Talk:Overdrive (mechanics)

message: Hi:
I need to know when would it be apropiate to use the OD on or off, I live in Mexico City a very crowded town but I really dont know when to use the OD on or off, should I turn it off inside the city or what.
THANK YOU I'll WAITING FOR YOUR ANSWER.
 EMAIL: rafaelg@rocketmail.com
-----------------------------------------------------------------
Rafael, 99% of driving should be done with the overdrive enabled.
Posted some edits, forgot to give references.
http://www.ohiovw.com/files/touaregfiles/6speedautotranny.pdf
http://bandwidthmarket.com/resources/patents/apps/2002/7/20020086761.html
 http://www.sae.org/servlets/productDetail?PROD_TYP=PAPER&PROD_CD=2005-01-1020
http://techinfo.toyota.com/
Sorry, last two are pay sites, unfortunately that is where most of the good stuff,
with lots of details is. 
3sgte 16:35, 2 December 2005 (UTC)
replies: text: When you start your car, many cars (such as the Nissan Altima) default to the state of the Overdrive being turned ON.  You might find a button somewhere that takes it OFF, however. 198.177.27.23 (talk) 07:50, 19 October 2008 (UTC)
thread_title: Untitled

message: When reading this artice, I notice that manual transmission was only mention once, with the remainder of the artice favoring OD in automatic transmission. I think this is Bias. 
--KB1KOI 15:32, 28 July 2006 (UTC)
thread_title:  Bias Toward Automatic Transmission 

message: I'm trying to find consensus for renaming "(mechanics)" pages, where "mechanics" refers to machinery, mechanisms, mechanical devices or mechanical engineering, rather than (e.g. classical) mechanics in physics and applied math. I would like to rename this page to "Overdrive (mechanism)" or "Overdrive (mechanical device)" or something similar. Any preferences or objections? Geometry guy 20:57, 21 February 2007 (UTC)
replies: text: Perhaps Overdrive (automotive)? Publicly Visible (talk) 13:58, 4 May 2012 (UTC)
thread_title:  Rename Page? 

message: I read the main article but remain confused as to the usefulness of the "overdrive" button on the stickshift of my '98 Nissan Altima.
The little overdrive button on the side is not the same thing as the big stickshift button on the top.  The little one is located on the driver's side of the stickshift, about three or four inches down from the top.  It's small, and measures about a quarter inch across, so you aren't likely to confuse it with the relatively larger stickshift button on the top, which measures about 2 by 3 inches.  You change gears (like, going into reverse) if you push the big button down, and then pull the shiftstick back into the appropriate gear.  But what on earth does the overdrive button do?   I've heard gossip that it is useful when driving at high speeds.
In my case, the car is almost always in "overdrive" mode, but if you decide to press the overdrive button, it goes in a bit, so it is flush with the rest of the stickshift.  Then a dashboard light comes on, and it says "O/D OFF" but what is even more interesting, the car's RPM will go up.  This happened lately while I was driving in the 45 to 55 mph range. 
Am I getting better miles per gallon if I am driving 50 mph on a relatively level road with the O/D button pushed in, so the overdrive is off?  198.177.27.23 (talk) 04:32, 16 October 2008 (UTC)
replies: text: I have no knowledge of the'98 Nissan Altima and even less about the US version of it but overdrive works always the same way. Simply put: The overdrive works similarly to changeable differential. If you switch the overdrive off it is if you would cruise at smaller gears. It causes your engine rpm increase at the same vehicle speed which means your economy aka mpg drops but you gain more pulling power (torque to the wheels increases). I would assume that in this case overdrive should be switched off only when additional pulling power is required, for example when pulling loads or moving in difficult environment like climbing a steep hill... Hopefully this helped...  —Preceding unsigned comment added by 80.223.93.188 (talk) 22:27, 4 December 2008 (UTC)
thread_title:  overdrive on a '98 Nissan Altima 

message: At least on a '98 Nissan Altima, pushing the Overdrive Button in (so the O/D OFF light comes on), the rpm's go up.  Does it make a difference if the car is being operated with the Cruise Control switch on?  198.177.27.16 (talk) 20:30, 16 October 2008 (UTC)
replies: text: Cruise control is a separate system, a device with a sole purpose to hold the vehicles speed steady by adjusting engine rpm. It should have no effect to the overdrive: In other words driving with overdrive off your vehicle consumes more fuel wether you use cruise control or not. As stated before, in this case overdrive should be used unless extra pulling power is required...  —Preceding unsigned comment added by 80.223.93.188 (talk) 23:56, 6 January 2009 (UTC)
thread_title:  Cruise control versus Overdrive 

message: :an overdriven ratio for cruising thus required a gearbox ratio even higher than this (1:1), i.e. the gearbox output shaft rotating faster than the original engine speed.
Isn't this backwards? An overdrive gear's ratio will be less than 1. Typically around 0.75.
20:19, 17 August 2011 (UTC)
replies: text: That section (Introduction) is discussing the transmission overall, not a separate overdrive unit specifically. It's difficult to be unambiguous here, as the transmission reduces engine speed to final drive speed, thus the ratios are somewhat inverted between common discussion and their numerical values.  1st gear is described as "low" and top gear is described as "high", even though their ratios are probably 3:1 and 1:1 (approx) - so the "low" ratio is numerically higher than the "high" ratio. Presumably this stems from a natural tendency to describe ratios from whichever direction is greater than 1, not the fractional value. These words have far more common usage than the numbers do, so I've used them to describe the ratios. Overdrive might well become 0.8:1, but we'll still call this a "higher" ratio, not a lower one. Andy Dingley (talk) 23:14, 28 September 2011 (UTC)
thread_title:  overdrive gear ratio 

message: There is an excruciatingly popular (and stupid) misconception that Overdrive Gear refers to any gear with a reduction ratio of less than 1. This is completely wrong. Overdrive Gears almost always have reduction ratios of less than 1 but not all such Gears are Overdrive.
I'm glad to see this article got it right.  — Preceding unsigned comment added by 95.76.145.55 (talk) 22:51, 18 October 2011 (UTC)
thread_title:  Hugely popular mistake 

message: I really like this article, but the beginning relies on one source from 1976, and every section but Overdrive (mechanics)#Overdrive in Europe is unsourced. More WP:VERIFY would take this from good to excellent :) Publicly Visible (talk) 13:56, 4 May 2012 (UTC)
thread_title:  Single source May 2012