Truck Vibration

[LZimmerman]

Guys,

I have a 2005, quad cab, 6 speed with about 150K on it. it seems to vibrate more than I think it should. I have only had it for about 5000 miles, so I dont know the history on it. There were no mods done to it before I got it. at an idle it just seems to vibrate the seat more than I think it should. It gets about 25 mpg on the little computer screen, about 21-22 when I check it manually. It has plenty of power, no smoke to speak of, plenty of boost, starts relativley well. it does not start as quick as the old 12 valve, but I assume the Common rail system has to build higher fuel pressure before it will start? anyway, to lift the hood and look at the engine it is not shaking at all at an idle. My point is that I dont think it is an injector causing a miss that would cause it to vibrate. Motor mount? transmission mount? any one else have any suggestions?



thanks,

Larry

 

[Rotti54]

I had a bad vibration in my 04. 5 at highway speeds particularly around 65 to 70 mph. I had a bad front driveshaft and u joints. Dealership replaced it, and now it is much better.

 

[Cattechcolt]

First, try and find out if it is Drive train -or engine vibration, such as when driving, what speed does it occur? does it happen in every gear? what happens if you push in the clutch while at speed of vibration and let engine return to idle... does vibration continue or dissipate? this should help narrow down where your problem is coming from. Hope this helps

 

[goodguys75]

tires maybe?????

 

[GCroyle]

Which 6 Speed?

Larry,



2005 was a split year for the 6 speed transmission, early trucks got the cast iron NV5600 and later trucks got the all aluminum cased G56. If your reverse is LEFT and BACK = G56.



We need to know because there are different possible answers based on transmission.



Q. Do you feel the vibration with the truck stationary and just bring up the RPM? Or does it have to be moving to create the vibration?

 

[LZimmerman]

Gary,

Yes my reverse is over to the left and down, so a G56. just at an idle no movement in the truck, just setting there at an idle the vibration seems to seem worse than it should. bring it up to 1100 rpm then it gets better. again, if I lift the hood the engine is not vibrating overly excessive.



thanks

 

[GCroyle]

Larry,



I'll comment on the possible contribution of the flywheel to engine vibration, other TDR members can best speak for fuel delivery related and other possible sources.



If your truck still has the original clutch system, it uses a Dual Mass Flywheel, DMF. It has been observed and at disassembly it can be proven that the bushing that pilots the secondary F/W on the primary F/W can wear and allow the secondary which also includes the entire clutch to be moving around and not on center as it originally was designed to, I suspct that if you feel the vibration (truck stationary) and release (press) the clutch pedal and re-engage the clutch, it might even change the vibration sometimes.

 

[cerberusiam]

I'm with Gcroyle. The DMF is the source of many vibes and weird noises. It seems to be its nature. Can't rule out injectors but I would look at the clutch first if you have no other starting\running issues.



Yes the CR's take a bit more time to start due to the lectornics. Usually they should start on a count of 3 but the manuals can go to a 5 count before they fire. anymore than a 5 count and there is a problem somewhere.

 

[GCroyle]

Sorry I don't have a picture here at home to illustrate this bushing wear. Ford in the 7. 3L up to '97 used DMF's but their version used a BIG double row ball bearing to carry the secondary. The D-Max and G56 DMF are made by a different clutch company and rely on a thin wall bushing. If it wears uneven, one side keeps getting thinner and thinner, you get concentric runout of the secondary relative to the crank and it is a bunch of mass off center = vibration.

 

[sag2]

My vote is for a new clutch if it is only below about 1500 RPM.

 

[LZimmerman]

Great info guys. I have (in my mind) eliminated injectors. On the coldest day it will start by a count of 3 for sure. As soon as I get home I will check out to see if I can push the clutch and change the vibration. Stay tuned... ... ...