Drivetrian Vibration... Taking Bets....

[smitty3500]

Truck = 04. 5 3500 QC DRW. Nv5600. 68,000 miles. Two Peice Rear Shaft.



Replaced with SothBend Con-OFE. Was installed by Dodge Dealer Master Tech/Foreman. Clutch performs perfect.



After Install there is a seat of the pants vibration/hum at 76-77mph. Only at this speed. Not Clutch related, can travel at the speed and put in nuetral and let idle and the vibration is the exact same.



Started off thinking the normal, U-Joints. Replaced rear shaft with brand new Dodge part(still same). Check-measure shaft drive line angle(inspec). Replaced front shaft with brand new Dodge part(still same). Replaced front U-joints with new Dodge part(still same). Road force balanced all 6 tires(none were out of balance).



Vibration goes away if front shaft is taken off. Then had brand new Dodge Front shaft sent to driveline shop to check for straightness and balance. Came back perfect.



The dealer I take the truck to is a Great 5 Star dealer with one of the best techs in the State doing the work. He is not just throwing parts at the truck but replacing what the cause might be.



When clutch was done the T-Case was not removed from the 5600 so that would rule out and Vib coming from the T-Case(nothing changed). With everything New and replaced and wheels true and tires balanced... . What in the hell can be causing this vibration?



Taking Bets on what it is... .



T-Case, transmission, Front Diff/Axle?



Anyone had a minimal vibration like this?

 

[AMink]

Your cell phone rings on vibrate in your back pocket, but coincidentally only when you are going that speed? :-laf Sorry, no help here.

 

[smitty3500]

lol..... Cant be... . Phone is clipped on Visor... .



Just trying to hear any thoughts or "been there done that".....



Would rather not have axles/diff torn apart.

 

[AWise]

Was the CV joint checked when you inspected the front drive shaft?

 

[JWadford]

my truck does that with my front shaft in at 80-90 mph

 

[smitty3500]

80-90 mph I would not mind. 75ish is really the speed a travel on the highway. 10 over or so. Minor vibration but with hours of it non stop at that speed, one can imagine.

 

[raksasa]

The following is from the 2006 FSM regarding troubleshooting vibration... there might be a few things on here you haven't tried yet or some troubleshooting techniques you may use before throwing any more money at the problem. Good luck!​

PROPELLER SHAFT​

​

​

DIAGNOSIS AND TESTING​

PROPELLER SHAFT​

PROPELLER SHAFT VIBRATION
Out-of-round tires or wheels that are out of balance, will cause a low frequency vibration. ​

Driveline vibration can also be caused by loose or damaged engine mounts. Propeller shaft vibration increases with vehicle speed. A vibration that occurs at a specific speed range, is not usually caused by an out of balance propeller shaft. Defective universal joints or an incorrect propeller shaft angle are usually the cause of such a vibration. ​

FRONT AXLE - 9 1/4 AA​

GEAR NOISE​

Axle gear noise can be caused by insufficient lubricant, incorrect backlash, tooth contact, worn/damaged gears or the carrier housing not having the proper offset and squareness.
Gear noise usually happens at a specific speed range. The noise can also occur during a specific type of driving condition. These conditions are acceleration, deceleration, coast, or constant load. ​

When road testing, first warm-up the axle fluid by driving the vehicle at least 5 miles and then accelerate the vehicle to the speed range where the noise is the greatest. Shift out-of-gear and coast through the peak-noise range. If the noise stops or changes greatly check for:​

Insufficient lubricant.
Incorrect ring gear backlash.
Gear damage.

VIBRATION

Vibration at the front/rear of the vehicle is usually caused by:

Damaged drive shaft.

Missing drive shaft balance weight(s). ​

Worn or out of balance wheels.
Loose wheel lug nuts.
Worn U-joint(s).
Loose/broken springs.
Damaged axle shaft bearing(s).
Loose pinion gear nut.
Excessive pinion yoke run out.
Bent axle shaft(s).

Check for loose or damaged front end components or engine/transmission mounts. These components can contribute to what appears to be a vibration. Do not overlook engine accessories, brackets and drive belts.

 

[JCarlisle]

Since all of the components are turning at the same speed and if you are on a straight away try putting the truck in high 4 wheel drive and see if the Vibration goes away. I have seen a free spinning front drive shaft cause a vibration at speed on a large 6x6 truck it was like the Dodges (The Front End is Turning all of the Time) The Truck was Brand New and The Drive Shaft was balanced and checked for Straightness. We even went as far as replacing the Bearings in the front of the Transfer Case. Nothing Helped We finally resorted to getting on the Freeway and Engaging the Transfer Case to Send power to the otherwise freespinning Drive shaft and the vibration would go away, as I started to exit the Freeway I would shift out the Transfercase and drive through town without the Front wheels Engaged. I drove the truck for 2 years and did that daily without a problem.

I have noticed this phenomenon on other vehicals as well ( My Company Truck a 2006 F250 Ford) but most of them had locking hubs and they could be unlocked when they weren't needed. If the Vibrations Go away when in 4 wheel Drive re check all Front Drive shaft components for Tightness.

One last thing to check is the Pinion Bearings on the Front Diff as Chrysler Axles run more Bearing preload than other manufacturers they are more prone to failure.

I hope this helps

 

[smitty3500]

I will give that a try. I always hear people say you should not run 4x4 at that speed? Is that a myth or true? Will it hurt anything to run at 77mph for a few miles with 4x4?

 

[smitty3500]

Did a Very short run with 4WD High. Vibration is the same.

 

[JCarlisle]

Check the torque on the Front axle Yoke and the Transfer case yoke also. You will have to remove the Front driveshaft to do this. I have had a problem with both of these areas on trucks in the past. They usually leak but not always.

Make sure that the Driveline shop did a turning Balance on the Drive shaft