4020 sychro adjustment

Roger in Iowa · Nov 29, 2012

I know I have read solution but cannot find it.

1970 4020 sychro, overshifts in the higher gear of the range, i.e. 3, 5, 7 and 8. All work, but just have to carefully get it in the above gears. 5, 7 and 8 worse but have learned to not shift it so far downward on these gears.

Have cover off for other reasons so now is the time to fix.

Thanks for help.

Jim Knapp · Nov 29, 2012

Might just be the clevises on the shifter rods from the shifter under the dash to the transmission.

Jim

Tx Jim · Nov 30, 2012

Roger is there very much side to side movement in the shift quadrants in the dash?? If so it needs to be shimmed.

tim s · Nov 30, 2012

Put new bushings, clevis and pins,shims in the upper shifter to start with, the adjustments is basically centering the shifter in each gear. Also I have seen the shifter pivot pin get loose and wear the hole a bit, when this happens I pean the hole to "swell" it enough to hold the pin, then goob it up with some JB weld to fill in the void them tighten it up good and let it set for a day. This works fairly good most of the time, but only if you swell the hole first and then depend on the JB weld to finish the fit...And if this don"t solve the problem get the splitting stands out.....

tomstractorsandtoys1 · Nov 30, 2012

Tim have you ever replaced the pointers behind the plugs on the side of the trans that go against the cams? We replace them with a ball and retainer like the later 4230's used,it seems to help center the cam better as many are wore bad from the pointer.We also replace the springs.

tim s · Nov 30, 2012

Yes when I re-build a transmission I include those with the parts, every little bit helps, but "most" of the time a shift problem is worn sychronizers...

4020 sychro adjustment

Roger in Iowa

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Jim Knapp

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Tx Jim

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tim s

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tomstractorsandtoys1

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tim s

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