HI... new to the site
I have had a 46 Stylemaster for a little while now and have been trying to master the 3rd to 2nd gear down shift... Is it normal for the tranny to grind if I dont lets the revs come WAY DOWN before a shift???... 2nd gear to 3rd is not problem, but coming down, man that hurts sometimes... Is the 3rd to 2nd gear shift supposed to be synchronized??? Could it be the sing of a transmission problem??? A used synchro??

Thanks for the help...

Marcellin

If your car is still equipped with the vacuum shift it will be necessary to make a more deliberate shift. Speed/down shifting with the vacuum assist is not anticipated in the design.

Along with what Ray said the syncro may be a little weak.More common on these is the little crunch from 2nd to 3rd as the vacuum shift forces in 3rd gear a little faster and wears the syncro. ring.Also depends at what speed you are attempting the shift.Over 25 MPH may be a little too much for it.

My car still has the Vacuum Assist and it works extremely well from 1st to 2nd and 2nd to 3rd, nice and smooth, no crunch of any kind... I can downshift from 3rd to 2nd smoothly, buy I have to be going very slow, not sure how slow exactly (car is put away for the winter and I can not test it in short order)... AntiqueMechanic, are you telling me that it is the Vacuum Assist that prevents me from downshifting smoothly???

No, the shift will be smooth, however it must be done slowly. When shifting, pause briefly in neutral as you go through it.

I do not wish to have you believe the vacuum shift is a problem. It is designed for ease of shifting in a time in our history that we were not in a BIG hurry.

No the vacuum shift is not the problem, the shift from 3rd to 2nd in your car is not like a skift from 4th to 3rd in a modern rice rocket. The straight six has so much low rpm torque that second is only an intermediate speed. there should not be much of a need to "Gear down" until the speed is much more slower. As Ray said take your time, if you feel you should need to be in second to pull a hill or decend a steep hill slow down and go to second before the decent or the climb, other wise when you quickly shift down to 2nd there will be the grinding. At least it always has been for me. I rarely stay in second and wind up the engine as one would in a v/8 or a rice rocket. I have seen those that insist upon gearing down even when a stop sign is in view. That is not recommended in a straight six with 3 on the tree vacuum shift or not.

All the above is correct! After 19 years of work I just got my 47 driving this summer. It just does not compare to "TODAYS" standard of 4 speeds. The best description is Mrmacks 4th to 3rd downshift. And as Gene stated downshifting from 3rd to 2nd over 25. This engine, and transmission just wasnt made to withstand this.
It took me some getting used to as well. I never downshift into 2nd unless im under 15 mph, as any faster, and it makes for an unpleasant experience. Once you understand how she was designed, and accept the brilliance of its simplicity, Then do what I do. Put on your finest wool hunting jacket, and your best beaver skin wide brim hat. Find a good oldies big band station on that deluxe radio, and head out to the country roads!!! If you dont look too closely, you could swear its 1947 again........

....A man after my own heart, Fleetmas47 if you have your vintage sweetie with you, enjoy a nice conversation ... "Ain't this the way livin' should really be?"

You said it Mack!!! I was born in 63, but have ALWAYS been in love with the 40s. Without a doubt, my FAVORITE time period!!! I guess I was just born 30yrs too late But my 47 is my time machine

Actually the vac shift is part of the problem - and was normal when new.

My '39 with with the same transmission but a floor shift can be shifted from 3rd to 2nd at any speed without crunching.In the mountains I have down shifted many times at 30-35 MPH with no problem.Especially necessary since converted to the 3.73 rear end.I don't down shift in regular driving unless at a very low speed out of respect off old age-both me and the car...