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Hey guys- had an odd thing now happen twice over last month. I punch it in 2nd and when I go for 3rd gear it does not happen. The transmission is then stuck in 2nd. Driven home twice in 2nd now. I don’t know much about 4 speeds (it’s an m20). I get under the car and pull the middle rod (I think it’s 1/2 rod) back towards trunk and it frees up the shifter and I am back in business. Any thoughts on how I should troubleshoot? Thanks guys..
 

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shift in a H pattern not a Z

you have to come straight up to nuetral out of second

then cross over to 3rd

your cutting the corner

or your linkage needs adjusting ....
or

both

original or repop linkage ?


ever put the pin in the guide hole and adjust the rods ?

scott
 

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Discussion Starter #3
thanks for help judge. no one told me the H was for real. I am shifting diagonal. how do you shift an H fast!?

With that said, I suspect maybe my linkage needs to be adjusted too. I don't know if its original or repop. PO made the car pretty much period correct but not numbers matching. How would I tell if repoo? I dont know about the pin guide - although I do have the shop manual and recall seeing a pin guide in the schematic. is it easy to describe what I am generally supposed to do adjust the linkage?

one other thing to mention that may support linkage adjustment - shifting even when just cruising is sometimes not smooth - i have to baby it into second sometimes as I get some initial resistance
 

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Stuck in 2nd

Hey guys- had an odd thing now happen twice over last month. I punch it in 2nd and when I go for 3rd gear it does not happen. The transmission is then stuck in 2nd. Driven home twice in 2nd now. I don’t know much about 4 speeds (it’s an m20). I get under the car and pull the middle rod (I think it’s 1/2 rod) back towards trunk and it frees up the shifter and I am back in business. Any thoughts on how I should troubleshoot? Thanks guys..
I thought I was the only one that had that problem. But mine is on my 1974 camaro Z28 not my Gto. I have a rebuilt 4 speed muncie and a rebuilt oem itm shifter. I thought it was my shifter but now I think it may be my trans or linkage. I Have set my linkage with a allen tool thru the shifter in neutral several times with no luck. Mine has never done it while driving only when I am trying to get it in reverse. hopefully someone has solved this issue.
 

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had that problem with my Muncie 3 speed. Would also jam between gears.

The linkage was out of adjustment
One of the shifter arms was worn and rotating on the shifter ear (moving the shifter wasn't moving the shifter fork in the transmission)
The bolt holding the shifter arm was the wrong depth.

Took care of the adjustment, had the arm welded and I drilled it out and used the correct bolt size and some loctite red.
Working fine since.
 

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something to try........
always go into first before going into reverse
reverse uses several 1st gear gears and parts
jumpin from any other gear they can be moody
and it really helps to go into 1st the around the corner to reverse
just have to remember tom come all the way out of first brfore doing the loop to reverse .....
Scott
 

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Discussion Starter #7
ha. yeah its annoying. I did just pull out the shop manual and believe i now understand how to adjust the linkage with the pin. I assume I can use anything that fits in the hole - like an allen wrench or similar. will update any progress. supposed to snow tomorrow. lets see how the weather holds up...
 

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Discussion Starter #8
thanks Indian. ill look at the rod and the ear too and see if any play or movement that may lessen shift action
 

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Shifter/linkage out of adjustment. Line the arms up with a 1/4" drill in the hole with the shift rods off, then adjust the rods to fit. Remove drill bit. Also, the shift arms that connect the linkage to the shift forks inside the trans can come loose on the earlier linkage. This is easily tightened on the outside of the box where the arms connect with the linkage. With a Muncie and a Hurst shifter, I simply slam the shifter from 2nd towards the passenger side wing window....straight diagonal shot. Nobody follows the 'H' pattern, unless they like losing races and going slow. There are all kinds of youtube videos on shifting one of these cars....if you're brave, queue up Bill "Grumpy" Jenkins powershifting his '69 Camaro. Absolutely bitchin'....and brutal.
 

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"Nobody follows the 'H' pattern, unless they like losing races and going slow. There are all kinds of youtube videos on shifting one of these cars"

x2. I shift the same way, 4-speed or 3-speed. Never used the "H" pattern unless I had a shifter/linkage problem. :thumbsup: 3-speed on the column? Whole 'nuther story. :yesnod:
 

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I have been so lucky over the years, (younger foolish era) at the races, 4sp shift without lifting my foot off of the gas peddle. :bannana: I once came home at the end of a tow hook when the oil pick up fell off @ ~ 90mph. That led to my first rebuild.
 

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Shift in an H pattern. I have a 65 and had the same issue. Went under car and checked linkage and it was fine but sprayed some lithium grease for good measure and have had zero issues.
Don't worry about shifting fast, you're in a goat so chances are you are out in front of whoever was next to you. :)
 

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Discussion Starter #15
Coming back to this thread. I had a local guy put the car on a rack and adjust the linkage. Did not really solve the problem. The mechanic suggested that the shifter itself might be worn inside. Seemed to suggest the when I shift, the stick moves, but it does not catch the rod to actually engage a gear. Has anyone heard of something like this?

He suggested I replace with a hurst super shifter. If I go that route, would that bolt in, and could I use my existing curved stick shift, vs the one that stands straight up with super shifter?
 

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shift in a H pattern not a Z

you have to come straight up to nuetral out of second

then cross over to 3rd

your cutting the corner

or your linkage needs adjusting ....
or

both

original or repop linkage ?



ever put the pin in the guide hole and adjust the rods ?

scott
Bingo! The proper adjustment is critical. If you can put a wrench on the shift levers (on the transmission itself) and changing gears (move the lever forward and back, then your internals are most likely fine and you just need to properly adjust the linkage (ask me how I know).

When looking at the linkage, look to see if the plastic bushings are broken or there is excessive slop (another culprit).

Good luck
 
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