4+3 Overdrive tranny question.
Thread Starter
4th Gear
Joined: Apr 2002
Posts: 4
Likes: 0
From: Concord NC
4+3 Overdrive tranny question.
I have a 1988 Vette with the 4+3 overdrive transmission. The car will automatically go into overdrive after reaching a certain temperature. The only way I can get it out of overdrive is by removing the button on top of the shift lever and then pressing down very hard on the little shaft that comes through the shift lever. I can't press hard enough with my finger to make it work. I have to use something hard.
The shaft in question has been adjusted up and down to no effect. Can anyone please tell me what the fix is here? I can't afford to throw parts at it and I would like to be able to drive around town without it always being in overdrive. Thanks in advance.
The shaft in question has been adjusted up and down to no effect. Can anyone please tell me what the fix is here? I can't afford to throw parts at it and I would like to be able to drive around town without it always being in overdrive. Thanks in advance.
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
It sounds like the switch may have come loose from its spot in the shifter. It is held in place with a tiny little nut, and sometimes a zip tie. Remove the center console (requires removing the headlight ****, tilt lever, digi dash bezel and hvac/idiot light bezel) and check it out. A new switch is about $15.
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
Sound like the switch is bad. There was a thread some time ago about getting a momentary contact switch to replace the one in the shifter. Don't recall the specifics but Scorp508 should remember it ( I thnk he was the one who came up with the switch!)
Once the coolant temp hits 122 degrees, the OD will automatically engage. But if you shift into 2nd and hit the throttle so that OD kicks out, it will not come back until you hit the button. It will also kick down in 1st and stay out, but once you hit 4th it will upshift.
Here's an operating guide to the 4+3: http://www.5speeds.com/43table.htm
You might try contacting SKSpeed in New York http://www.skspeed.com/ to see if they can help with the shifter switch.
Once the coolant temp hits 122 degrees, the OD will automatically engage. But if you shift into 2nd and hit the throttle so that OD kicks out, it will not come back until you hit the button. It will also kick down in 1st and stay out, but once you hit 4th it will upshift.
Here's an operating guide to the 4+3: http://www.5speeds.com/43table.htm
You might try contacting SKSpeed in New York http://www.skspeed.com/ to see if they can help with the shifter switch.
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
