Poor drivability; 2011 Manual with 3.42 Gears

[schmalda]

RVTRKN,

Took truck to dealer today.

Verified the truck is not sutck in Regen and it has never performed a Regen; Tech noted as 'normal' for 11k miles. Currently "Count" is at 4000; needs to be at 25000 and have a high soot count to initate a Regen.



Also verified that my Truck has latest 'Driveability' flash.....



Dealer did find a code today; Air Conditioning Pressure Transducer was not within spec. it was replaced.



Continuing to work parallel path with Cummins Engineering; secured contact info for Cummins' Lead Chrysler Engineer. Will likely contact him next week.....

 

[AMink]

I don't know much about the newer trucks, just what I've read on here. Could you put the truck on a dyno and see if it is making the power it is supposed to? Or at least compare to a like truck?

 

[MChrist]

Maybe your truck is retaliating for being called "Cummings". Try calling it what it is, "Cummins" and it may start running right...

 

[EMAC2]

RVTRKN,

I'm tracking you w/the ‘stuck throttle’ workaround. I now do the same thing when near or at full throttle, I lighten up on the throttle for about 2 sec. just before clutching in then it doesn't overspeed. My truck does this all the time. The vehicle was flashed about a month ago but exhibited this “stuck throttle“ behavior since I took delivery in June.....



David

That's torque management. If you use an aftermarket tuner, that "issue" goes away..... The engine actually follows the throttle pedal... .

 

[AH64ID]

Never having had a regen in 11K miles is not normal. The people I know that have the 4th gen's had a regen about every 150-200 miles when the emissions gear was installed.

 

[Schrowang]

I'm wondering if you're keeping your RPM's up. On my 2010 w/ 6 speed manual, 4wd and 3. 42 diffies I start in 1st and wind it up to 2500 rpm. By the time I'm in 2nd it's drifted back to 1800 rpm and I find no lag or problem with it towing or bob tail. I'll wind it up to 2800 in 2nd and shift to 3rd at 2000.



If it's not the rpms then there's something wrong with the engine.

 

[MChrist]

If there has never been a regen, I would assume there must be significant restriction in th DPF. Perhaps there is a problem there...

 

[schmalda]

Schrowang,

Don't know if you had chance to look at the data sets I posted... . in my 0-60 mph run I shifted at 3200 rpm in each gear. This is not how I typically run the motor but I was going for max performance. In the linked data sets I show how the motor repeatedly will not produce full power in 3rd gear..... I agree something is wrong with the engine.



MChrist,

Thanks for the tip; I'll put the Regen question to Cummins Engineering.

 

[AABEN]

Yes, the sale is the bottom line. Very few salesman are informed about the product, just sell it!



We also don't have any info on the truck, what is it exactly? Is this the OP's first heavy duty diesel? Is he used to light weight pickups with gas motors and decent acceleration?



If the truck in question is sick with 3. 42's it will be sick with 3. 73's. He says it tows fine, just slow to accelerate loaded or empty. I considered all three of my Cummins powered trucks "sick" when they were stock. A few mods and night and day difference. I do understand the OP's truck is new and under warranty so mods are not an option.



Nick

When I go looking for a new truck I have 3 question I ask and if he can't tell me what I want to know I tell him he can not sell me any thing!!

 

[MChrist]

I looked up 0-60 times for a 2011 ram, Cummins, but with automatic and 3. 73 gears. According to Motor Trend, it will run 0-60 in 9. 9 with 2000 lbs in the bed!

Granted, the automatics are slightly quicker, but something is amiss. The fact that you get less power in third gear indicates it's not the DPF, but something in the computer. Your 0-60 times of 17 seconds are just plain sad, but not the cause of the rear gear.

 

[MChrist]

Here is a bone stock dually, 6 speed manual:


Check out this video on YouTube:

0-100mph 2011 Dodge Ram 3500 Mega Cab Dually Cummins W/G56 Manual. - YouTube


Looks like he gets to 60 in about 12. 5 seconds

 

[schmalda]

Thanks MChrist,

My worst recorded full throttle 0-60 mph acceleration empty is 14sec; subtract ~2. 5sec. for shifts to compare to an automatic and I'd likely be at 11. 5 sec.



