4r70w guys... Do you run the same pilot bearing?

[TMSVT]

I apologize for a dumb question. I'm building a new motor and wasn't sure . Do I install the same pilot bearing used with the T56 when installing a 4r70w? If not what do I need? Thanks

 

[bubblehead93]

no pilot bearing, the transmission shaft engages inside the converter...

r/
Andy

PS

To answer more fully, you need a flex-plate vice flywheel. The torque converter will bolt to the flex plate. Check the runout on the torque converter before installing on the transmission input shaft. Had no problem with mod motors, but when I first put an SFI flex plate on my first FE motor running a particular manufacturers torque converters I kept snapping torque converter studs. Come to find out the runout on those torque converters were grossly out.. so check runout... install the torque converter and 4R70W as one unit... put some fluid in the torque converter prior to install... sort of priming the pump... think that about covers it....

 

[TMSVT]

I apolOgize . Maybe my question wasn't worded correctly. I do understand how automatics work etc.. I do thank you for your help. But the Trans shaft's tip slides into the back of the crank. There is currently a pilot bearing there for the pre-existing t56. Do I need to replace this bearing in the back of the crank? If so with what? Thanks

 

[03Steve]

First reply is spot on. Remove the pilot bearing and replace it with nothing. Use a slide hammer and it will come right out. Usually, lol

Only thing I would add is to check converter spacing. We shoot for .125-.180 on the local cars here.

 

[TMSVT]

Got it. Thanks to both of you for your help.