I was discussing a car today, and the guy I was talking to has a 1940 with oem stock driveline except car has duals. The car comes out of second gear when descending a hill. Otherwise the trans perfoms normally. He was told 'there is a rod in the transmission that can be adjusted to fix this' (I am skeptical but hey . . .'ya never know) From my dim past with a somewhat shaky memory span, I seem to remember the classic cause for this was worn synchonizers. Is there a chance it could be misadjusted shifter linkage rods? On my '40 Ford and Mercury in the old old days I remember being persnickety about the adjustment of the column shift linkage, and also keeping good bushings in the column arms. Anyway, what I am wondering is if anyone knows of any fixes for this symptom other than pulling the transmission and working on the internals. TIA Henry
You are right 99% of the time the syncro is the problem. The small teeth on second gear or the mating ones on the syncro sleeve or both are worn. One other posiabilty is too much end play in the main shaft letting second gear move away from the syncro sleeve. Same answer the trans needs to come out to fix. Very slim chance of the linkage being the prob.
I had the same problem with my '40 Coupe . Trans is a little worn and when I checked , found it was only 1/2 full of gear oil . Filled it and it stays in gear now?
As mentioned, it could be linkage adjustment, but I wouldn't hold my breath. End play in the early trannys is as much to blame as the synchros. If you open it up, see about fabricating custom thrust washers to tighten things up. The helical gears put forward and rearward thrust loads moving the entire gearset back & forth compromising the engagement of the synchro...
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