Just put a new rebuilt 700r4 trannie in my 40 coupe. Its behind a pretty much stock 350 motor. On the second shift, that is going into third gear it makes a clunk. I had the transmission guy build another. And the new one does the same thing. He said he will stand behind the it, but doesn't know what it is. Has anyone had this problem with a 700r4? Thanks Mark.
The 2-3 shift clunk is due to the timing of the shift being less than perfect. A servo has to fill with fluid pushing a piston witch pushes a pin to release a band holding a drum and at the same time a clutch pack has to apply to make the shift. The length of the pin, the clearance between the band and drum and the clearance of the clutch pack all mix into the equasion as to when the shift takes place . If the pack applies too fast the trans will bind if the band releases fast and there is time before the pack applies there is a clunk( your splines have time to unload). There are ways to( adjust the timing ) of the shift, but all in all it shouldn't affect the life of the trans.
Thank you for all the info, I won't worry about it self destructing. Can the adjustments be made with trannie in the car?
The trans would have to be disassembled to change the band or adjust the clearance in the clutch pack. There are aftermarket shift kits and I have read on some forums about different methods of improving shifts while in the car. Google 700r4 2-3 shift clunk
Yes, my 350/700R4 had that same clunk. I always figured it was U-joints or excess ring and pinion backlash. I did fluid, filter and refilled it to factory specs after repairing a minor leak issue a few years ago, all was fine except the clunk . To make a long story short, I measured out a pint of Dextron III, poured it in today and the clunk went away. I remembered reading this, might be worth a try if you're still having issues.
Get the tranny guy to adjust your TV cable for you that way you are both sure that it is not the problem. next check and make sure it is a tranny problem and not a drive shaft problem, I have seen bad U joints and loose output shaft couplers do clunks and sometimes they are not what you would expect them to do. They way your tranny shifts can be adjusted with different springs in the governor on that tranny a kit will run you about 30 buck these days I think. The governor is that little deal under the domed cap with the bail on it. You can do it all with the engine in the car. No muss no fuss. Just some things to think about.
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