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Transmission Grinds in 3rd gear

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Old 10-03-19, 05:55 PM
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Transmission Grinds in 3rd gear

I just picked up a 1995 Rx7 that grinds when shifting into third gear, unless you let the RPMs drop WAY down. The previous owner replaced the motor mounts and the shifter bushings. The shifter is also pretty stiff and when you let off the throttle abruptly from a 2nd gear pull it pops out of gear. Is there a cause for this other than the synchros? I am trying to rule out other possibilities before pulling the trans.

I should add that the car only has 63k miles on it. I have a hard time believing that the synchros are going out at such low millage, but I guess its possible.

Last edited by suzukisteve; 10-03-19 at 07:55 PM.
Old 10-03-19, 06:03 PM
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Old 10-07-19, 05:56 AM
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Pull the trans. It's time for a rebuild.
Old 10-07-19, 09:39 AM
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I took the car into a hobby shop and changed the transmission and rear diff oil. The transmission oil was pretty clean and there was not a lot of medal around the magnet. After talking to a mechanic at the shop he suggested that the clutch is going bad. I am thinking this would make sense as the clutch medal slightly sticks to the floor, is difficult to modulate and there is a slight bit of chatter starting out. I am probably going to replace it with a stage 1 or quality oem clutch. Any suggestions on brands and where to buy would be appreciated.
Old 10-07-19, 09:56 AM
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Not seeing the clutch contributing to it falling out of gear. Off-hand that can be caused by ALOT of driveline movement or it can be internal to the transmission. In any case the transmission needs to be removed. If you do need a clutch for a stock or mildly modified car I’d recommend the ACT Street/Strip...I think they call them “street performance” clutches now.
http://banzai-racing.com/store/93+_r...lutch_kit.html

At 65k + mileage there are a few other things that are recommended while the transmission is out. Most don’t cost much...pilot bearing and seal, rear transmission seal are inexpensive. Most kits come with the throw-out bearing but if not, I’d change that too.

Last edited by Sgtblue; 10-07-19 at 10:06 AM.
Old 10-07-19, 03:32 PM
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Originally Posted by Sgtblue
Not seeing the clutch contributing to it falling out of gear. Off-hand that can be caused by ALOT of driveline movement or it can be internal to the transmission. In any case the transmission needs to be removed. If you do need a clutch for a stock or mildly modified car I’d recommend the ACT Street/Strip...I think they call them “street performance” clutches now.
ACT HD Clutch Kit (93+RX-7)

At 65k + mileage there are a few other things that are recommended while the transmission is out. Most don’t cost much...pilot bearing and seal, rear transmission seal are inexpensive. Most kits come with the throw-out bearing but if not, I’d change that too.
I was planning on replacing those bearing and seals while the transmission was out. I was going to buy a Bonez clutch from rx7.com because they will let you rent a pilot bearing removal tool with the purchase, but after talking to another mechanic today I think the synchros are definitely going bad.

For now I plan on driving the car and taking it easy, then parking it for 6 months (work related). Then replacing the clutch and getting the transmission rebuilt when I have a bigger garage and get my second car back.
Old 10-11-19, 05:42 AM
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That sounds like a good plan. Glad you got a second opinion on it before you spent more money attempting to dance around the trans with other repairs.
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