Eugene Weiser

Hi, did a complete rebuild on my trans (lost reverse broken sun shell). My question. I have not installed trans yet, and not added fluid yet. I wanted to check that everything turned freely and parking locked up properly. It does. When I shifted into reverse (trans out of car and still on bench) I shifted into neutral, drive shaft turns by hand in on direction, same with reverse and all other gears. Tried to turn by hand in reverse and will not turn opposite direction, only counter clockwise, same as the other gears.

Is this normal since no fluid in trans, or did I fubar something and need to tear down again? Any help would be appreciated.

Thanks

Gene

mrvedit

The driveshaft will turn fairly easily in one direction, but should turn in the other direction too, just much harder, maybe 3x harder. In the easy direction (forward direction?) the low/reverse clutch is letting it spin, In the hard direction the sunshell and inner parts of the input drum turn and these parts have a lot of friction.

Did you bench test the input drum with air pressure? Even better is to install the input drum into the pump and air test that assembly.

Eugene Weiser

I air tested as I was rebuilding. I followed the ATSG Manuals to the letter. Replaced the sun shell, checked clearances, replaced all seals, Teflon rings, o-rings, etc. I was hoping that maybe because I have not added fluid yet (did not want it pouring all over while installing) that may be why I am not getting engagement. Also, the Torque converter turns free in all gears, even park. I rebuild engines, and wanted to tackle this one myself with some patience. clutch pack were good, clearances showed little wear and end-play was well within tolerances. Looks like I may need to install and try with wheels on jackstands bought an extra sunshell just in case.

mrvedit

Think about it - the engine has to be able to run in Park and the torque converter is attached to the crank.
Sounds like you took the time to rebuild it carefully and are now over-thinking it and over-doubting yourself.
If you have little ATF in the trans I suspect the output will be very hard to turn in reverse (the hard direction). The frictions should have been wet when you assembled the input drum. If not, add plenty of fluid, let it sit for a while as you regularly turn what you can.

Eugene Weiser

mrvedit. You are most likely correct. Over thinking and doubting. I got to thinking about it today at work and realized that there needs to be fluid to activate everything. Thank you for your help it is greatly appreciated. I soaked everything in tranny fluid overnight before assembling to make sure they did not dry out and to have some fluid on the working parts. Must say though that rebuilding a trans is much different from an engine and though more parts, I did have fun

Thanks again
Gene