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My shifter started popping out of 5th gear.

Its happened to others and theres plenty of searchable material as to why this happens(wear caused by constant pressure on the shifter.... like a hand). The usual remedy is simple....find another transmission from the junkyard to source a suitable 5th gear gearset.

Since the 5th gear is readily accessible through the 5th gear cover, you dont need to pull the entire transmission to get whats needed. You do need a breaker bar a 36mm socket a 26mm socket and a roll pin punch to remover the main gearshaft nuts and roll pin for the 5th gear selector fork.

But how do you recognize a suitable replacement :confused: I hadnt read a description of what to look for nor seen pictures of the issue at hand.


Since I had a spare transmission to work with I took a look at the 5th gear clusters to see what the issue was......

The area you need to look for is the teeth on the clutch hub and the teeth that they will mate with on the primary 5th gear.


See how the teeth have been flattened on their left side?


Heres a shot of the same teeth on the replacement gearset. Note that they are in much better condition.



Here is a side by side shot of the teeth of the 5th gear clutch hub. these teeth would be facing "down" (in towards the transmission) whereas the teeth on the primary 5th gear would be facing "up" (towards the 5th gear cover).

You can see the worn teeth on the left clutch hub and how much gap has been created in the assembly.


Pretty worn, beat up and generally unhappy teeth in the clutch assembly


In this shot the clutch hub teeth still have a well defined profile.


Ill take a guess and say that the teeth of the primary 5th gear are built with a bit of reverse taper to be able to have a good mechanical friction with the teeth of the clutch hub. Once the taper gets worn out theres little to have them interlock together and the shifter then pops out of gear.

So thats it then. If you are having issue with 5th gear...this is the issue and this is how you recognize a worn 5th gear from not worn.

Gavin
 

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Nice find :tup:

it seems that people leaning on the gear lever is a fairly common problem. My father always told me not to do it at all when he was teaching me how to drive.

He explained to me that one of the cars he had owned, the third gear fork was worn down from people pushing the gear lever forward while in 3rd.

so get your hand off it people!
 

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I have NEVER leaned on the gearshift, not for 20 years. Still yesterday 5th gear started popping out of gear. Scared me a lot the first time, running 70mph on cruise control. Now I'm wondering do I need the 5th gearset, a shift fork, the clutch hub sleeve, what all exactly?
 

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thats wild. I've never leaned on the shifter. I lean on the arm rest ....o use both hands lol.
 

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I dont doubt you both saying that you have never used the shifter as an armrest. I dont either, its just how I was taught....."both hands on the wheel at 9 and 3 position(or alternately 10 and 2)"

We used to joke that there was an even more common driving position....hands at "12 and 5" (that is...left hand at 12-o-clock on the wheel, right hand on the 5-speed). Im sure youve see this driving style more often than not. ;)

mlp-mx6....As for your gears...possibly. Or it could be as one of the aussies recently discovered when 5th gear wasnt holding....the transmission was out of lubricant 0.o

Gavin
 

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Yeah, I'm old enough for 10 and 2.

But I love my Mazda. I've loved her for 20 years next month.
 

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Another thing I've ran into are the teeth on the gear rounding the tips off, takes a lot of wear for it to pop out of gear this way, but another way.

I have 9 GT trannies torn apart across the back wall of my garage, happens to be my only experience inside of them, but all were marked for symptoms before being stored...so when I found problems, I looked at the case for what it's issue was...and no I didn't break them all;) only 2 of them were mine.

Most were 5th gear or 3rd gear popping, and most of them were actually forks worn, I assumed it was from people trying to hold it in gear when they started popping out, never thought of it as resting on the shifter.
 

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Really wish I could see these pics. I have a h trans that pops out of fifth when you floor it. I have it apart now I was hoping to see some obvious fork wear but nothing that raises much alarm. I attached some pics if anyone is out there, I will take the cluster all apart tomorrow and see what I find.
 

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You need to take a picture with the 5th not engaged. 5th wears the syncro teeth, but I can't see because they are covered. I don't think that it is your shift fork. I replaced my 5th gear and the syncro hub assembly a couple of years ago because it would pop out of fifth, mainly under power.
 
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You need to take a picture with the 5th not engaged. 5th wears the syncro teeth, but I can't see because they are covered. I don't think that it is your shift fork. I replaced my 5th gear and the syncro hub assembly a couple of years ago because it would pop out of fifth, mainly under power.
 

