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How does the 4+3 Manual Transmission Overdrive work?
I was looking to buy a late 80's corvette with a manual transmission and a seller was telling me that the button isn't in the stick anymore and when he is easy on the car it automatically goes into overdrive and when you are hard on it, it stays in the regular gears. Is this how the transmission suppose to work?
The O/d is on every time you turn the key on.
When the right conditions are met ( varies by year ) , speed / engine temp /TPS volts; the O/d will automatically engage.It will also kick out back to direct drive when certain conditions are met ( hard accel, etc)
The O/d can be turned off by using the button and then manually engaged when ever you want to
In my early 1985 the O/D is never on automatically when the key is turned on. You must engage or disengage the O/D with a switch on the console. Later on the switch was mounted on top of the gearshifter. Otherwise it's just a T10 4 speed transmission. You can use O/D in 2nd 3rd or 4th gear. Just a note that the early 4+3 transmissions were very durable. Just not many people ever really knew how to use them and wound up damaging them through misuse.