2012 Ram Trucks Receive New Six-Speed Transmissions
http://news.pickuptrucks.com/2011/06/20 ... sions.html
The Ram truck brand is increasing the number of gears available for its 2012 light- and heavy-duty pickups with the introduction of two six-speed transmissions.
Light-Duty Ram Transmission Changes
The 2012 Ram 1500 half-ton sees the previously offered 545RFE five-speed automatic gearbox recalibrated and upgraded to take full advantage of the split 2nd gear, so all six speeds are available to the driver in a newly available "Electronic Range Select" mode.
The 545RFE transmission was unique. Even though it was identified as a five-speed transmission, 2nd gear was split into two cogs, depending on whether you were upshifting or downshifting. On the way up, it was 1.67, but there was a 1.50 "kickdown" ratio on the 3-2 downshift to smooth out what would otherwise be a large gap between the gears. Fourth and 5th gears were overdrives for improved highway performance and fuel economy.
Electronic Range Select mode lets the driver manually limit the highest available transmission gear, allowing manual upshifts and downshifts based on road speed and engine speed. It's especially useful for towing through hill country when the climbs and descents are closely spaced together.
The recalibrated 545RFE in the Ram 1500 is now called the 65RFE automatic six-speed.
In full auto-shift mode, the 65RFE behaves the same as the old 545RFE, keeping the split 2nd gear and kickdown behavior. Also added is a new torque converter that's expected to marginally improve fuel economy, but not enough to boost EPA mileage ratings.
The 65RFE is standard with the 4.7-liter V-8 and 5.7-liter Hemi V-8 gas engines.
Heavy-Duty Ram Transmission Changes
The 2012 Ram 2500 Heavy Duty pickup also gets a new six-speed automatic transmission, called the 66RFE. It replaces the previous Hemi V-8 gasser's 545RFE gearbox, which was shared with the light-duty Ram.
The 66RFE transmission is a hybrid of sorts. It combines the internals of the 68RFE heavy-duty six-speed automatic (including the gear ratios) that's paired with the 6.7-liter Cummins six-cylinder diesel engine and repackages them in the 545RFE's case.
Like the 65RFE, the 66RFE offers Electronic Range Select to lock out gears on demand.
The 66RFE is standard with the 5.7-liter Hemi V-8 on all Ram 2500 models.