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Your 5th/reverse fork has some wear sings on the bottom side.
-Reinstall the fork and move the shifter lever (where the two green bushings go) to shift into 5th gear.
The transmission is in reverse in the upper picture.
Make sure that by using the shift lever (turn right and pull back) that 5th gear is fully engaged. If not than the wear on the 5th gear fork and on the 5th gear shift box (sits lower on the rod and gets moved by the shift gate) and the shift lever travel/shift gate ball aren't enough to fully engage 5th gear completely and the transmission pops out.
If the shift lever fully engages 5th gear than look at the 5th gear shift rod bearings. There is one held in the side of the transmission with an m14 headed m8 bolt and a spring and the three that bolt up at the top of the 5th gear rod, two large cylinder bearings and one small one that sits inside the center rod.

If the shift boxes are rounded out you can fill them in with weld and file them back to square. These boxes are always rounded by the shift gate ball, this is caused by play in the shifer assembly -bushings and bolts and keeping one hand on the shift knob. And probably bad gear oil flow to 5th gear components through the gear shaft and added friction on the aluminum 5th/reverse fork.
If everything seems okay and you think its the syncros, flip the syncro assembly for 5th and reverse and don't floor the car in reverse.

While you have the transmission apart I highly recommend taking the gear assemblies out, take a spray bottle and varsol, both rods have holes in the center that gear oil passes through and comes out at all the gears and syncros, spray varsol in the center shaft and between all the gears and move the syncros around while doing it, spin the gears in neutral and spray varsol in them... use compressed air to blast of the varsol ... eventually you will notice the varsol flows better and pours out at every gear and syncro, you will also notice the gears and syncros will start to wiggle a bit on the gear assembly, as though you have loosened them all up with the varsol, don't panic that's the way they're supposed to be, gear oil will flow better and the gears will shift easier.

There are 3 seal/gaskets in the transmission. you should change two of them while the transmission is apart, both are like small axle seals, on is in the bell housing (main seal on the shaft that goes in the clutch) the other is on the shifter lever.

You should weld the differential shaft to the differential housing, right now it is held in place by the same little roll pin that the 5th reverse fork was held with, if it shears off the differential shaft shouts out of the transmission housing, ruins the differential, the diff gears, the transmission housing and can take teeth off the gears if debris gets to them. When the diff shaft goes through the transmission housing it's only good to salvageable parts from if they survive and can't/ cannot be rebuilt. Okay maybe it can but it would probably be cheaper to buy a jetrag 6speed fwd 600flb torque aftermarket transmission, get taller 1,2,3 gears than factory 4 and 5 th should stay the same and add 6th to that, for fuel economy on the highway (cough, bullshit, cough cough) i mean to reach 200mph.

If you are screwed I should have some aluminum 5th / reverse forks without wear in my spare transmission parts and good bearing balls /cylinders and springs.

And if you are wondering where I got bins of spare f2t transmission parts. Just weld the differential shaft.
 
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If your having trouble finding shift rod bushings mazda proteges use the same green bushings.
 

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Upon further inspection...a lot of heat and the selector ring is worn
 

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That I have used replacements for, also you interested in that differential housing gear on ebay for 3.51$, it's brand new and when they could be purchased where 50-60+$ each.
Or I will trade you a working 5th gear synchros assembly for a 3.51$ Diff gear you can buy on Ebay. You buy the gear and I pay shipping from you to me, I give you the synchro assembly and you pay shipping from me to you.
That would be a Synchros assembly for 3.51$ + shipping.
 

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Really wish I could see these pics. I have a h trans that pops out of fifth when you floor it. I have it apart now I was hoping to see some obvious fork wear but nothing that raises much alarm. I attached some pics if anyone is out there, I will take the cluster all apart tomorrow and see what I find.
Good quality cool pics; thanks~!
 

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I have NEVER leaned on the gearshift, not for 20 years. Still yesterday 5th gear started popping out of gear. Scared me a lot the first time, running 70mph on cruise control. Now I'm wondering do I need the 5th gearset, a shift fork, the clutch hub sleeve, what all exactly?
Just need a new gear set the clutch hub is reversible as it is symmetrical and new lock nuts
 
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