Quick grind into 5th, only at high RPM's???
#1
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Quick grind into 5th, only at high RPM's???
My car is a '98 Z28 M6, new GM slave and master, and new LS7 clutch. The car shifts great at any gear without any grinding or anything, except...
A little bit ago I was out cruising on the freeway and there was nobody around, so I had a quick run. During the 4-5 shift it had a really quick grind as it went into gear. It stayed in gear and didn't pop out or continue to grind or anything abnormal. I slowed down some and sped back up again, and once again it happened as I quickly shifted into 5th at high RPM's.
So, I tried it a 3rd time, but this time as I got close to redline in 4th and prepared to shift, I took it easy and shifted slower and more casually into 5th, and it didn't grind. It never grinds 5th (or any gear) when driving normal. It downshifts from 6th to 5th easily without a problem.
I'm assuming this is a syncro issue, but I've done a lot of research on here and 5th doesn't really seem like a common problem. Am I on the right track, or is there something I am missing? Will the grinding eventually get worse?
A little bit ago I was out cruising on the freeway and there was nobody around, so I had a quick run. During the 4-5 shift it had a really quick grind as it went into gear. It stayed in gear and didn't pop out or continue to grind or anything abnormal. I slowed down some and sped back up again, and once again it happened as I quickly shifted into 5th at high RPM's.
So, I tried it a 3rd time, but this time as I got close to redline in 4th and prepared to shift, I took it easy and shifted slower and more casually into 5th, and it didn't grind. It never grinds 5th (or any gear) when driving normal. It downshifts from 6th to 5th easily without a problem.
I'm assuming this is a syncro issue, but I've done a lot of research on here and 5th doesn't really seem like a common problem. Am I on the right track, or is there something I am missing? Will the grinding eventually get worse?
#2
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What is your current mileage? I have seen more plastic fork pads broken causing too much play and not engaging the syncro all the way in. This is 1-2 shift fork but you get the idea.....
What's left of the fork pads......
What's left of the fork pads......
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Yeah, it was the first time I did it and I don't plan on doing it again. I was just wondering if it was a common problem? Hopefully not a sign of things to come. I don't want it to get worse and start doing it every time I try 5th
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It will if your fork pads are already ruined, which it sounds like they might be. I agree tho, why do you need to powershift 5th? Are you running some crazy gear? You hit 5th at what 120mph?
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Mine does this also, but not all the time. Also this past weekend I took a trip out of town and when I downshifted into 5th from 6th it would grind going into gear. If I down shifted to 4th then 5th it would go in no problem.
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i just bought a car with a "stage 3" tranny. it grinded into 5th very slightly. after a while, i has become so bad towhere if i try to shift into 5th, it will grind so bad you can feel the tranny moving. i go from 4th to 6th but the tranny will sometimes not let me leave 6th. i don't want to seem pesimistic, but i would take care of that syncro
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The car still shifts perfectly, whether it's daily driving or racing. This was the first time I've encountered a problem, and I don't see it being a problem in the future seeing as how it's avoidable and unnecessary. I really don't think it's anything to worry about as long as it doesn't get worse. If it starts to grind during everyday driving, that's when I'll start to worry.
Stock gear. It wasn't a powershift, but more of a "speed shift". I shifted quickly, but I let off the gas when I shifted. There really isn't a need to do it in 5th, I just hadn't done it before on the 4-5 shift and I was surprised at what happened when I tried it. Yeah it was somewhere around 115mph IIRC.
Stock gear. It wasn't a powershift, but more of a "speed shift". I shifted quickly, but I let off the gas when I shifted. There really isn't a need to do it in 5th, I just hadn't done it before on the 4-5 shift and I was surprised at what happened when I tried it. Yeah it was somewhere around 115mph IIRC.