No Go Forward

[buickboy]

Broke a rear u-joint last week after a high boost launch. Got the driveshaft back in the car this week and backed it up off the trailer. put in drive and it would load the mtor, but no go. Rev the motor and car would just sit there. Transbrake will engage, no external leaks and trans is full of fluid. Goes fine in reverse. Looking for some experienced troubleshooting please. Trans has lots of billet parts, and a 19930 Art Carr billet cover 3500 convertor brand new.
thanks for any help
Mitch

 

[buickboy]

I am told that it is most likely the sprag. Anybody else care to take an educated guess?
Mitch

 

[77 cruiser]

If it's the lo roller clutch-sprag it should go in manual lo.

Jim

 

[buickboy]

Jim-
I was using my stageright transbrake that uses Lo gear as the SR activator so cannot use your suggestion. Thanks for the only response in four days.
Mitch