5 speed carnage
#1
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5 speed carnage
So I took apart my busted 5 speed:
Here are the guts:
Where'd 3rd gear go?
Here it is!
What sucks is the syncros in this transmission are in perfect shape and it used to shift perfectly. The new (to me) one doesn't shift quite as nicely.
This is kinda cool:
It's kind of a trough that collects oil and feeds the driveshaft bearing here:
Damnit I need a 6 speed.
Here are the guts:
Where'd 3rd gear go?
Here it is!
What sucks is the syncros in this transmission are in perfect shape and it used to shift perfectly. The new (to me) one doesn't shift quite as nicely.
This is kinda cool:
It's kind of a trough that collects oil and feeds the driveshaft bearing here:
Damnit I need a 6 speed.
#4
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Did it free-rev in 3rd? My tranny acted the same in 3rd as it did in neutral after I toasted it - I could put it in 3rd, let the clutch out, and get out of the car, and it wouldn't go anywhere.
#6
I'm betting my 3rd gear is going to look like that soon.
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#7
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It is possible to swap gears, and replace broken ones. But unless it's a qualfie set, it's just going to break again. It looks like Mazda used a pretty steep helix angle to get rid of noise, if I'm not mistaken that's part of the reason the gears aren't terribly strong. That amd material I'm guessing.
#10
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The main gear is always engaged on both the main shaft and the countershaft. The division between the input and output halves of the main shaft is just after (above) the main gear. All countergears are continuously engaged on the countershaft.
The main gear drives the countershaft, and the four countergears continuously drive their mating gears on the main shaft. To select 1, 2, 3, or 5, the appropriate output gear is locked to the main output shaft, with the other output gears freewheeling.
There is no 4'th gear per se. As 4'th is 1:1, to achieve that ratio, the input shaft and the output shaft are simply locked together, and the countershaft freewheels all of the main gears.
Reverse is similar, but with one additional gear in the lineup- the reverse countergear drives an idler gear, and then the idler gear drives the reverse main output gear.
#11
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I've said before, 3k for a transmission gear set from qualfie is very reasonable. Keep in mind a ring/pinion set is not terribly precise aside from a ground bore. Theyre a meshed set, meaning the more you run it, the more the pinion grinds into the ring. You can see from Joe perez's recent write up about his new gear set that the lathe grooves are still visible. Look up the price for a ring pinion gear set from a reputable gear company like qualfie, and times it by the six (I think reverse is included) gears you get with a transmission set, and add in the money to make the gears somewere near a quality class 12, and you should be somewhere near their price. Kudos to whoever prooves me wrong and makes a cheaper set, but I'd be incredibly surpised if it were possible.
#12
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Yes it is, and until I get a 6 speed I'm keeping this gearset as a spare. Hopefully I blow up 2nd gear next time.
Joe, you're badass. I was wondering where 4th gear was.
#14
Additional information:
HowStuffWorks "How Manual Transmissions Work"
There is a manual transmission simulator in that article that lets you switch gears and watch what happens in the transmission.
HowStuffWorks "How Manual Transmissions Work"
There is a manual transmission simulator in that article that lets you switch gears and watch what happens in the transmission.