[TNdriver]

Hey y'all,

I am new to the forum. I recently purchased a 2012 1500 with 60k miles. It's got the 5.7 and four wheel drive.

The truck has a very noticeable lurch/vibration when rolling at low speeds in drive and reverse. It is perfectly smooth once the accelerator is applied.

The truck idles consistently at about 650 rpm.

I cleaned out the throttle body (it was not very dirty) and had no improvement.

Does anyone know what is causing this issue? My plan is to next replace the plugs.

 

[Thunderhorse]

Have the plugs ever been replaced? If not they're at 200% of their service life. I have not experienced any lurch myself

 

[TNdriver]

I replaced the plugs yesterday. It made no noticeable difference. The ones I pulled out were NGKs, not the OE Champions. They had normal wear and looked fine. I replaced them with OE Champions.

I did notice that one of the coil packs had been replaced with a non-OE AC Delco. Replacing that with an OE pack is my next step.

 

[Thunderhorse]

My OE plugs were NGKs. I think the coil pack is what I'd look at next; I'm not sure why there'd be a replacement coil on a truck with only 60,000 miles

 

[Submarine Jim]

Have the plugs ever been replaced? If not they're at 200% of their service life. I have not experienced any lurch myself

Actually, spark plugs are usually good for 100K on newer vehicles