Rest In Peace, old friend, your work is finished.......
If you want on or off the DIESEL "KNOCK" LIST just FReepmail me........
This is a fairly HIGH VOLUME ping list on some days......
Posted on 11/17/2006 12:46:17 PM PST by Red Badger
Heavy-duty action is heating up in the pickup arena. Each of the Big Three is fielding a new or revised diesel engine, beefed up to grind it out in the marketplace.
All are powerful and capable, but Dodge believes its new 6.7-liter Cummins inline six-cylinder turbo-diesel, available in 2007 Dodge Ram 2500 and 3500 models in January, stacks up well against its formidable competitors. The engine also marks a big evolutionary step from the 5.9-liter turbo-diesel it replaces.
Displacement is a key advantage in the diesel battle, said Don Altermatt, Chrysler Group senior manager for diesel engine engineering, with the Cummins's 6.7 liters trumping the GM Duramax's 6.6 liters and Ford Power Stroke's 6.4 liters. The greater displacement is achieved by increasing bore and stroke. Cylinder bores are enlarged from 102mm to 107mm and the stroke increases from 120mm to 124mm.
Output is significantly boosted with the 6.7-liter's 350 horsepower at 3,013 rpm trumping the 5.9-liter's 325 at 2,900 rpm. More importantly, peak torque is upped from 610 ft.-lbs. at 1,600 rpm to 650 at 1,500 rpm. The lower the engineers can get the rpm torque the more low-end power the pickup has available to do work, he said.
"From 1,500 to 2,800 rpm it has a flat torque curve," said Dennis Hurst, Cummins executive engineer for midrange engines. "It produces more torque over a broader range than competitors."
Some competitors peak at higher low-engine rpm and then decay, Altermatt said. Bottom line for the serious trucker is that there's more torque available to launch, and to do it quickly.
Punctuating how far the Cummins diesel has evolved since it was first dropped in the 1989 Dodge Ram, idle torque is 10 percent higher than the peak torque of the original.
The 6.7-liter diesel comes with a new six-speed automatic, which is designed to handle torque demands beyond the engine's 650 lbs.-ft., and helps the engine deliver improved fuel economy and performance. Tow rating for the powertrain is 16,400 pounds, and payload capacity is 5,020 pounds.
"It will be a noticeable improvement in capability over the 5.9-liter at the same loads," Altermatt said.
Another component contributing to engine performance is a variable geometry turbocharger. It's a Cummins patent, Hurst said, and the first application of this technology on a Dodge pickup. Unlike the swinging-vane type others use, the VGT is a sliding-nozzle unit. It has the capability to precisely match boost pressure to optimize engine performance.
"With the capability of varying the turbine end we can get a more responsive turbo," Altermatt said. "And on the low end you can change the ratio of turbine-compressor speed. Then you can back it off and have the benefits of a larger standard turbo by opening up the turbine on the high end."
The VGT turbo also controls Exhaust Gas Recirculation flow rate and helps the engine achieve more torque at high altitude. The cooled EGR system also is responsible for reducing particulates and decreasing nitrogen oxide emissions. It allows the 6.7-liter to comply with all 50 states' 2007 heavy-duty emission standards.
The turbo's tendency to produce high-frequency noise is quelled via blade-path noise reduction. This is one of a long list of measures taken to reduce noise, vibration and harshness.
"Compared to the current 5.9, if you look at noise levels - sound-pressure levels, dBA of noise level - the overall noise level of the 6.7-liter engine is reduced by 3 dBA," Altermatt said. "That doesn't sound like much - except if you understand how sound is added, one source to another. That's like cutting the sound levels in half."
There is also "good noise," a throaty exhaust sound courtesy of an integrated exhaust-brake option, which is an integral part of the VGT. It comes with a switch to engage it and the software necessary to operate the brake in harmony with the transmission.
The exhaust brake is especially useful when pulling a heavy load, such as a big horse trailer or RV. It adds to braking efficiency and can reduce the amount of time a driver has to use the vehicle's brake.
"It's a deeper exhaust sound, not the irritating noise you hear with a Jake brake," Hurst said.
Cummins customers like the big-rig feel and are in tune with the company's heritage, he said. "This inline six fits with Cummins's Class A truck legacy." (Tim Spell is automotive editor for the Houston Chronicle Cars & trucks section.)
Rest In Peace, old friend, your work is finished.......
If you want on or off the DIESEL "KNOCK" LIST just FReepmail me........
This is a fairly HIGH VOLUME ping list on some days......
My wife and I used to have identical Dodge trucks.
One to drive, and one for parts.
I've got a 2002 Ram 1500, 52k, no problems.............
I have an '03 Ram 2500 with a Hemi. So far so good except for fuel economy. It will pass just about anything on the road except a gas station ;-)
One day, not too far into the distant future…all good automotive mechanics will be eating rice for wages.
I drove a friend's Ram 2500 4x4 diesel a while back from Ft. Walton Beach to Melbourne and back to pick up a trailer camper. It got about 18 mpg going down and 13 coming back. I was disappointed in the mpg. Maybe it was because it was a 4x4..............
1996 Ram 1500 extended cab, 5.2L Magnum V8, 154,000 miles. Looks like hell inside and out, but it's still running.
This is good news about the new diesel. The older Cummins were great engines, but they were LOUD.
}:-)4
I remember in my old neighborhood a man had an early 60's Dodge pickup, and the lettering on the hood said "D-D-D-G-E" or something similar (sorry, this was 35-odd years ago).
Apparently it was the result of a labor/management dispute, and the workers were being creative with the logos.
It is interesting that Dodge uses the Cummins Diesel, rather than the Mercedes truck Diesel unit.
The Mercedes engineering has been adapted to a lot of the Chrysler line already. Nobody hears "Mopar" any more.
Sounds like a great motor. Too bad its in a Dodge.
You say that like it's a bad thing.
I have a 2003 Cummins 2500 ram....it pulls a 12,000 boat no problemo...and I live in Colorado...the passes..no problem....and 14.9 miles per gallon to boot
I have a new 06 dodge Sprinter van with a Mercedes diesel. A man followed me to my campsite to ask if the Dodge had a cummins diesel. I told him it was a 5 cylinder mercedes. He nodded his head saying he thought I had the quietest cummins he had ever come across. He said he was a Dodge mechanic and was mystified by the obviously quiet engine.
I guess his dealership didn't sell Sprinters.
I looked at the Cummins, but the extra cost and my very short commute to work made it kind of impractical. I generally get about 8 mpg in town out of the Hemi, but my daily commute is less than 2 miles each way so it is not really even warmed up before I shut it back down. On long trips I can get up to about 14 mpg, 12 or so if I am towing the cannon.
My neighbor had an earlier version. It had torque all right. It destroyed the transmission at 8k miles.
Had a 1995 Dodge Cummins. Put 235,000 miles on it. No problems. Sold it and the man who bought it still thinks it runs great. He drives it to work everyday. It got 20 to 22 MPG empty. Never less than 12 pulling horse trailer.
My truck only had 175 HP and something like 330 pounds of torque.
model B Cummins is a great power plant for light to medium duty trucks. The B with an Allison is a great unit.
I wish I needed a new truck. The key word here is "needed".
Loud is a bad thing when you have a wifey who doesn't know she should appreciate those good things.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.