Mysterious Whining noise

[ftegarden]

My 2005, 2500 with G56 manual and 96000 miles developed a whining noise today. The specifics are: 55 to 58mph with 1800 to 1900 rpm in 6th or 2350rpm @ approximately 22mph in 3rd. This is only during "cruise" power and goes away while accel/decel. At 55 to 58 mph with clutch in, the noise goes away. At the 1800 to 1900 rpm in 5th there is no noise. It is a fairly high pitched whine. The ambient temperature is about 15 to 20F buty with engine well warmed up and after about 20 miles of travel. I had the tensioner and belt, trans and differential oil changed at 78,000 miles.



Any solutions or directions I should go in?



Thanks for the help!

 

[AlaskanCummins]

Funny you should post this as I have something very similar. :-laf



About 2. 5 months ago, my truck started to make a high pitched whine from 35-40 MPH. No other speed ranges. Push clutch in, whine stays. It seems to go away if I give her some fuel - most of the time.



Because it's only during a certain RPM range (same speed range equating to RPM of driveshaft, rear end, etc... ) I think it's a harmonic issue.



It does this regardless of being in 4x4 or not. So, the front end is eliminated. Only other items spinning are obviously the rear end, t-case, transmission and drive shaft.



I'm thinking the culprit is the rear two piece drive shaft. I had it re-built when I was in Denver this past May, so I don't think it could be u-joints. I'm going to try dropping the center bearing and re-bolting it to see if that makes it go away.



Something else - it does it more the colder the ambient temperature is. When it was in the 30-50* F range, it'd only whine until I drove about 3 or so miles. When it's sub-zero (like the last week here) it'd whine the whole day if I was in that 35-40 MPH range.



I'm going to try the "drop" trick with the center bearing tomorrow. I'll keep you updated.

 

[ftegarden]

Whinning Noise

AlaskanCummins

I'm going to be able to be under the truck today while having brakes repaired so I will check and perhaps 'drop" the center bearing like you suggest. Nothing ventured, nothing gained.



Thanks,

 

[rscurtis]

Another thing you could do is remove the rear section of the drivehsaft and run the truck standing still. If you still have the noise, that eliminates the front and rear axles, and you can locate the noise without the danger of a spinning driveshaft and wheels.



If you don't have noise at that point, engage the 4wd and drive the truck on the front axle and see what happens. If you still don't have the noise, that would point to something in the rear axle.

 

[gathomas]

Guys, just my . 02s, you might want to investigate Front Wheel Bearings... Now I realize your trucks are most likely 4x4s...
Mine is 2004 3500 Dually 2wd at 92,000 miles I thought the planetary gears were going in the Trans, call it what you want, whining, Growling, etc... it was loud... long story short... .
Bad Front Wheel Bearings... . worse than that... . $480. 00 ea dealer price... . worse yet... made in china... . lasted about 4000 miles.

Three sets of WB's later... . I installed "Timken" USA made

Oh, did I mention they are "Sealed" units. Good luck!!

 

[tbeddow]

Differential whine

I have a 2004. 5 3500 with 6 speed. I was living in Wyoming and had a bad whine in differential when real cold until truck warmed up. I took it to dealer and they diagnosed it as bad pinion shaft bearings. Repair cost $1200. 00 and I still heard it intermittentially. I have moved to Tennessee where it is warmer and have not heard it. I know it drives you crazy, it did me, but I believe it is the nature of the beast and I wasted $1200. 00.

 

[ColemanR]

I had a whine that I had a hard time finding I could tell it was up front was always at speed fan hub came a part about 1500 miles later if you take the tention loose give the fan a shake mite be worth while. Randy

 

[06SLTcs]

Timkens are the only WB to buy, I watched a spidertrax video comparing timkens to chinese ones, and new the overseas were out of lateral spec. Even desert raced timkens were still better.

 

[BGlidewell]

pinion gear. . ?