Rear Axle Whine
Senior Member
Joined: Mar 2001
Posts: 865
Likes: 0
From: South Dakota
well, that tsb doesn't say it's normal, just says that is what the noise is. unfortunately on the internet you can't pull up the entire tsb. the rest of the tsb might specify doing something to the axle...the only way you'll know is to visit your local ford garage...
Senior Member
Joined: Mar 2001
Posts: 509
Likes: 0
From: Corona, CA
Driveline alignment, I just figured it out and solved the whining/vibrations/thunk from a start on my 2001 SCREW. I reset the pinion (rotated it upward with shims):
Here's how drivetrains should look...compare yours:
http://www.iedls.com/ptsetup.html
Here's how drivetrains should look...compare yours:
http://www.iedls.com/ptsetup.html
Senior Member
Joined: Mar 2001
Posts: 509
Likes: 0
From: Corona, CA
Troy,
It's a possibility that the pinion rotates slightly with a load, but I think most of the angle change is across the truck...you're reducing the angle of the driveshaft which angles down to the pinion. And...it doesn't take much of change for the noises and vibrations to go away (at normal speeds). I had a 5.1 degree angle on the rear u-joint. Every driveline specialists' write-ups I've seen states that a driveshaft u-joint should have no more than 3 degrees, but at least 1 degree to make sure the u-joint lubricant spreads and the roller bears wear evenly.
Buy an $8 protractor from Home Depot if you don't have one and check out the angles on the rear and front flanges and on the driveshaft. I need to have 5 degree shims on mine with only a 1.5 inch drop at all 4 corners! Does that tell you how much the stock pinion setting was off???????????????
You 4X's may even have a bigger angle on the rear u-joint than my 2X.
It's a possibility that the pinion rotates slightly with a load, but I think most of the angle change is across the truck...you're reducing the angle of the driveshaft which angles down to the pinion. And...it doesn't take much of change for the noises and vibrations to go away (at normal speeds). I had a 5.1 degree angle on the rear u-joint. Every driveline specialists' write-ups I've seen states that a driveshaft u-joint should have no more than 3 degrees, but at least 1 degree to make sure the u-joint lubricant spreads and the roller bears wear evenly.
Buy an $8 protractor from Home Depot if you don't have one and check out the angles on the rear and front flanges and on the driveshaft. I need to have 5 degree shims on mine with only a 1.5 inch drop at all 4 corners! Does that tell you how much the stock pinion setting was off???????????????
You 4X's may even have a bigger angle on the rear u-joint than my 2X.
Senior Member
Joined: Mar 2001
Posts: 509
Likes: 0
From: Corona, CA
Chrislee,
Actually, the sound was more a deep "grrrr-ing" than a higher tone "whining" and I noticed it at 40-45 mph. There was also a vibration with the sound at these speeds.
A few months ago, I had a whining sound from the transmission pump at lower speeds (from start up to about 25-30). I had 20,000 miles on it then and did not change the trans fluid yet since new. After changing the trans fluid the pump whine was gone.
Have you measured the angles on the flanges and driveshaft yet?
Also, you have 30,000 on your truck...still the same tires? At 55 mph, it might be your tires.
Kevin
Actually, the sound was more a deep "grrrr-ing" than a higher tone "whining" and I noticed it at 40-45 mph. There was also a vibration with the sound at these speeds.
A few months ago, I had a whining sound from the transmission pump at lower speeds (from start up to about 25-30). I had 20,000 miles on it then and did not change the trans fluid yet since new. After changing the trans fluid the pump whine was gone.
Have you measured the angles on the flanges and driveshaft yet?
Also, you have 30,000 on your truck...still the same tires? At 55 mph, it might be your tires.
Kevin
Last edited by Area 52; Aug 16, 2002 at 11:52 AM.