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Old 08-14-2014, 01:18 PM   #1
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Default Lost 5th gear, then I didn't. What do?

Over the last few days, 5th gear had been a bit notchy while driving, and yesterday I lost it entirely. All other gears including reverse were fine. Today, I double clutched and managed to wiggle the shifter into 5th, and now everything is fine. I can shift to 5th consistently with no notchyness.

Mechanically, what the hell happened? I'm not very familiar with the inner workings of a trans, so I can't visualize what was happening. Is this problem indicative of an impending failure?
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Old 08-14-2014, 01:28 PM   #2
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its cause you were granny shifting not double clutching like you were supposed to



I'm guessing if it works fine, it was a synchro that got out of whack, or your shift fork got stuck
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Old 08-14-2014, 05:50 PM   #3
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Originally Posted by dieselmiata View Post
Over the last few days, 5th gear had been a bit notchy while driving, and yesterday I lost it entirely. All other gears including reverse were fine. Today, I double clutched and managed to wiggle the shifter into 5th, and now everything is fine. I can shift to 5th consistently with no notchyness.

Mechanically, what the hell happened? I'm not very familiar with the inner workings of a trans, so I can't visualize what was happening. Is this problem indicative of an impending failure?

5 or 6 speed transmission? They are very different.

We broke the 5-R shifter fork on a 6 speed once. One side of the fork broke off leaving 1/2 the fork only. shifting fast caused the remaining what was left of the fork to jump out of the groove and not move the 5-R synchro hub.

Shifting very very slowly, it would stay in the groove and engage the next gear...

The risk is that you end up engaging 2 gears at once, 5th that doesn't disengage on a down shift to 4th that DOES engage. Both being engaged with different ratios causes the output shaft to stop turning likely locked up rear tires, followed shortly with lots of bent and broken drive line parts and possibly a trip into the wall.

Lots of info available on high HP transmissions breaking... see links on transmission woes and another 6 speed bites the dust and lots of others...
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Old 08-14-2014, 05:59 PM   #4
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And just a minute ago I was making fun of someone for being vague.

It's a 5-speed, 170K miles on it, no issues until the gear getting stuck. I have had some deceleration rattle since installing a FM clutch a few months back, but as I understand it it's not abnormal after a clutch job.

Is there a way I can inspect the shift fork without dropping the transmission entirely?
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Old 08-16-2014, 03:01 PM   #5
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Is there a way I can inspect the shift fork without dropping the transmission entirely?
Not likely, unless you are gifted with xray vision, as the shift fork is internal, it physically moves the gear/synchronizer assembly
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Old 08-16-2014, 03:47 PM   #6
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And just a minute ago I was making fun of someone for being vague.

It's a 5-speed, 170K miles on it, no issues until the gear getting stuck. I have had some deceleration rattle since installing a FM clutch a few months back, but as I understand it it's not abnormal after a clutch job.

Is there a way I can inspect the shift fork without dropping the transmission entirely?

Like anything mechanical, it can be repaired. Get a Mazda factory 5 speed repair manual, have a read and determine for your self if you want to tackle it.

Alternatively, If the transmission is really done, then just go buy a replacement 5 speed for $200-$500.

Or a 6 speed for a few $100's more.
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