who drives without o/d?
Senior Member
Joined: Mar 2000
Posts: 1,985
Likes: 1
From: Cincinnati, OH
Most of all of that is urban myths.
The PCM has rules or when to shift and that's when the computer determines it should shift for the result it's calibrated for. Most of the time the calibration is more for fuel economy, and for that it's set up correctly. The thing about not towing with it is not true, it's fine to tow in OD, but admittedly when it hunts for the gear it wants it can get a little nerve racking, and that's why the switch is there, mostly. Also, there are situations where it's nice to have it for engine braking, so that's okay. But it won't hurt a ting to leave it on, won't weld the O/D shaft to the Input shaft (actually, they both turn in 3rd gear, two.) won't hurt the sprag, it's designed to find the most fuel efficient gear and that's what it does, but sometimes it gets "too much information" and changes it's mind every 3 seconds, and you can turn it off them if that annoys you (it does me) but there is no need to if you can handle the agravation.
Now, there are a lot of times where it can do some damage when you have OD disabled, but form the most part it doesn't hurt anything except your mileage.
When OD trannies first came out, a lot of people just couldn't get used to the searching for gears, and with towing in hills it gets pretty bad, that's why they put it in there.
G
The PCM has rules or when to shift and that's when the computer determines it should shift for the result it's calibrated for. Most of the time the calibration is more for fuel economy, and for that it's set up correctly. The thing about not towing with it is not true, it's fine to tow in OD, but admittedly when it hunts for the gear it wants it can get a little nerve racking, and that's why the switch is there, mostly. Also, there are situations where it's nice to have it for engine braking, so that's okay. But it won't hurt a ting to leave it on, won't weld the O/D shaft to the Input shaft (actually, they both turn in 3rd gear, two.) won't hurt the sprag, it's designed to find the most fuel efficient gear and that's what it does, but sometimes it gets "too much information" and changes it's mind every 3 seconds, and you can turn it off them if that annoys you (it does me) but there is no need to if you can handle the agravation.
Now, there are a lot of times where it can do some damage when you have OD disabled, but form the most part it doesn't hurt anything except your mileage.
When OD trannies first came out, a lot of people just couldn't get used to the searching for gears, and with towing in hills it gets pretty bad, that's why they put it in there.
G