Ask the Engineer LIVE Chat - THIS IS THE PLACE!!

[Steve St.Laurent]

From ARedmon 11-18-2009 12:27 PM

I own an '05 with the G56 manual and have had no problems but I talk to a lot of other folks in campgrounds about diesel trucks and the one thing that always seems to come up about Dodge diesels is the automatic trannys that don't make it to 100,000 miles; some don't make it to 50,000! What's been done to the new HD automatics to alleviate this weakness?
AND, I might trade for a new 2010 with auto transmission (if I hear that the automatic transmissions have been improved) but one of the things I really liked about the '09 1500 was the center console with auto transmission shifter in it. I think this arrangement looks really good but for some reason this part of the interior isn't carried over to the HDs; why not?
And one last question. Why can't you offer lock-out hubs on your 4wd trucks? Especially with fuel mileage being so important these days. Also, it would be nice to use low range of the transfer case when easing a 5th Wheel camper into place without having to be in 4wd mode and feeling the resulting bind-up in the driveshaft/axles. That would be possible with lock-out hubs.

 

[Jayboy]

I'm reading all the questions... which are great... Where can I read the answers?



Jay

 

[wgood]

Can you clarify the GCWRs for the 2010 3500 DRW with regard to 2WD vs 4WD, 4. 10 vs 3. 73, G56 vs 68RFE, and why the differences?

Thanks.

Bill

 

[Steve St.Laurent]

From willde01 11-14-2009 10:29 AM

Manual regen

Would it be possible to allow the driver to force a manual regen when the dpf soot load reaches about 80% when it is convenient so the cycle could be completed. It would also be nice to allow the regen cycle to continue after you would stop the truck and turn the key off and allow the engine to continue to run until the cycle is complete then shut down the engine automatically, but allow it to be shut down in an emergency or if desired. It would also be nice if the driver could monitor the percent of dpf soot load on the overhead monitor.

 

[Spooled-up]

Ramengineer,



Can you explain why the Mega Cab is not offered with a long bed?



I think this truck would sell very well. There are many of us out there with families and stuff to tow. A wife, two kids and a 90 lb dog take up a lot of room. I need every inch of the Mega cab and also an 8' bed to tow and haul stuff in.

 

[Pat@BD]

Hello, with the switch to urea instead of the regeneration do you expect to see an increase in fuel economy?

 

[Steve St.Laurent]

From BSchwarzli 11-18-2009 09:19 AM

Quote:
Originally Posted by willde01 (Post 2101680)
It would also be nice if the driver could monitor the percent of dpf soot load on the overhead monitor.

VERY much agreed!

As it is obviously available in the system, why not make it avilable even if it is a user activated thing like the performance sub system in the SRT-8's (0-60 times, g meter, etc), that would be great!

Robert

 

[CumminsEngineers]

What is being done to increase the fuel mileage on these trucks. I know the trucks have had to get heavier to meet safety standards and have been overburdened with emissions and Dpf. But the big holdup for my new truck purchase is the awful economy of the new trucks. My 90 4wd got 22mpg, my wife's 01 4wd gets 17. 5 with the new fuel, and it just seems to keep getting worse. I bought these trucks for durability and efficiency... I don't need 650 lbs of torque or tire-shredding power.

Fuel mileage will vary due to truck configuration, duty cycle, cruise speeds and environmental conditions. From an engineering perspective, there is a inverse relationship between NOx emissions and fuel economy. To reduce NOx we need to lower combustion temperatures, which essentially lowers efficiency. We utilized new technology such as high pressure injection to regain some of this efficiency.



The emissions standards on the diesel truck market have been reduced significantly through the years-particularly the emissions standards changed significantly between MY1990 and MY2001. Despite the 50%+ reduction in NOx emissions that occurred in 1998, Cummins was able to meet this requirement and yet minimize the fuel economy degradation.

 

[CumminsEngineers]

cummins engineer I recently purchased an 09 what should the egt read at the 3 sample points be under normal and regen conditions thanks

Unfortunately, there is no simple answer to your question. The exhaust gas temperature varies widely depending on speed, load, operating condition, and regeneration state. Fortunately, the ECM monitors exhaust temperatures closely and will illuminate the MIL lamp if there is an issue.

