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Vibration under acceleration - Printable Version

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RE: Vibration under acceleration - tree98 - 08-11-2020

There's thousands of parameters in these programs, nobody has any idea what they might have changed in there. Everyone's experience can be different.


RE: Vibration under acceleration - cat6nz - 08-12-2020

(08-11-2020 )tree98 Wrote:  There's thousands of parameters in these programs, nobody has any idea what they might have changed in there. Everyone's experience can be different.
I was hopping someone went through this issue and after going to stock file issue got fixed, but thats fine maybe no one had this problem before, me myself will post in here for other ppl to see if its gonna fix it or not


RE: Vibration under acceleration - DVT873 - 08-12-2020

Probably a tune/injector problem BUT take a good hard look at you motor mounts. Have somebody rev it while your underneath (be careful) and watch for movement. Have had bad mounts cause some "interesting" vibration problems over the years.


RE: Vibration under acceleration - cat6nz - 08-30-2020

Hello everyone, its been a while since my last post but would like to do an update maybe might help someone latter on, i listen to the recommendations and tune up my 6nz back to factory 475hp file, unfortunately that did not help my vibration, some ppl mention engine mounts but i never paid attention because i did change them 3 months ago, guess what my issue was engine mounts, there are two plates one big one which goes on top of the mounts and the small one which goes under the cross member, in my case "mechanic" installed them wrong. Changed all mounts trans too and installed them on my own this time (took me 10 hours by the way) no more vibration engine runs smooth, still did not put under the load but i can tell problem is gone, some of you might lough at me but i swear i did change them 3 months ago and they looked new still, last tip you never tide the mounts too hard, hopefully this post help someone in the future, be safe all


RE: Vibration under acceleration - JimT - 08-30-2020

Thanks for the update.

Just goes to show that when troubleshooting an issue never take for granted or skip over something because you just replaced it or you recently checked it. Anything can break down at any time!


RE: Vibration under acceleration - cat6nz - 08-31-2020

(08-30-2020 )JimT Wrote:  Thanks for the update.

Just goes to show that when troubleshooting an issue never take for granted or skip over something because you just replaced it or you recently checked it. Anything can break down at any time!

Thats right, mechanics now days hold some blame as well, next step i was gonna drop trans ;) i consider myself lucky


RE: Vibration under acceleration - SquareOne - 08-31-2020

cat6nz ----> Appreciate the update...glad you let us know the outcome. Drives me nuts to read through pages of a thread only to find there is no conclusion...


Since we are on the motor mount topic now, what kind of miles are you guys getting out of them? I'm sure it's a subjective questions depending on abuse, what the truck typically hauls, and terrain/environment among others, but curious to know who's had them replaced and approx mileage.

I'm considering replacing mine when I shut down in Dec as part of a preventative maint item. They'll most likely have 550k-ish at that point. From what I remember, when Rawze and I were looking at the history of the old engine, it certainly looked abused!


RE: Vibration under acceleration - Waterloo - 08-31-2020

(08-31-2020 )SquareOne Wrote:  cat6nz ----> Appreciate the update...glad you let us know the outcome. Drives me nuts to read through pages of a thread only to find there is no conclusion...


Since we are on the motor mount topic now, what kind of miles are you guys getting out of them? I'm sure it's a subjective questions depending on abuse, what the truck typically hauls, and terrain/environment among others, but curious to know who's had them replaced and approx mileage.

I'm considering replacing mine when I shut down in Dec as part of a preventative maint item. They'll most likely have 550k-ish at that point. From what I remember, when Rawze and I were looking at the history of the old engine, it certainly looked abused!

Personally, I think that would be a smart move to PM those parts. I did my mounts on that first in frame of mine, 700,000 miles and glad I did. Don't forget the cab mounts too, I did those on the second in frame and it was beyond time. They were shot.

These new trucks are 500,000 miles throw away units, so anything you can do here and there is a good idea. My women always bitch at me for spending money on the truck, but it is better to replace these parts on my terms, not the truck's when it is sitting on the side of the road.

Thankfully I am to the point now that the front end is about all I have left, and I will start buying those parts in a few weeks, get ahead of that repair/failure, and hopefully catch it before it is time. I know I am there with just a hair over one million miles.

And ditto on the threads that start and never give an answer/conclusion...


RE: Vibration under acceleration - JimT - 08-31-2020

I can't comment on any recommended time to replace the motor mounts, but I can share my breakdown experience involving broken/missing motor mounts:

http://rawze.com/forums/showthread.php?tid=5682&pid=48875#pid48875
(01-11-2020 )JimT Wrote:  ...
Got my first load as an OO around the 25th of June. Heavy load of wooden spindles. Moved the truck to the side after being loaded, set the brakes, popped the clutch and bam, forgot to take it out of low gear first. Lots of bad words followed. Inspected the best I could but couldn't see anything broken. The next week or so I only hauled a few loads. Only weird thing I noticed was that the shifter would move a lot side to side when the engine was applying torque...

On my way home with another heavy load just after the 4th of July holiday and I messed up a shift on a steep hill about 5 miles from home. Next thing I know I'm getting low coolant and check engine alarms. Parked it before the temp got too high and ended up getting towed to a shop about 3 miles away. The torque caused the engine to twist just enough to break the plastic inlet elbow on the top of the radiator.

Come to find out that I broke the 2nd motor mount when I popped the clutch. According to the mechanic the other mount was completely missing and looked like it had been missing for a while. The only thing holding up the engine was the front mount. Yes, he replaced ALL the motor mounts along with the radiator during the repair. He also found that the remote lube hose for the clutch wasn't connected and ended up putting 2 tubes of grease into the clutch! It was much easier to operate after that.

When I bought the truck I had 2 different shops look at it, an annual DOT inspection and of course my ignorant self looked at it too. Of course I didn't know sh!t back then, so I can't just pass the buck and blame others for my ignorance.

Expensive lesson 3 weeks in to my new career. Still, that was almost $10k in total costs that should have been completely avoided, even after I screwed up with the clutch.
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