Hey guys. 2000 F350 7.3 Powerstroke, 230,000 miles, Getting a vibration in my drive line,not sure where its coming from. I think my trans (EAO A4LE). Only get it between 45 & 70. Fluids rite up there, Shifts great. Dont know if my u joints r junk. they seem fine but havent taken anything apart yet so i cant b sure. Could it b my diferentias? Kinda leaning on my trans. Any help would b great. Thanks.

 

If 230k, and no known history on drivetrain, I'd service the axle and remove the driveshaft and have the ujoints and center support bearing replaced... Checkout guzzle diesel site for axle fluid replacement

 

This is generally how I go about Vibration issues,
1. With the truck on a flat surface, install tire chocks, so that the truck can't roll forward or backwards. Put the truck in neutral, crawl under the truck. With your hands, grab the DL and move the DL back and forth, in front of and behind the Center support bearing, taking note of any play in the Ujoints, and up and down noting excessive play in the center support bearing and the slip yoke as well.
If they look ok, look for signs of damage to the the drive shafts or a missing DL weight here as well, IIRC they are tack welded to the drive shafts though.
2. Check tires for problems, bulges cut's separations & missing weights.
3. If everything checks out good to this point, I'll take my truck in and have my tires re-balanced. Loosing a tire weight will throw them off real quick, causing vibrations at varying speeds. Let the tire guy know your having vibration issues. He'll take note and check the tires for defects while re-balancing the tires. Also, ask him to show you the difference in all 4 tires, as far as how out of balance they were. Usually the place you buy your tires will do all of this for free.
If you do have to remove your DL for further repairs, U joints, Center bearing replacement etc, don't forget to mark them so that it goes back up in the same position you removed it.
.
Hopefully you can get it worked out.

 

Great advice as usual. Thank u for that. Ya got my but underneath and from what i see its the carrier bearing. I can move it up and down, pretty much play. im gonna start there, replace all three u joimts and see what happens. That bad boy has to get me to Colorado and back next month. Thanks again. Ill let u know how it turns out.

 

Sounds like a good plan on the DL repairs.

 

Did my u joints and carrier and it felt like a new truck. Even if they feel tight they may be froze up like one of mine

 

Use SPICER Ujoints so you don't have to do it again a year later, like I did.

 

02 F250 7.3 CC 2wd with 242k- I've replaced the ujoints and rotated and balanced tires as well. Only thing I haven't is my center joint. Mine seams to be more noticeable when turning left with acceleration and feels like thumping under the drivers seat. I do have some vibration around 45-50 mph but just chalked that up to a 3/4 ton super duty. Someone suggested my wheel bearings but had them checked and were ok.

I saw on another post a way to check for this on a flat surface with the wheels chocked. Rotate DL both in front and behind the center joint. Also, move up and down and check for play too. I'll have to try that and see.

 

I replaced all my U-Joints and my Center Joint, but still noticing something. An odd noise of sorts. I was hand-turning the front drive shaft last year, and thought I heard the same noise. Was thinking the front pinion bearing, which the front shaft connects through, into the differential? Doesn’t the front drive shaft still spin, when in 2 wheel drive?

 

Remember Rutt, if you haven't already, check the wheels for missing weights. Or better yet, get them rebalanced. You should be able to get this done for free by your local tire guy. It's cheap and it just takes this one more possibility off your list. The tire guys are pretty good at spotting a defective tire as well.

 

In 2 wheel drive the front drive shaft, and axle shafts are free when not engaged in 4X4. You can verify this by reaching underneath the truck and turning them by hand. Now, if you manually lock your hubs the axel shafts along with Ft drive shaft will be locked together and turn as you drive, but your transfer case will not be driving the 4X4 system until you lock the Tcase, with a turn of the Esof switch, or a pull of the Manual 4x4 Tcase Shifter, depending on which one you have.

 

On Edit: Rutt, The more I think about it, with what you described when turning, I would be very suspicious of a Unit bearing going out. It doesn't hurt to jack it up and inspect them both. You'll have to remove the rotors and caliper's to verify this. Also, while your in there, it's a good idea to regrease the unit bearings thru the ABS ports if your familiar with this process..

 

Go ahead and try spinning the front axles by hand when the truck is in 2WD and in Park as Countrycar suggested.

It's possible your hub is hanging up and that's the noise you're hearing. Hubs locked in or partially.

Also listen for any clicking noise when you turn it.