 

[Pat@BD]

Hello, How do you expect the volumetric efficiency of the new engine to compare to the say older 2002 5. 9?

 

[Steve St.Laurent]

From dlmetzger 11-22-2009 09:02 AM

Fuel in Oil

My 2008 6. 7L was purchased new. Initially, used for short trips (~5 miles) and no load during the week, then loaded (9K) on weekend. Oil analysis showed 5 % fuel in oil (and climbing). I changed the vehicles use pattern (no short trips) and fuel level in oil dropped to 1-2%. I know this topic has been discussed before, but I'd like to cover it again.

Question 1: How much fuel can the engine oil tolerate and for how long and at what level?
Question 2: How does the fuel get in the oil? Does it slip past the rings at the end of the exhaust stroke while injecting fuel for the regeneration?
Question 3: If so, does this damage the rings?
Question 4: If not, is it the ERG? Please explain the mechanism for fuel in oil.

 

[RamEngineers]

Whet tests are used, and how exactly is the GCVW and GVW calculated?

GVWR is the curb weight plus the payload, GCWR is Curb weight + Max Trailer weight + 150 lbs allowance for the driver.

 

[RamEngineers]

I own an '05 with the G56 manual and have had no problems but I talk to a lot of other folks in campgrounds about diesel trucks and the one thing that always seems to come up about Dodge diesels is the automatic trannys that don't make it to 100,000 miles; some don't make it to 50,000! What's been done to the new HD automatics to alleviate this weakness?

AND, I might trade for a new 2010 with auto transmission (if I hear that the automatic transmissions have been improved) but one of the things I really liked about the '09 1500 was the center console with auto transmission shifter in it. I think this arrangement looks really good but for some reason this part of the interior isn't carried over to the HDs; why not?

And one last question. Why can't you offer lock-out hubs on your 4wd trucks? Especially with fuel mileage being so important these days. Also, it would be nice to use low range of the transfer case when easing a 5th Wheel camper into place without having to be in 4wd mode and feeling the resulting bind-up in the driveshaft/axles. That would be possible with lock-out hubs.

Hi,

Regarding your question on auto transmission durability, in 07MY an new diesel automatic transmission was designed and produced which offers superior durability (68RFE) versus the previous transmission (48RE and earlier 47RE). The 68RFE has been substantially upgraded and has proven field durability since 2007. For 10MY further enhancements were made to address issues found out beyond 150K miles. Failures are rare with the 68RFE since launched in 2007 and have provided substantially improved customer satisfaction with the 6 available forward gears and steep 4. 44:1 reverse ratio. We know of several customers with over 300K miles on them and still running strong.

 

[Steve St.Laurent]

From Super Briar 11-20-2009 09:04 AM

Could you give some info on just what is contained and or different with the Severe Duty Fuel Filtration Kit, for the 2010 6. 7L Dodge Trucks?

Does it have a fuel heater? If so does the heater have an on/off switch or is controlled by a thermostat?

Is this an option on the 2010 trucks or is it going to replace the standard fuel filter that was used on earlier 6. 7 trucks?

Can this kit be retrofitted to earlier 6. 7 trucks?

Thank you,
Wayne

 

[RamEngineers]

From ARedmon 11-18-2009 12:27 PM

I own an '05 with the G56 manual and have had no problems but I talk to a lot of other folks in campgrounds about diesel trucks and the one thing that always seems to come up about Dodge diesels is the automatic trannys that don't make it to 100,000 miles; some don't make it to 50,000! What's been done to the new HD automatics to alleviate this weakness?
AND, I might trade for a new 2010 with auto transmission (if I hear that the automatic transmissions have been improved) but one of the things I really liked about the '09 1500 was the center console with auto transmission shifter in it. I think this arrangement looks really good but for some reason this part of the interior isn't carried over to the HDs; why not?
And one last question. Why can't you offer lock-out hubs on your 4wd trucks? Especially with fuel mileage being so important these days. Also, it would be nice to use low range of the transfer case when easing a 5th Wheel camper into place without having to be in 4wd mode and feeling the resulting bind-up in the driveshaft/axles. That would be possible with lock-out hubs.

