I have a 1978 Chevy K10 not shifting into 3rd gear 350 motor 300 tranny
Drive truck for 3 weeks ran fine transmission will
go into 3rd sometimes sometimes it won't. I
replace the vacuum assist and transmission flush
filter new fluids
Time for it to be rebuilt. Could have prolonged it but since you did a flush on it, your going to have nothing but problems with it.
Has anyone used seafoam transmission treatment
Can the kick down cable keep from going into 3rd
That is something to check out. Maybe it is tight.
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