727 guts question

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chryslerfat

chryslerfat

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I have a 76 car trans I took apart and put the guts and valve body in from a 77 Winnebago 727. The reason I did this is to have a slip yoke instead of a bolt on yoke. My question is the servo piston that is exposed when removing the valve body from the car housing there was a heavy spring pushing the piston down and nothing under the piston. The guts I used from the truck trans had nothing on top of the piston and a small spring pushing the piston toward the valve body. Which is correct??
 
I know most shift kits require removal of the heavy spring pushing the piston down.
I am assuming the motor home one is set up for firmer shifts.
 
the spring goes against the valve body but have no fear. toss it in the trash can. you can leave it out or you can make a rod, i forget the exact length, that is just long enough to put between the piston and trans case bore that enables you to reenstall the valve body back on, a little slop is fine. this is the very basic shift kit you can do. the piston is called an acumulator servo and solfens the shifts.
 
Ok so what I did was probably ok. I used the servo and small spring that was between the servo and the case from the RV and reinstalled the RV valve body so it is just as I took it out of the RV valve body. Thanks for the fast reply. BTW the reason I used all clutch packs and valve body is the RV trans only had a couple thousand miles on it and the car trans was unknown.
 
Just for reference I've seen them built both ways you described. I usually do what Bob says and toss them and put a blocker rod in it to make it shift firmer. Only exception is if it's for a person who wants a stock smooth shift. Even then I use the lightest spring i can find to make it shift a little better. A light spring will compress faster allowing the band to clamp down faster making for a better shift.
 
440 cars had the spring on top of the piston, others had the spring on the bottom.

The procedure described earlier about measuring the spring and using a piece of pipe the same length as the spring instead of the spring is actually in the 1974 Factory Shop manual I have for A-bodys. The result is a nice, firm 1-2 shift.

You can also adjust the line pressure up a bit, its easy to do and will make your shifts a little more firm.
 
Im about to rebuild a RV tranny for later use in the Dart but my question is did you disassemble the tranny and notice any differences such as heavier duty internals and extra clutch disks?
 
............Trucks, vans and motor homes have HD internals...big boat cars......police also..........HD+Performance cars had the little spring under the accum...........u can also block the shuttle valve.......opposite side of filter;.....5 screws on top plate ..2 screws on side.....take out spring.use 1/4 in rod..............kim........
 
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