I would love to be able to disable the automatic feature only - that is, I'd love it if it only kicked in when I wanted it to. Is that possible?

 

I have a 88 w/4+3. 29,800 mi When I hit the O-Drive it will not go into OD. With the OD light on if I let off the gas the engine will free-wheel like I have put in the clutch. The car will run fine but no OD, with the OD off the car drives like a normal 4-speed. I have all paper work on the car since new. When new they had problems with the OD switch. The second owner had th OD unit rebuilt @ $2,600 the car sat since 1999 till I just got it. Any ideas?

 

Have you checked the transmission fluid in the OD? It can only be checked from under the car, and make sure that it is the OD and not the transmission.
Unfortunately, not many mechanics know this unit. My neighbor owns a reputable transmission shop, I asked him to look at mine and he said that he did not
like working on them and that if my OD works dont mess with it! so with these words of advice, find a known corvette xmission mechanic and have them look at it.
Find a local corvette club, or maybe someone on this forum who is local to you who might know a good shop.
Tom-

 

My OD only kicks in when I enable it with the button, and I have OD in 2nd thru 4th. It sounds like maybe some has elininated the shifter switch or the switch is broken and
you OD is on all the time. Is the OD light illuminated on your console ? if your OD light is on and you press the shifter switch, it should drop out of OD and not go back in to
OD until you press the switch again.
Tom

 

Mine is functioning as designed by GM - yours has been Gerry Rigged to work only when you use the button and I wish mine did that as well. However, you should never run the car in 1st Gear with the OD on as this will damage the tranny in time. GM never intended the OD feature to be engaged in 1st gear.

 

Yes the OD light comes on when I hit the OD button. There is no change in the RPM @ 70 mph the rpm is about 3,100. And the up shift light keeps coming on. When in OD if I lift off of the gas the engine RPM goes to idel. With the OD off the engine will brake the car like a normal 4-speed. I have not ckeck the OD unit for trans fluid yet, I plan on putting it on a lift this Saturday.