Hi,
Regarding your question on auto transmission durability, in 07MY an new diesel automatic transmission was designed and produced which offers superior durability (68RFE) versus the previous transmission (48RE and earlier 47RE). The 68RFE has been substantially upgraded and has proven field durability since 2007. For 10MY further enhancements were made to address issues found out beyond 150K miles. Failures are rare with the 68RFE since launched in 2007 and have provided substantially improved customer satisfaction with the 6 available forward gears and steep 4. 44:1 reverse ratio. We know of several customers with over 300K miles on them and still running strong.

 

[RamEngineers]

I currently live overseas. The local dealers are saying there is no Dodge with Cummins available (only with a Hemi), perhaps due to us not having low sulfur fuel? Is there an export version available or can a US version be modified so that I can import one?

We are working on a program that would accept high sulfur diesel. However, I do not have specific timing for that at this time. We can get back with you on that information.

 

[DodgeWarlock]

3.07 gear

Ram Engineers Is there any hope for the return of the 3. 07 gear ratio or something similar? Perhaps a double overdrive or 2-speed rear with a load sensor to kick out under hauling conditions?

 

[47Ford - 1.5ton]

3/4-1 Ton trickle effect into 1/2ton.... Head Design?

Hey guys,



Few questions so here it goes.



Curious if any thought or discussions have been thrown across the table into utilizing the 1/2 ton Ram truck platform in junction with a CR smaller displacement diesel. Much like your current on-road platforms similiar to the old 4BT or the current 4. 5L CR motors, I was curious why... or consequently why not in regards to utilizing such a durable and fuel efficient powerplant in a 1/2ton isn't being addressed yet. I noticed Ford at one time had a 4. 5L Powerstroke that was going to see the light of day in an F150... but it was then cancelled due to budget perhaps... . has this idea met the same fate?



Long story short, I know there would have to be some extensive work done in regards to fuel delivery and burn cycle to maximize efficiency and lower emissions to CAFE standards... but I would assume most of the R & D from the motors lower end and turbo managment would already be complete. Head design and after-turbo systems would need to be ironed out.





It might be a shot in the dark... . but I currently have a Cummins 4BT 8V in a 1947 Ford 1. 5 Ton DRW and its fuel mileage exceeds my 2005 1/2ton, and also the Cummins outperforms from a towing standpoint as well.





Also any thought given into head design and runners for better top end design in its current CR platform?





~Mike K

Green Bay, WI



University of Minnesota

Institute of Technology

Mechanical and Jet Turbine Engineering

BSME Graduate of 2006

 

[dkconnor]

I think the integrated turbo exhaust brake is a great feature of the Cummins Diesel. Would it work on Pre-MY07 engines?

 

[Steve St.Laurent]

From RKohn 11-12-2009 09:46 AM



Hi Guys.



Thanks for all of the improvements that you’ve made to our trucks over the years. It’s great to see you seeking owner input, because now we're all going to be looking forward to many more great ideas. (Maybe if the bean counters would let you actually build them the way that you want to, we'd even see a truck that holds up as well as the engine. )



Why does Dodge continue to gear for these trucks for 55mph? Many of us spend the bulk of our time on the highway and 2100rpm @ 70mph…. just doesn't cut it, for either noise or MPG. We shouldn't have to spend thousands of extra dollars to put an aftermarket overdrive unit on a new truck when you could be offering an optional 3. 07 gear ratio to get it down around 1600rpm where it belongs (It's not like we won't have enough low end torque. ).



For all of the Go Green hype, why aren't you guys getting more behind biodiesel and working towards using higher percentages? I'd love to buy another new truck, but until you have solutions for some of the biodiesel issues that we've heard about, like oil dilution caused by the DPF regeneration... . I'm sticking with my 03.



Regards,



Rick