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Lost 5th and reverse at the same time?

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Old 08-07-18, 12:56 AM
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Lost 5th and reverse at the same time?

A little back ground on this situation is that my 5th gear has grinded since I got the car unless i revved the engine and shifted a weird way. I also knew it would eventually go but what i didn't expect was for my reverse to also get knocked out by it. My main question from here is why would reverse go also and should I get a new transmission from a reputable place or should i try to get the synchros replaced. I saw trans going for around 1k to 1.3k but I havent priced out replacing the synchros and from a few similar but not exact posts it would seem like synchros are a good cheaper choice but I am not sure that would fix the problem.
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Old 08-07-18, 02:38 AM
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I had this happen as well.

I had the 5th grind since I purchased the car. When racing I miss shifted 2nd to 5th which broke the 5th synchro in half and it got between the gears and pushed the counter gear into the side of the transmission case and punched a trans case dowel right out of the trans creating a leak.

Our transmission is an old 4+1 design which is basically a 4 speed with 5th gear added into the reverse casing. Broken bits floating around in that case can take out 5th and or reverse functions.

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Old 08-07-18, 03:53 AM
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I assume from your screen name we're talking about an FD. A weak 5th gear synchro was an issue on the early models that was corrected later with a strengthened synchro as well as a shift-select spindle that had a higher spring rate to reduce the chances of missing 3rd and getting 5th. That grind was a warning. It could have been dealt with relatively cheaply. Since now there's likely a lot of metal floating around inside, a thorough rebuild or replacement is in order. Rebuild rates will vary by region. I had a comprehensive rebuild done on mine a few years ago with all new bearings and synchros for about $1200 ( with me R & R'ing transmission). If you opt for a replacement transmission, used NADM transmissions come up occasionally in the Parts for Sale section. But I strongly recommend only dealing with long-time members with a good trader scores. Unless
you get lucky, shipping is going to be pricey IF they're willing to ship in the first place. JDM versions are also found on the net and ebay, but there you're REALLY buying an unknown. And at any rate the 5th gear is shorter which isn't as desirable IMO.
Given track-history this is probably never going to happen, but other preventative things to consider while the transmission is out...
*Replacement clutch fork
*Pilot bearing and seal
*Rear transmission seal
*Clutch/PP
*Resurface flywheel
*Re-torque engine tension bolts.
*Rear main seal.

Last edited by Sgtblue; 08-07-18 at 03:57 AM.
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Old 08-10-18, 03:50 AM
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Thanks for the replies, I think I`ll bring the car to my local trans shop and see what they quote me for a rebuild vs buying a new one. Btw it is an FD rx7 and Im building it for 450 whp in the coming months, with that in mind is it a good idea to stay with a stock transmission?
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Old 08-10-18, 04:05 AM
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Depends on if you drive like a high school knot-head and do high rpm clutch drops. Otherwise yes. But first things first....get a good running, sorted car...with a working transmission. Then worry about numbers to tell your friends.
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Old 08-14-18, 10:48 AM
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Ha well of course when i wanna go to take the car out to get fixed something else happens, its now stuck in I assume reverse gear because that where it wants to go when I let out the clutch. Im going to drop the trans in the next few days but was wondering if anyone could direct me to a good thread or video on pulling the trans out of my 1993 fd rx7. Also probably gonna have to swap in a jdm imported trans cause thats the only ones available. Will it match up without having to change anything?
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Old 08-14-18, 11:29 AM
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Nothing particularly difficult to pulling it. I think it’s also covered in the factory service manual which is available in a free download from the FAQ sticky. The only thing that’s sometimes tricky for a first-timer is dis-connecting the pull-type clutch. A how-to video is in those same stickies.

*Remove shift **** and interior shifter panel
*Remove shifter...I also CAREFULLY siphon gear oil out of reservoir.
*Unbolt clutch slave and set aside...don’t disconnect the line.
*Disconnect battery, disconnect and Remove Starter
*Remove exhaust aft of down-pipe
*Disconnect transmission harness
*Drop Power plant frame
*Index mark and unbolt U-joint from diff and pull driveshaft.
*Unbolt bellhousing and lower transmission. It may leak gear oil from the tail housing if you tip it.


JDM should bolt up the same but there may be a difference on the speedometer due to kph vs. mph. You’ll have to search and check. You’ll also need a pilot shaft alignment tool to reinstall a transmission.

Last edited by Sgtblue; 08-14-18 at 11:41 AM.
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Old 08-14-18, 01:20 PM
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Originally Posted by Sgtblue View Post
Nothing particularly difficult to pulling it. I think itís also covered in the factory service manual which is available in a free download from the FAQ sticky. The only thing thatís sometimes tricky for a first-timer is dis-connecting the pull-type clutch. A how-to video is in those same stickies.

*Remove shift **** and interior shifter panel
*Remove shifter...I also CAREFULLY siphon gear oil out of reservoir.
*Unbolt clutch slave and set aside...donít disconnect the line.
*Disconnect battery, disconnect and Remove Starter
*Remove exhaust aft of down-pipe
*Disconnect transmission harness
*Drop Power plant frame
*Index mark and unbolt U-joint from diff and pull driveshaft.
*Unbolt bellhousing and lower transmission. It may leak gear oil from the tail housing if you tip it.


JDM should bolt up the same but there may be a difference on the speedometer due to kph vs. mph. Youíll have to search and check. Youíll also need a pilot shaft alignment tool to reinstall a transmission.
Thanks for the reply ill look into the service manual and see if i can make sense of it.
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Old 08-14-18, 01:37 PM
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RE: the pull-type clutch....
If you remember from your little-kid days on how a Chinese Finger Trap works, it's the same principle for disconnecting the clutch. Watch the video and know that it can all be done thru the inspection hole with a large (long shaft) bladed screw-driver while pulling on the clutch fork. Most everyone struggles with it the first time. Last time I did it took < a minute.
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Old 08-18-18, 03:21 AM
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My 5th has also been grinding. So far ive been shifting it at 2k rpm with no grind. Probably will bring it to my local tranny shop when I work on the clutch. Ive been quoted $300 for just the 5th gear synchro and 1300 at another shop both without warranty unless they rebuild the whole thing.
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Old 08-18-18, 09:20 AM
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From the Sticky at the top of this section.....

THIS IS NOT MY WRITE UP. I simply saved this for other people so DON'T contact me about the tools

https://www.rx7club.com/3rd-generati...9/#post1284686


OP....If you R & R the transmission yourself it's probably best to pull the switches off the transmission and keep them before taking it into the shop. IIRC there are three. That's what I did. BUT, a word of caution. The reverse switch (turns on backup lights) and the neutral switch are really similar in appearance with just a little difference in the short pig-tail harness. Be sure to mark them because if you reinstall them wrong you have to drop the tranny a second time. Ask me how I know.

Last edited by Sgtblue; 08-18-18 at 09:29 AM.
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Old 08-19-18, 05:35 PM
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Originally Posted by Sgtblue View Post
From the Sticky at the top of this section.....

THIS IS NOT MY WRITE UP. I simply saved this for other people so DON'T contact me about the tools

https://www.rx7club.com/3rd-generati...9/#post1284686


OP....If you R & R the transmission yourself it's probably best to pull the switches off the transmission and keep them before taking it into the shop. IIRC there are three. That's what I did. BUT, a word of caution. The reverse switch (turns on backup lights) and the neutral switch are really similar in appearance with just a little difference in the short pig-tail harness. Be sure to mark them because if you reinstall them wrong you have to drop the tranny a second time. Ask me how I know.
ha thanks for the advice
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