Track whores with MRs?
#106
Just because you don't use 4th doesn't mean it won't heat up. Everything is spinning even if you aren't in that actual gear. Which is why if you drive the car after losing a gear, even if you don't use the gear you lost, you still have potential to create more damage.
#108
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So what kinds of failures are people seeing? Warr blasted 4th gear, and there have been reports of other failures, but what exactly is failing? Is it the gear teeth, the dog teeth, the shaft splines, the synchro, the selector fork, input shaft, output shaft... Is there any relation to the faulures?
#115
Originally Posted by Wheelhaus
That sounds like it's caused by shock load.. And if it's overheating, those teeth would be one of the first things to endure the thermal breakdown of the trans lube.
#117
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Join Date: Apr 2006
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Originally Posted by Warrtalon
YOu don't autocross in 4th, so it's no worry. I have done 200+ drag runs, 20+ autocrosses, and 500 miles of track time before 4th went out. I also drive really hard and am pretty fast, so it wasn't a big surprise this happened to me.
i am honestly surprised this didn't happen sooner Clay. With all your launches and track days (road/auto/drag) this should have happened long ago.
#118
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I kind of found this thread pretty late into it, but for what it's worth here's another case to consider. I damaged my 4th gear sleeve and fork on the 2nd track event - the sleeve got so hot it was blue in places, because it was no longer "round" shifting became rather difficult, but there was no gear/teeth damage. Here's a comparison of the damaged one vs. the replacement. It's possible that this was partially driver error (e.g.resting the hand on the shifter for too long).
The shop where it was fixed also commented on how small (fragile) the 6sp gears are compared to the 5sp (they do a lot of rally evo's there). I was on stock fluid at the time. I have since experimented with a lot of different fluids, because in the generally cooler climate of Seattle, the stock fluid shifts like ***. The best I have found is GM synchromesh (not BG synchroshift). The BG stuff does break down under high heat - after an auto-x on a hot day the BG fluid had lost a lot of its smoothness. The GM stuff has held up to all day track abuse without loss in feel. I do change fluid after each event though. The GM part number for the stuff is 12345349, it states on the container that it is specifically high heat tolerant.
The shop where it was fixed also commented on how small (fragile) the 6sp gears are compared to the 5sp (they do a lot of rally evo's there). I was on stock fluid at the time. I have since experimented with a lot of different fluids, because in the generally cooler climate of Seattle, the stock fluid shifts like ***. The best I have found is GM synchromesh (not BG synchroshift). The BG stuff does break down under high heat - after an auto-x on a hot day the BG fluid had lost a lot of its smoothness. The GM stuff has held up to all day track abuse without loss in feel. I do change fluid after each event though. The GM part number for the stuff is 12345349, it states on the container that it is specifically high heat tolerant.
#120
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Originally Posted by Wheelhaus
^ that's really interesting... What exactly is worn in the picture besides the fork?