Engine Shaking, RPM Based

[Mad Maxx]

I've Noticed Lately that my Engine seems kinda "Loose".

Whether it's Warmed Up or Cold, if I am Parked, and Rev to 1100 RPM's and Hold it there, the Engine will Shake enough to make the Cab Shake as well.

It's not Violent, or anything Crazy, it's just enough that if you're Sitting in the Cab, you can Feel it Wiggling / Shaking.

It'll go away if I Raise the RPM's, but it'll come back around 1800 RPM's.

I think this has something to do with a Weird Low Speed Shift I get as well. It Feels almost as if the Tranny is trying to Shift too Slow or Soft, and kinda "Tapers" itself into the Next Gear, rather than a Quick Clean Shift.

You think it could be a Torn Motor Mount?

Should I Order Up the M/A Motor Mounts?

 

[Unit453]

Does it do it all the time?


Mine's done it maybe 3 times in 2 years. I'll be sitting at a light and it'll feel like its got a lope to it. It isn't super noticeable either though.

 

[Mad Maxx]

Well it's RPM Based, so whenever the RPM's are in the Spot, it does it.

...and not that I think of it, it does it while I Drive too.

Almost like something on the Engine is Out of Balance. It has that kind of Shake or "Yank" to it.

 

[BoostN]

Those motor mounts will be OVERKILL for you IMO...

If your mount is broke, theres a fix by running a bolt through it.

 

[Mad Maxx]

I dunno, but there is def. something up somewhere.

I don't get any Bangs or Clunks like you would from a Bad Mount.

 

[SfcJones]

most newer style mounts have keepers to keep the engine from rocking if the mount is broken, however you could feel this vibration if it was broke. jacking up the motor will not tell if it broke or not....As earlier stated: MA Mounts are way overkill but if you have a hot tune then you shouldn't never worry about mounts again.

 

[Mad Maxx]

Yea, I'm always Running on my Hot Tune.

So maybe I should just get the M/A Mounts?

 

[CtChevy427]

Yea, I'm always Running on my Hot Tune.

So maybe I should just get the M/A Mounts?

James, save your cash and run the bolt through the mounts as Jeff mentioned. There is a truck on Pat's site making a ton of power and that is all that is being used.

 

[Mad Maxx]

Is there a Writeup on how to do it?

 

[CtChevy427]

Is there a Writeup on how to do it?

Can you get on Duramax Diesels?

http://duramaxdiesels.com/forum/showthread.php?t=2976

 

[dmaxfireman]

I did it on my motor when i built it...

pretty much to remove the mount. support engine. remove 4 bolts on the block 3 on the chassis. drill a 9/16" hole through the center of the mount. make sure you go through the center of the rubber part. put a 1/2" bolt through and put a nut on the back. once the nut is run up go another turn on the nut then grind the bolt down flush to the nut and put a tack weld on the nut so it will not back off. reinstall the mount and proceed to the other side.


kyle

 

[btfarm]

Or use a locknut.

 

[RI Chevy Silveradoman]

Yea, I'm always Running on my Hot Tune.

So maybe I should just get the M/A Mounts?

Try and go back to stock tune and check and see if the vibration or shake is still there. I seriously doubt it is the motor mount.

 

[Mad Maxx]

Try and go back to stock tune and check and see if the vibration or shake is still there. I seriously doubt it is the motor mount.

That's a good Idea. I didn't even Think of that. :thumbsup:

 

[saratoga]

I would think you'd really have to beat on it to bust a motor mount unless you're at the drag strip every weekend doing boosted launches.

The engine is so heavy that anything other than a perfectly smooth idle like an odd lope or misfire (for lack of a better term) shakes the entire truck. Think of how hard it shakes when you just turn off the key.

 

[Mad Maxx]

Well, there is no more Drag Strip out here anymore...and I've never done a Boosted Launch, so....

 

[83GMCK2500]

Did you try a stock tune? I have an OB-NOXIOUS vibration in my truck at almost exactly 35 MPH & 1,100 RPM or so...not sure on RPM at the moment, but that is close.