Agree with you regarding gearing; it is not the root cause of the truck's drivability issue. I've resigned to stick w/the 3. 42 gears... . I have no trouble w/power when on highway at steady state... . pulls like a freight train.



To be clear my end is not to have a drag truck; I have other vehicles for that purpose. The 0-60 time is just a convenient standardized measure of performance that also happens to capture my truck's repeatable poor fueling/power behavior in 3rd gear.



Thanks,

David

 

[schmalda]

MChrist,

Just saw your YouTube post; good find... ... thanks!

My 0-60 times are better.



Driver started in 2nd (so do I w/o load), he had to shift into 5th to get to 60mph due to his lower gears; I'm at ~2700 RPM at 60 in 4th... . so less shifting = faster time



Note the persistent fueling and resultant rpm overshoot when the Driver shifts between 3rd/4th and 4th/5th. This didn't happen because he's still on the throttle; this is persistent fueling. My truck has the same behavior when ever shift between gears at full throttle. I understand from my Dealer's Lead Diesel Mechanic that this occurs on Autos too but is only noticeable if you throttle it hard from a standing start and then try to stop quick... . you almost can't because the engine is still over fueling. My guess is this delayed fuel down is built into the fuel map to reduce emissions.



Which leads me to a question; does anyone who has an aftermarket tuner see this persistent fueling behavior?

 

[RVTRKN]

schmalda, do you have any updates?

 

[RVTRKN]

Any updates?

 

[schmalda]

Update... ...

No progress made in solving my driveability problems with Chrysler Mid Model Year Manager at Cummins or my local Dodge Dealer; I've given up on both of these avenues.
Now starting research into aftermarket controllers.

Thanks,
David

 

[Wingate]

I would suggest thinking carefully about the idea of hiring a lawyer.



The window sticker indicates differential gearing.



?

Thats not always the case anymore... . I have looked at many 2011-2012 window stickers on Ram 2500 p/u that do NOT advertise gear ratio. I have come to realize thru trial and error that the Laramie Longhorns with diesel/auto/4wd if they are not advertised, they are more than likely a grocery getter 3:42...

 

[MChrist]

MChrist,
Just saw your YouTube post; good find... ... thanks!
My 0-60 times are better.

Driver started in 2nd (so do I w/o load), he had to shift into 5th to get to 60mph due to his lower gears; I'm at ~2700 RPM at 60 in 4th... . so less shifting = faster time

Note the persistent fueling and resultant rpm overshoot when the Driver shifts between 3rd/4th and 4th/5th. This didn't happen because he's still on the throttle; this is persistent fueling. My truck has the same behavior when ever shift between gears at full throttle. I understand from my Dealer's Lead Diesel Mechanic that this occurs on Autos too but is only noticeable if you throttle it hard from a standing start and then try to stop quick... . you almost can't because the engine is still over fueling. My guess is this delayed fuel down is built into the fuel map to reduce emissions.

Which leads me to a question; does anyone who has an aftermarket tuner see this persistent fueling behavior?

I must have missed this post from a while back. Yes, my automatic does the persistent fueling thing if I stab the throttle in park, and let off at 2,000. It will rev to redline and stay there for a second or two. Did this stock and still does it with Smarty.

 

[RVTRKN]

Update... ...



No progress made in solving my driveability problems with Chrysler Mid Model Year Manager at Cummins or my local Dodge Dealer; I've given up on both of these avenues.

Now starting research into aftermarket controllers.



Thanks,

David

If your going to do deletes, can you ask a question for me? Can the aftermarket programs work with the DPF still intact and operational, and then switch back to original OEM to run a regen when I want it to happen.

 

[AH64ID]

There are aftermarket tunes that keep the DPF intact, and regen as normal (without switching to stock). If you run a DPF delete tune you must delete the DPF.



I wouldn't add more than 40hp with the DPF installed.