Ram beefs up chassis cab

THE Chrysler Group has launched 16 all new or significantly refreshed products in the second half of this year, including the all-new Ram 3500/4500/5500 chassis cabs.

Functionality improvements for upfitters include: four integrated upfitter switches and custom power distribution center; optional integrated trailer brake controller; single set PTO speed and torque converter lockup in PTO mode; standard 52 gallon fuel tank, industry standard 34 inch frame rail spacing.

The 3500 diesel front GAWR has been increased 300 pounds to 5,500 pounds. Dodge has increased the GVWR 500 pounds to 13,000. The Ram 3500 can now tow trailers with a maximum trailer weight of 18,750 pounds. The Aisin automatic transmission has an electronic range select for improved trailer towing.

Alternators have been upgraded for both diesel- and gas-powered models. Diesel engine alternators gain an extra 20 amps compared with 2010 models and are now rated at 180 amps. Alternator capacity for gasoline-powered models will be 160 amps for the 2011 models, compared with a 136-amp rating for previous models.

Dodge announced two changes for trucks powered by the Cummins 6.7-liter diesel — tandem PTO capability and the capability of using B-20 biodiesel.

From an electrical standpoint, the new chassis cab content includes:

  • Idle shutdown timer settable via service tool.

  • Hard wired remote start (for automatics only). “This is something that affects primarily aerial lifts,” said Dave Donnelly of the Commercial Vehicle Team. “It's a great improvement. We now offer a single wire under the hood so that once you enable the system, you can use this control line to go to a remote start and remote stop.”

  • Five programmable preset idle speeds for PTOs. “We had these in the past, but they had been at set speeds,” Donnelly said. “They are now programmable so five speeds can be set at anything between 900 and 2000 rpm. This is a very slick way where you can get one or two different speeds by alternating how you set them.”

  • New underhood connector for standard SAE J1939 messages (receive only). With them come eight signals: engine speed; vehicle speed; park brake applied; system voltage; brake switch status; clutch switch engaged; wait-to-start status; and coolant temperature.

  • Four upfitter switches located in the lower switch bank of the instrument panel. “All switches have 40-amp capability,” Donnelly reported. “One caveat: There is a total of 130 amps allowed, but any one of those switches is capable of driving 40 amps.” Switch connections are found under the hood in the connectors attached to the auxiliary PDC.

  • Improved upfitter wiring interface.

  • New upfitter module supplied by DGE Inc.

The auxiliary Power Distribution Center (PDC) is standard on all chassis cab models. It contains seven fuses: four for upfitter switches, one PTO (ATX)/spare (MTX), one 20-amp upfitter battery feed, and one five-amp mini fuse that allows Switches 1 and 2 to be changed from ignition feed to battery feed. The PDC houses six relays: four for upfitter switches, one PTO (ATX)/spare (MTX); and one that provides 20-amp upfitter ignition feed.

The new 2011 Aftermarket Upfitter Module was co-designed and developed by DGE Inc (www.dgeinc.com) and Ram Truck Engineering and is sold exclusively by DGE. The “receive only” module was bench- and vehicle-level tested. It connects directly into the vehicle's bus message system to provide outputs capable of driving relays. It has 25 outputs, including: vehicle speed; acc/run/start feed; oil pressure; ignition status; park brake applied; and transmission position.

“We've been trying to find a solution to allow you folks to get into a lot of the information on the vehicle,” Donnelly said. “The proprietary system has, up to this point, prevented you from getting engine speed, vehicle speed, ignition status, transmission signals, etc. The 25 outputs on this module are quite an improvement from previous years. I'm very jazzed about this and think it will afford you a lot of opportunity.”

Donnelly provided these body builder guide FAQs:

Q: Is there a circuit that remains powered when the vehicle is in accessory/ run/start ignition positions?

A: Yes. In the DGE module, there is a circuit that remains at 12 volts for all three ignition positions (preferred).

Q: Can one of the aux switches be used for a PTO switch?

A: Yes, sort of. The switch can be rewired from the bottom of the aux PDC to allow custom usage of the switches. The switch lighting feedback only tells you the switch has been depressed.

Q: Can I program the PTO to operate at two different idle speeds?

A: Yes. By utilizing the F425 circuit connection to the PTO switch, you can use the preset function of the vehicle to program up to five different (or all the same) idle speeds.

Q: Is there a signal that tells me if the engine is running?

A: Yes, it is part of the DGE module functionality.

Chris Borczon of the Commercial Vehicle Team provided these chassis FAQs:

Q: Where is the DEF Tank?

A: It is located under the cab and out of the way of any upfit.

Q: Do you have a DEF tank relocation kit?

A: No, you do not need one as it is already out of the way.

Q: How do you get the torque converter to lock up in PTO mode?

A: Any speed above 1200 rpm will lock the torque converter up.

Q: Can I idle my Cummins diesel for extended periods of time?

A: Cummins has confirmed that you can idle indefinitely.

Q: How do I request CAD data?

A: E-mail your request to the Ram Body Builder Guide Hotline. The Commercial Vehicle Team will send you the application forms which you should fill out and return. Once the completed application form is received, our legal group will review it. This takes approximately three weeks minimum. Once approved, you are added to the list of requesters. When your data is compiled, a CD will be mailed to you approximately one to two weeks later.

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