hi, I was pulling my trailer the other day.. I got on it and the rpm hit about 5000rpm. after I let off I had a slight miss at idle.

I pulled and changed plugs, and noticed that cylinder 3 the plug gaps were closed... its like I had valve interference, or rod stretch.

any ideas?
thanks
arlan

 

How does the truck run after the plug change?

 

runs great now...
I keep from going over 4k rpm though, which sucks...

 

I doubt you did any damage. If you kept it up there awhile maybe. I has an 04 Hemi, it was re geared for towing. Going thru mountains of the mid west. I would get it up to 4000.

 

Take it to high rpm again and see what happens. Never heard of rods stretching.