Post your rpms at 70mph

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Datach - Good question - I should check speedo against GPS. However, odometer is almost right on based on mileage markers - perhaps 1% slow. (I.e. It racks up 9.9 km on a 10 km test section.) As well, the fact the calculated & observed RPM values are the same at an indicated 100 kph tells me that the speedo is very close.
 
Remember the odometer is directly geared to the driveshaft. As long as the tires are the right size it should be right on.

The speedometer is a completely different kind of instrument. I think it uses a spinning magnet tugging on the needle. How easily the needle moves on its bearings can affect the reading.

Not so with digital speedometers, of course.
 
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Looks like 1900RPM at 70MPH for me.

1999 Ford Expedition, 5.4L V8.
 
Originally Posted By: MalfunctionProne
Backlit:
*same '99 Ford Expo

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My F150 with RAR of 3.55 reads about 2000 RPMs at 70. The Impala with the 6 speed auto is at about 1600 or so - I haven't tested it with a scan gauge, but the in dash RPM gauge is reading a needles width or so above 1500 at 70 MPH. The Mercury according to the "Torque" program is about 1700 RPMs with the 2.73 RAR. The Camry is right around 2,000 RPM IIRC.

Years ago I had an 1982 Ford Escort station wagon with the 1.6 engine and 4 speed manual. At 70 the RPMS were about 3,500 RPMs!
frown.gif
 
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Originally Posted By: Kory
Cruze Diesel....exactly 2k rpm @ 70mph


what transmission?
 
2005 Chevy Avalanche 4L60E trans, 3.42 diff gearing. 1800 rpm's at 65 mpg and 1950 rpm's at 70 mph. I just checked it on my morning biscuit run.
 
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