always wondered this
#1
07-08-2009
#2
07-08-2009
#3
07-08-2009
Join Date: Oct 2006
Location: Virginia Beach, VA
Posts: 193
Likes: 0
Received 0 Likes
on
0 Posts
#4
07-08-2009
#5
07-08-2009
Join Date: Nov 2007
Location: Red Oak, IA
Posts: 2,468
Likes: 0
Received 0 Likes
on
0 Posts
#6
07-08-2009
#7
07-08-2009
#10
07-08-2009
#13
07-08-2009
#14
07-08-2009
#15
07-08-2009
I know I used to use it when I was had my Cruise Control on when I would come to a big hill on the freeway. The tranny shifted smoother going back down to Drive if I did it before the hill rather then just letting it shifted on it's own once I was on the hill.
#16
07-08-2009
That is not OD, the D with the circle around it is drive, and the plain D is basically just 3rd gear. My dads old BII had that.
#17
07-08-2009
Join Date: May 2009
Location: Monroe, OR
Posts: 64
Likes: 0
Received 0 Likes
on
0 Posts
#18
07-08-2009
Join Date: Nov 2008
Location: MA
Posts: 126
Likes: 0
Received 0 Likes
on
0 Posts
Hmmm I wounder I just went out and checked my sis's 2004 Buick Regal (very simmilar drive train to a regular Grand Pix) and the shift pattern goes P R N D 3 2 1. I know she only has a 4 speed auto for a tranny (3 gears and an overdrive) so i believe that if you were to shift into 3 to would be the same as turning the OD off.
#19
07-08-2009
1) automatic shifting is allowed in gears 1 through 4. By locking out 5th gear, it greatly reduces shift hunting at highway speeds.
2) when the O/D is canceled, the transmission's Coast Clutch is applied in 4th gear, making engine braking available. (The Coast Clutch is not applied in 4th or 5th in the default O/D ON mode.)
Without a trailer: O/D Cancel can often provide the same benefits when driving on roads through hilly/mountainous terrain with no trailer. Fuel economy will suffer at speeds above about 45 MPH on flatter roads, so it's a good idea to use O/D Cancel only when needed.
#20
07-08-2009
Hmmm I wounder I just went out and checked my sis's 2004 Buick Regal (very simmilar drive train to a regular Grand Pix) and the shift pattern goes P R N D 3 2 1. I know she only has a 4 speed auto for a tranny (3 gears and an overdrive) so i believe that if you were to shift into 3 to would be the same as turning the OD off.
EDIT: I sort of stand corrected. It appears some times that Overdrive can be a 1:1 to ratio as well:
Originally Posted by Wiki
How an overdrive unit works
The overdrive consists of an electrically or hydraulically operated epicyclic gear train bolted behind the transmission unit. It can either couple the input driveshaft directly to the output shaft (or propeller shaft) (1:1), or increase the output speed so that it turns faster than the input shaft (1:1 + n). Thus the output shaft may be "overdriven" relative to the input shaft. In newer transmissions, the overdrive speed(s) are typically as a result of combinations of planetary/epicyclic gearsets which are integrated in the transmission. In these cases, there is no separately identifiable "overdrive" unit. A number of such transmissions and transaxles are manufactured by Aisin, for use in vehicles produced by many different manufacturers. In older vehicles, it is sometimes actuated by a **** or button, often incorporated into the gearshift ****, and does not require operation of the clutch. Newer vehicles have electronic overdrive in which the computer automatically adjusts to the conditions of power need and load.
The overdrive consists of an electrically or hydraulically operated epicyclic gear train bolted behind the transmission unit. It can either couple the input driveshaft directly to the output shaft (or propeller shaft) (1:1), or increase the output speed so that it turns faster than the input shaft (1:1 + n). Thus the output shaft may be "overdriven" relative to the input shaft. In newer transmissions, the overdrive speed(s) are typically as a result of combinations of planetary/epicyclic gearsets which are integrated in the transmission. In these cases, there is no separately identifiable "overdrive" unit. A number of such transmissions and transaxles are manufactured by Aisin, for use in vehicles produced by many different manufacturers. In older vehicles, it is sometimes actuated by a **** or button, often incorporated into the gearshift ****, and does not require operation of the clutch. Newer vehicles have electronic overdrive in which the computer automatically adjusts to the conditions of power need and load.
#22
07-08-2009
#24
07-08-2009
#25
07-08-2009
i knew that was D with an o around it was overdrive and and standalone D is drive.....doubting myself for a minute...the the original OB, does ur grandprix have the same setup as my gf's escort: a D with an o around it, and jsut a stan alone D that you can select with the gear select?
i know you were mostly wondering "how" overdrive works, but im just curious b/c you said you didnt have "an overdrive button or anything"
i know you were mostly wondering "how" overdrive works, but im just curious b/c you said you didnt have "an overdrive button or anything"
