Muncie 4 speed rebuild
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Muncie 4 speed rebuild
Anyone know of a reputable place I can ship my m21 Muncie off my 69 for a rebuild. Unfortunately I have not found anyone local that I trust. I am thinking I will remove it myself and ship it somewhere for a rebuild. I am in Beaumont TX which is 90 miles east of Houston.
Reason for rebuild is it slips out of gear on deceleration and I hear a whine in second gear. Everything I have was tells me it sounds like synchronizes are worn.
Reason for rebuild is it slips out of gear on deceleration and I hear a whine in second gear. Everything I have was tells me it sounds like synchronizes are worn.
Last edited by Bhebert449; Mar 30, 2019 at 11:02 AM.
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Is my vette stock?? HAHA
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If it pops out of second on decel its usually the synchro slider not holding anymore. Paul at 5speeds is your best bet. You can look up his how to videos on youtube. I rebuilt mine with his videos and how to books. Its really easy. His vids are the best. I bought my parts from him ( http://www.5speeds.com/cart/index.ph...5_17_69&page=3 ) and from the gearbox http://www.thegearbox.org/Muncie.html
They make some really good speed parts for muncies now that make them even easier to rebuild like caged bearings and bolt in cluster pins and grooved bearing sleeves. You can even buy everything to upgrade your M20/21 to a M22 or just buy them rebuilt for $2000. I rebuilt mine with all new everything except the main shaft for about $1000
They make some really good speed parts for muncies now that make them even easier to rebuild like caged bearings and bolt in cluster pins and grooved bearing sleeves. You can even buy everything to upgrade your M20/21 to a M22 or just buy them rebuilt for $2000. I rebuilt mine with all new everything except the main shaft for about $1000
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From: Syracuse NY
Before you go chasing synchros and start gutting your transmission, check the cover. The 'door' that the shift linkage goes thru. The legs on the inside get worn and will make you pop out of gear on decel.
I had my transmission out twice over a 4 month period, diagnosing the same problem. Every time Id let off the gas, the shifter would just pop into neutral. I replaced synchros, gears and the main shaft. After the 2nd rebuild I took the car to a guy who knew old Muncies (took me a while to find somebody) and he immediately replaced the cover. Problem solved, lots of money wasted, but I learned how to tear apart and rebuild a Muncie.
I had my transmission out twice over a 4 month period, diagnosing the same problem. Every time Id let off the gas, the shifter would just pop into neutral. I replaced synchros, gears and the main shaft. After the 2nd rebuild I took the car to a guy who knew old Muncies (took me a while to find somebody) and he immediately replaced the cover. Problem solved, lots of money wasted, but I learned how to tear apart and rebuild a Muncie.
