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| | | | Joined: Mar 2007 Posts: 24 Wrench Fetcher | | Wrench Fetcher Joined: Mar 2007 Posts: 24 | Tried a search but found nothing. My 1957 1/2 ton with 3 on the column consistently pops out of 3rd gear. What needs to be done to fix this and where can I find the parts (if they are necessary)? thanks
Two 1957 Chevy Step Sides
1988 Fiero Formula
1987 Fiero GT
1984 Fiero Indy
... yes I like Fieros also..
;-)
| | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | worn synchro - pretty common, but don't know the parts source
Bill | | | | | Joined: May 2006 Posts: 8,351 'Bolter | | 'Bolter Joined: May 2006 Posts: 8,351 | Might try these guys, the specialize in older GM manuals, mainly 'Vettes, but he does 3 speeds, too. http://www.pipersauto.com/4speeds.html
Bill Burmeister
| | | | | Joined: Apr 2005 Posts: 82 Wrench Fetcher | | Wrench Fetcher Joined: Apr 2005 Posts: 82 | I might add that there are other reasons that might cause this problem. If you have had the transmission out for any reason, it might be misaligned or even loose. You may want to check your shop manual as it should give a list of remedies for this problem.
Richard
58 3104
| | | | | Joined: Jul 2004 Posts: 5,708 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 5,708 | DadsApache,
A worn clutch gear (input shaft) gave me the same problem once. After replacing almost everything, I took the truck to my cousins transmission shop...they stuck a new clutch gear in it and the problem was solved.
Stuart | | | | | Joined: Mar 2008 Posts: 55 Shop Shark | | Shop Shark Joined: Mar 2008 Posts: 55 | That trans mission is the same all the way up to 1967 car and truck. the only changes were tail housing lengths and trucks have two threaded holes for bottom bellhousing bolts. you can take the brass ring from the second gear side of the syncro and swap with third. when you take it apart there are 14 large and 24 small needle bearings you will have to use chassis grease and put back in. OldWolf | | | | | Joined: Apr 2005 Posts: 2,102 'Bolter | | 'Bolter Joined: Apr 2005 Posts: 2,102 | The common problem is the syncro but as mentioned above a 50 year old vehicle can have other worn parts. You can get a rebuilt 2-3 syncro assy from Anaheim Gear in Anaheim, CA. for $125.
Fred
1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine
| | | | | Joined: Feb 2004 Posts: 29,869 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,869 | No, guys, the synchro blocker ring won't cause one to pop out of gear. The collar that engages the input gear, and the gear itself are worn, and will have to be replaced. A synchronizer assembly consists of the hub, the outer collar, and the blocker rings, and it should be replaced as a unit if possible. The notched teeth on the back of the input shaft, and the synchronizer collar mesh to transmit power in high gear, and one or both of them with chips or wear is the cause of the transmission jumping out of gear.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
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| | | | | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | Also check the detentes in the cover. If the springs are weak or broken or the grooves are worn it can cause or aggravate the problem. If the brgs or thrust washers are worn it can cause a condition like Jerry says.
They say money can't buy happiness. It can buy old Chevy trucks though. Same thing. 1972 Chevy c10 Cheyenne SuperIn the Gallery Forum | | | | | Joined: Apr 2005 Posts: 641 Shop Shark | | Shop Shark Joined: Apr 2005 Posts: 641 | time to put in a 4 speed muncie and cut a hole in the floor | | | | | Joined: Mar 2007 Posts: 24 Wrench Fetcher | | Wrench Fetcher Joined: Mar 2007 Posts: 24 | What 4 speed Muncie are you referring to? I'm game to replace the 3-speed with a 4 or 5 speed
Two 1957 Chevy Step Sides
1988 Fiero Formula
1987 Fiero GT
1984 Fiero Indy
... yes I like Fieros also..
;-)
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