Weird Engine Sounds

[jgruberman]

I pulled up to a fast food drive through and was in Drive with my foot on the brake and the engine sounded a bit "clackier" than normal. Then with no movement or anything on my part, the sound shifted to a less clackier sound and a very soft rumble that I can feel in the brake pedal if I press down hard enough(to feel the vibrations).

Does anyone have any possible explanation for this that doesn't have bad news attached to it hopefully?

Edit: I also believe I heard and felt a rough shift... quite so more than normal. Maybe it's my imagination ...

P.s. I've always thought the shifting felt a little loose and slippy... maybe it's again, just my imagination

 

[Cummins12V98]

Could be regen.

Run Tow Haul and EB all the time you will like your shifting MUCH better!

 

[jgruberman]

Could be regen.

Run Tow Haul and EB all the time you will like your shifting MUCH better!

I will absolutely try that out next time I drive. This is the first Cummins, heavy duty, "adaptive" transmission I've ever owned, so I feel like I'm back in my teenage years when I started working on cars, knowing nothing about the engine or transmission and how they worked lol

@Cummins12V98 there won't be any issues with the engine or efficiency or transmission running both of those all the time?

 

[jgruberman]

Could be regen.

Run Tow Haul and EB all the time you will like your shifting MUCH better!

Another thing I've noticed... is that if my foot is off the gas and I'm coasting around 30-35mph, my RPM is near 1000 and has that chugging feeling... that seems low. Maybe a diesel thing?

 

[Newsa]

What year do you have? If it is a 2013-2014, you may need a flash if your engine sound changes during regen at idle????

 

[Cummins12V98]

I had zero issues with my 68rfe running th and Eb all the time. Trans was in proper gear all the time with firm shifts.

Per Dave Smith’s Head Service Adviser he said run the hell out of it when new. I did!

 

[jgruberman]

What year do you have? If it is a 2013-2014, you may need a flash if your engine sound changes during regen at idle????

It's a 2014. Does the louder clacking mean anything specific? For example, is it something I should be concerned about? Or nothing to worry about until a CEL comes on?

 

[jgruberman]

I had zero issues with my 68rfe running th and Eb all the time. Trans was in proper gear all the time with firm shifts.

Per Dave Smith’s Head Service Adviser he said run the hell out of it when new. I did!

What sort of mileage did you get? Also, did you have to turn it on each time or is there some trick for it to be on all the time?

Oh and do you use full or auto?

 

[Cummins12V98]

What sort of mileage did you get? Also, did you have to turn it on each time or is there some trick for it to be on all the time?

Oh and do you use full or auto?

Truck was my 11 HO Dually with 3.42’s. 65k at time of trade on current 15 with AISIN.

Yes I had to turn on at each start. It only had one EB setting.

I always run FULL EB and TH with my 15.

 

[Newsa]

It's a 2014. Does the louder clacking mean anything specific? For example, is it something I should be concerned about? Or nothing to worry about until a CEL comes on?

Nothing to worry about. They just had different programming for active regens at idle the first 2 years.

 

[jgruberman]

So on a more broad note... since I just bought the truck used... is there anything i should be keeping an eye/ear out for? Signs there's an underlying issue, etc?

 

[Newsa]

So on a more broad note... since I just bought the truck used... is there anything i should be keeping an eye/ear out for? Signs there's an underlying issue, etc?

Check to see if the rear fuel filter heater is recognized by the BCM. If they hook it up to witech and see what showd up as installed equipment, the BCM should show that a rear fuel filter heater is installed.

See attached TSB. I think all 2013's had this problem and some 2014's?

I don't see any problems to be worried about. This one just could be a temporary inconvenience.

See attached

 

[Ozymandias]

So on a more broad note... since I just bought the truck used... is there anything i should be keeping an eye/ear out for? Signs there's an underlying issue, etc?

Yes you should go to a dealer and let him check with the wiTECH that -all- your electronics is updated to the latest Revision.
This is important the newer the car is, those vehicle are like computers and smartphones, they are not finished after leaving the factory and need improvments over the lifetime.

 

[JR]

As to the noise you heard in the drivethru, be aware that when it is running your def injector makes a fairly substantial clacking noise. It is more noticeable when parked up against a wall where the sound reverberates.
It is not in the engine compartment so if you are absolutely sure that's where the noise was from then disregard. But sitting in a drive thru can be difficult pinpointing the exact location.

 

[jgruberman]

As to the noise you heard in the drivethru, be aware that when it is running your def injector makes a fairly substantial clacking noise. It is more noticeable when parked up against a wall where the sound reverberates.
It is not in the engine compartment so if you are absolutely sure that's where the noise was from then disregard. But sitting in a drive thru can be difficult pinpointing the exact location.

This may be it. I was up next to a wall and when the clacking changed, i felt a slight mechanical shift in the vibration in the truck like something had turned off. Definitely difficult to pinpoint the location though but this makes sense. When do the DEF injectors fire? Any specific times?

 

[NWatchel]

My 2014 sounds different everyday. Wind, snow, rain, day, night, Tuesday, Sunday, morning, night it seems everything causes something to change.