Tranny not shifting into overdrive

[dogbone]

My tranny won't shift into overdrive, it shifts fine from 1 to 3, I changed the filter and put Royal Purple in it, anyone got any ideas?

[grinders_18]

....fourth gear is gone?  :icon_frown:

I hope not, but maybe that's what happened?

[cobracmdr]

Did it go into lockup before the oil and filter change?

[dogbone]

Not sure what you mean by lockup, but other than shifting a lot smoother now it is the same as before, not going into OD. I was reading in the manual about adjusting the TV cable?

[jimmy]

              Then I'm affraid you have serious problems. Here's the list of possible causes.

[Bullet]

I would check the control valve.