2020 2500 Throttle Lag - Mornings / High Gear

[vwalla]

I have noticed significant throttle lag on my truck (2020 Ram Cummins Mega Cab 4x4). I have about 35K miles on it. The scenario happens in the mornings mainly and at around 45-50 mph (high gear). I did try the manual gear this morning and when it down shifted to 5th, the "rumbling" (feel like the truck is running out of gas) went away. Took it out of manual and it immediately came back.

I Installed the PedalMonster in hopes that it would remedy the lag. Although it does help in getting up and going, the vibration in the AM still is there. Seems like it may be transmission related, but it goes away after about 2-3 miles when everything is warmed up and does not do it at any other part of the day. Any help is much appreciated.

 

[crash68]

well hope it's not running on gas at all..lol
When was the last time both fuel filters were changed? Have you noticed a loss of coolant? or oil level change?

 

[vwalla]

LOL...right, meant diesel. The fuel filters were changed a few months ago and may be time to do it again. No loss in coolant and no oil level change.

Could the air filter come into play? When I got my first oil change, they popped a code when they changed the air filter by not securing it all the way down. It has since been fixed, but seems like everything started from there come to think of it.

 

[MADDOG]

Try your manual vs. full auto experiment again and watch the RPM readings when you do. I suspect you'll find the RPMs are higher in manual mode vs. full auto.

Basically, that means that in full auto it takes longer for the truck to get up to speed as you don't have as much torque to work with.

 

[vwalla]

Thanks, yes. I did do manual this morning and it stopped the rumbling, switched back to auto and it came back. Seems to only happen in the AM. Just doesn't seem like that is the way it supposed to ride, esp with 35K miles on it. I'm concerned it may be a transmission issue or torque converter issue (i'm no mechanic, so I'm just throwing stuff against the chalkboard).

 

[Dean2]

Take your mechanic for a ride and show him what it does because it will be very hard for him to replicate on his own. He should be able to track it down once he sees it happen. You are on warranty, might as well take advantage of it. May also be worth thinking about an extended OEM warranty if they can't figure it out.