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
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
A plantetary gearset is most certainly composed of several gears. In simplest
center (sun) *gear* with usually three or four pinion *gears* meshing
with the sun and an outer, internally-toothed 'shell' *gear.* They may
be helically cut, but gears nonetheless. The hydraulic portion of the
transmission serves only as 1) lubrication, 2) torque
transfer/multiplication in the converter, and 3) manipulation of the
Simpson powertrain's (compound planetary *gear*set) members via various
clutches/bands to provide the drive,
driven and held members necessary for the various reductions and OD
On Tue, 06 Jan 2004 06:02:52 -0700, 351CJ wrote:
remove 'spamsucks' from mail addy for replies.
I fart in Darl McBride's general direction.
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
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
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-)
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.
Mike, we are talking about the AOD, it does not have a locking converter. Now,
All CURRENT automatics offered by ford have locking converters, up till 94 not
all did. The Tempo/Topaz did not. The 91 Crown and it's sisters did not ( any
car or truck with AOD sold 91 and earlier ). The C6 was still offered well into
the 90's, it did not have a locking converter. I don't believe the Asian ATX had
a locking torque converter.
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. ;)
Thomas Moats wrote:
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.
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