Automatic Gears - what is [D]
Thread Starter
Intermediate
Joined: Apr 2013
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From: Roodepoort Gauteng
Automatic Gears - what is [D]
Hi there.
I'm a new Corvette owner. I have a '90 C4 L98 Auto.
Can anybody please tell me why there is 2 "D" (Drive) letters?
As indicated with the blue arrow on this photo.
Thank you.
Henk
I'm a new Corvette owner. I have a '90 C4 L98 Auto.
Can anybody please tell me why there is 2 "D" (Drive) letters?
As indicated with the blue arrow on this photo.
Thank you.
Henk
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
D="Drive" witch is a 1:1 gear ratio; the input shaft is essentially connected to the output shaft of the trans.
The location marked in your pic is "OD" (the "O" is around the "D") and means Over Drive, in which case, the gearing is such that the output shaft spins faster than the input shaft.
The location marked in your pic is "OD" (the "O" is around the "D") and means Over Drive, in which case, the gearing is such that the output shaft spins faster than the input shaft.
Team Owner
Joined: Sep 2003
Posts: 25,373
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An example a 275/17 tire with a 2.59 axle ratio would be something near 2,050 RPM in D (drive), that same speed in OD would be something nearer 1,450 or about 30% less RPM.
Last edited by WVZR-1; May 22, 2013 at 03:53 PM.
