A500 Trans. overdrive problem

I have the overdrive on my A500 in my Dakota hooked up to a switch. It was working fine til I was driving 55-60 in overdrive and it was like some one through an anchor out. I switched out of o.d. and it worked fine in 1,2, and drive. Put it back in o.d. and it binds up again. What happened?
THANKS, Curt

Sounds like your OD planataries are bugered up. You can remove the OD section with out removeing the rest of the trans and fix it.