered. My tranny guy wants me to get an aftermarket shifter with shift stops. The Kirban seems to be the shifter most highly acclaimed by professional tuners and racers.
Here is a pic of a broken synchro key next to a complete one. Notice the hollow stamped steel construction. These were replaced by solid billet steel keys.
Here is a pic of a broken synchro key next to a complete one. Notice the hollow stamped steel construction. These were replaced by solid billet steel keys.
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