JR - even the non-pedal auto's don't have a torque converter. The have a centrifigal clutch. They engage by revving the engine. Think of it as an overgrown clutch on a cheap go-kart when you was a kid. Some of the clutches may be encased in an oil-like substance (wet clutch), but it's still a mechanical clutch. The trucks with a clutch pedal have the exact same clutch that's in a standard-shift truck.
In other words, the autoshift tranny's are the exact same as in a standard shift truck. The only difference is that in place of the shift lever plate on the top of the tranny, there is a plate which holds 2 small electric motors (XY shifter) that does the work for you. In fact, you can convert between a standard and autoshift tranny (with the clutch pedal) by replacing the shifter (XY) with a normal shifter plate and by running the airline for the hi-lo range.
Other than that, the transmissions are THE SAME.
My truck is an autoshift with the clutch pedal. I think it's the best setup. The only time that's a pain is in stop-n-go traffic. But even that isn't too horrible since the Volvo has an easy to push/hold pedal.
I've had my CDL now for a little over 8 years. In that time, over half of my driving has been in an autoshift (Volvo & Freightliner) (with a short stint in an ultrashift). With all the miles I've put on an autoshift, I've had literally ONE breakdown related to the autoshift itself. One of the X-Y shifter motors was "sticking", causing it not to shift. I was able to get it into our shop by either riding the rumble strips along the road to vibrate it into working, or by tapping the motor itself lightly if I was stopped. Other than that, I've had one clutch need replacing, and that truck had a little over 800k miles on it at the time. I've also had the back half of one of the tranny's need rebuilding. That one had 850k miles on it and was in no way, shape or form related to the autoshift, but rather just from normal use. I'm still looking/thinking hard about buying a truck and I can guarantee that whatever I buy will do the shifting for me, but I will have control of the clutch pedal.
Here's a pic of an autoshift (with clutch pedal):
Here's a pic of an Eaton Ultrashift LST(no clutch pedal) (OTR tranny):
Here's a little info from Eaton's website about the Ultrashift:
Quote:
Fully Automated Heavy-Duty Transmissions (no clutch pedal) for On-Highway Fleet Applications
* Fully automatic operation using the industry proven, and industry-preferred Fuller® 10-speed “B”ratio transmission.
* Full automation (no clutch pedal) provides
o Greater driver comfort and less stress than manual shifting...increases satisfaction and safety
o Less time and expense to train new drivers
* The Fuller UltraShift LST “Multi-torque” automated transmissions provide additional torque in the top-two gears, 200 lb.ft. for the direct models and 100 lb.ft. for the overdrive model, improving efficiency and gradability in on-highway fleet applications.
o Specifically suited for on-highway applications with “gear fast, run slow” drivetrains.
* Designed for linehaul operations up to 80,000 lbs. [36,287 kg] and GCW at cruise speeds up to 65 mph [105 kph].
Driver is still in control
* "Manual" mode allows the driver to initiate and control shifts for flexibility during changing conditions or hold a gear as appropriate.
* "Low" mode boosts the rpm point at which downshifts occur to maximize engine braking.
Designed and built for reliability and easy service
* Electronic shift protection feature helps reduce the potential for drivetrain abuse…continuous electronic monitoring provides for quick, accurate diagnosis and repair.
* Modular components allow for easy service and replacement…often without removing the transmission.
* Automated clutch uses proven heavy-duty 15-1/2” two-plate design with an industry standard ceramic facing material for long service life.
* More than 6,000 factory-trained technicians at 2,000-plus dealer locations to support all Fuller automated products.
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Links:
http://www.roadranger.com/Roadranger...peed/index.htm
http://www.roadranger.com/Roadranger...tLST/index.htm
10 speed isn't enought for you? Try this one:
http://www.roadranger.com/Roadranger...peed/index.htm
New-To-Me Rig
