Helping JimT out with an inframe ...

[JimT]

replaced it once already about 2 years ago and of course i'd replace it again when i do the rest of the driveline. I was being sarcastic when I said it didn't magically go away on it's own, in case that wasn't obvious in text. Also, I tend to call everything a "vibration" instead of a shake or shimmy, knock or bounce or whatever, sorry if that offends the technically minded. I actually think the problem is inside the transmission on the output side, but I can't rule out the diff either. It's definitely present regardless if I'm in gear or out, although it's slightly more noticeable in gear and accelerating or decelerating. Twice I've had motor mounts break that resulted in a shift of the engine and once I had to adjust the ride height up at least 1.5 inches, all of which could have put extra stress/wear on driveline components including the trans and diffs.

I'm not getting any noticeable wear patterns on any of my tires so that narrows it down a little. I've actually been wanting to do something with the transmission for a few years now but other things like the aftertreatment and the inframe kept getting bumped higher priority. However I think it's time to act before luck gives way to inevitability. I spend a few hours every day driving listening to only the engine, truck and road sounds, so a lot of what I'm hearing is subtle, but slowly getting progressively worse. I'm constantly questioning myself as to whether I'm being overly critical or trying to find something wrong when it isn't. So don't read too much into what I wrote above as it was just a synopsis of the past 18 months as opposed to troubleshooting questions.

man, if I wrote papers in high school like I write comments on this forum, I never would have flunked english classes due to missing writing assignments.