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i searched.... 4th gear issue!!!

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Old Dec 13, 2010 | 10:20 PM
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Default i searched.... 4th gear issue!!!

So my car is stuck in 4th gear....kinda. Physically i can move the shifter wherever but its always in 4th gear including when it should be in neutral. It has never stuck the shifter in 4th. never any problems shifting. no noises. it just started yesterday after a 45 mile drive.
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Old Dec 14, 2010 | 07:55 AM
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You broke a Keyway (i think is the term).

Stop driving and get it fixed. REBUILD TIME!! You could get by with skipping but once it gets jammed in there, your fucked.
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Old Dec 14, 2010 | 08:04 AM
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Sense it moves into all gears and is still stuck in 4th you could have broken the 3/4 fork as well. Either way it will have to come apart. Let me know if there is anything we can do for you.
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Old Dec 14, 2010 | 08:38 AM
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Yep. 3/4 fork is likely busted.
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Old Dec 14, 2010 | 09:14 AM
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Pull the front cover, remove the keys and front spring and drive it. That way, if everyone did that, we wouldn't have this thread again and again.

just kidding.
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Old Dec 14, 2010 | 10:44 AM
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Originally Posted by wrd1972
Yep. 3/4 fork is likely busted.
That is 100% correct! That's just about the only way that it could be stuck in 4th with the shifter moving freely.
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Old Dec 14, 2010 | 12:06 PM
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If it was indeed stuck in 4th (broken fork) and you moved it into another gear, it would lock up the rotating assembly in the trans trying to force a direct AND geared rotation.

How can you tell it's stuck in 4th? What are the symptoms, just bogging down when you let out the clutch? It sounds more like the roll pin(s) or something in the shiftrail is astray.
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Old Dec 14, 2010 | 09:11 PM
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Originally Posted by 85MikeTPI
If it was indeed stuck in 4th (broken fork) and you moved it into another gear, it would lock up the rotating assembly in the trans trying to force a direct AND geared rotation.

How can you tell it's stuck in 4th? What are the symptoms, just bogging down when you let out the clutch? It sounds more like the roll pin(s) or something in the shiftrail is astray.
I'm with Mikey. If it were a true broken fork any other gear selection would stall the engine. I think its a damaged socket for the shifter or some other linkage issue( pin as above).
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Old Dec 14, 2010 | 10:42 PM
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Well for the guys asking. when i put it in any gear including neutral it will bog and die when i let out the clutch trying to move forward. curious i stalled the car up and rode the clutch to get it moving. 1500 rpm at 30mph with my 410 rear gears is what i normally see when i do that leading me to the 4th gear being stuck cause i drive it like that around town normally. that was the last time i drove it just to try and diagnose it. when i shift it into any gear its always in 4th and there is absolutely no grinding or anything.

had a shop today say something about the roll pin or that cup the bottom of the shifter sits in so tomorrow im gonna start with taking that apart. hope thats it...
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Old Dec 14, 2010 | 11:13 PM
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Originally Posted by spook99maro
Well for the guys asking. when i put it in any gear including neutral it will bog and die when i let out the clutch trying to move forward. curious i stalled the car up and rode the clutch to get it moving. 1500 rpm at 30mph with my 410 rear gears is what i normally see when i do that leading me to the 4th gear being stuck cause i drive it like that around town normally. that was the last time i drove it just to try and diagnose it. when i shift it into any gear its always in 4th and there is absolutely no grinding or anything.

had a shop today say something about the roll pin or that cup the bottom of the shifter sits in so tomorrow im gonna start with taking that apart. hope thats it...
That'll just end up being step 1 of disassembly while fixing it.

There's nothing wrong with pulling the front cover off first to inspect the 3/4 fork / synchro, although it's a little bit tricky to get it back on.
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Old Dec 15, 2010 | 01:17 AM
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It could also be a broken roll pin in the shift rail or the steel piece that holds the fork onto the rail is broken. Now that I think of it, I saw this exact same thing happen to a T45, and this piece was broken
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Old Dec 18, 2010 | 06:22 PM
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ok tranny is out of car.

today i drained it and less than half a quart came out . from there i proceeded to break down the tranny and almost everything looks perfect. its still in a few sub assemblies at the moment but all i have found so far is a broke 5/6 fork pad.

my last question here and im sure this is the problem. the input shaft wont come off the main shaft and the slit right about 4th gear before the engagement teeth/blocker ring had metal shavings there. is there a roller bearing or something right there between the shafts or something? i believe this is why 4th gear was always engaged as it is the only gear that doesnt spin freely although im not 100% its supposed to.

any techs willing to help / point me in the right direction i will greatly appreciate it.
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Old Dec 18, 2010 | 09:02 PM
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update. got the shafts seperated and that bearing was fubar'd. anyone know a supplier that would be willing to sell just that bearing so i dont have to buy a full bearing set when the rest of them checked out good?

ordering a rebuild kit, steel 3/4 shift fork, billet keys 1-4, bronze pads 1-4. any other thing i should look at by chance that i may have missed?
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Old Dec 19, 2010 | 09:47 AM
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The small bearing & race between mainshaft and input shaft can be picked up at most any autoparts store as a Timken SET12.
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Old Dec 19, 2010 | 01:01 PM
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thanks for that info i appreciate it
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Old Dec 20, 2010 | 11:11 AM
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Originally Posted by 85MikeTPI
The small bearing & race between mainshaft and input shaft can be picked up at most any autoparts store as a Timken SET12.
Or a LM12749 bearing & LM12711 race

Its used as a trailer wheel bearing lol
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Old Dec 20, 2010 | 01:59 PM
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all the parts stores here either have national, bca, or napa's bearings are these comparable to the timkens as far as reliability for a trans?
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Old Dec 20, 2010 | 03:23 PM
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Originally Posted by spook99maro
all the parts stores here either have national, bca, or napa's bearings are these comparable to the timkens as far as reliability for a trans?
Some of these re-brand Timken bearings. Ask if you can take one out of the package and see if it's stamped with timken on the inner and outer races.
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