True Overdrive?

I have a 1983 Mercury Grand Marquis, I guess it's just an AOD transmission.

I've heard people tell me both ways..... so I'll ask here:

Is the "overdrive" truely an overdriven gear? Or is it 3rd with a locked torque converter?

Nic

Reply to
Robotnik
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The only gear in an automatic transmission is park. They are fluid driven, there are no gears.

transmission.

Reply to
351CJ

Reply to
Thomas Moats

Reply to
Thomas Moats

As cute as you think your answer might be, it has nothing to do with the op's question. Although there may be a "planetary gear set" it is NOT "gears" as the op was inferring..

Reply to
351CJ

WHO was the original clown with the "cute" answer ?

The world refers to transmissions (auto or not) as having "1st gear, 2nd gear", etc. Yet, you chose to get semantical and provide zero value to the thread.

Reply to
Mark

The Ford transmission all have a locking converter as well as an overdrive gear, in both their current 4 SP and 5 SP automatics.

mike hunt

Robotnik wrote:

Reply to
MikeHunt2

uhhhh...... I might be missing the point..... but I don't think my transmission is "current"

Nic

transmission.

Reply to
Robotnik

Well, you have made a lot of posts here... you seem to know what you're talking about as far as I can tell. So, I think from now on, I will beleive that my transmission has an overdriven 4th gear ratio without a locking torque converter.

It's too bad we can't assume every once in a while what one is talking about, instead of getting extremely technical on what the webster's meaning of certain words are... such as "gear"....

Thanks, Mr. Moats 8-)

Nic

transmission.

Reply to
Robotnik

I'm pretty sure that the hydraulics in an automatic transmission actuate clutch packs which act upon gear sets, Sun, Ring and Planetary Carrier. All of which give you different ratios. Different then a manual transmission gear set but gears all the same. To answer the original poster. The AOD 4th gear has a ration of .67. Which is overdrive.

Pat

Reply to
PATRICK T. DAVIDSON

Thank you, the ratio was more than I needed to know. But thanks anyway. :)

Nic

Reply to
Robotnik

NO, the AOD is a direct-connect (the converter is bypassed by a long shaft through it) to OD planetary to driveshaft in OD(4th "gear"). The converter is just along for the ride in this mode.

Rob

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Reply to
Trainfan1

Reply to
Thomas Moats

Reply to
Thomas Moats

Reply to
Thomas Moats

Not quite, the converter housing drives the direct clutch giving you 3rd and fully mechanically linked. When you are in 4th there is a 60/40 split of torque,

60 percent of the power flow is thorough the direct clutch the other 40 percent of the power flow is though the turbine of the converter. There is no overdrive planetary, the AOD uses one compound planetary.

Reply to
Thomas Moats

I know. I should have added that his does not have the locking converter. I was attempting to covey that it does have OD, but I type fast and only spend a few minutes in any NG. ;)

mike hunt

Thomas Moats wrote:

Reply to
BenDover

Reply to
Marky

Your responses are the cutest......smile.. :-)..!

Reply to
V.B. Mercon

transmission.

Overdrive is truelly overdrive. The output shaft is spinning faster than the input drive. However, what is more important is that the car's engine is spinning more slowly, which reduces wear and tear and gas consumption.

Jeff

Reply to
Jeff

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