FX4_GUY

Ok the truck vibrates at all speeds .. It also has a hum when shifted into drive or reverse.. Sort of whoomp noise coming from the rear of the truck , a little whine in the rear end arou 45-60 then gets quite.. So My wife got in the truck and shifted from reverse to neutral to drive a bunch of times while holding the brake , I looked under the truck but could not see the u joints move or twist... But I did the see the reaer differintial move up and down slightly I also heard the drivshaft clunck every time . Then I tokk off really fast after that and heard a few squeaks... I have narrowed everytrhing down to the U Joints or the rear end.. Or the Bridgestone duelar a/t 's that I just bought 6 months ago .. Sounds maybe like a seperated belt in the tire .. But the vibration get better and worse at different speeds , I do also feel a viberation when engaging drive but only for a few minutes >> WHEW DID I SAY ALL THAT<< The local shop wants 125.00 just too look at the truck..

Ckale

I think ive heard that before, im pretty sure its the u-joints but not positive

mawk

Have you physically gone under the truck and tugged on the drive shaft?

FX4_GUY

I did go under the truck and tugged at the driveshaft I tugged and Tugged but I could not get it to move.. However I did put some grease on it a while back to see if I could get it to stop . But the symptoms are all there .. Vibrations , a clunck going into reverse and a clunk going into drive .. It doesn't make sounds backing up though or while driving.. But when you are going abought 25mph its sort of a roaring sound like you are driving on a railroad track.. I thought it could possibly be a bad tire .. However the bridgestone duelar a/t tires only have 6000 miles on them.. Well what the heck I may just change out the U Joints today ,, Question though how heavy is the drive shaft in my 2003 FX4 ... I changed the U joints in my old 1993 F 150 xl along time ago and it wasn't too bad ..

FX4_GUY

I went outside and checked some more.. Now this part is strange , with the tires on the ground I can shake the drivers side rear tire from the top ( back and forth and it feels like the rim is loose at the lugs but it's not .. So I am figuring bearings... The people at Jackson Powertrain down the street didnt check it but said any rear end work starts at about 900.00 and goes up from there . That explains why they are never busy.. So It seems since I changed out the front Hub Bearings , shocks, Brakes and CV axles .. the truck actually rides worse.. Then the tires didnt help much either they ride worse than my pld mud tires that came on the truck when I bought it used about 16 months ago. So I mentioned to my w3ife this morning that I was going to be changing out my U joints today for fear of one being bad ,, She said it's all in my head ... The rear end whines at 45mph to 60 mph as well .. I did fix the grinding in the rearend on turns by changing out the gear oil and adding friction modifier but it only made the whining a little less loud.. I have the B6 rearend (3:73 ) Gears .. I guess I am going to go out and lift the back end of the truck just to see what is going to happen .. Maybe the wheel will fall off and I can prove to my wife that something is infact wrong

FX4_GUY

Ok anybody got any Idea's before I sale my truck ??? Just kidding... But dang I fix one thing after another and it just gets worse .. ABS light on all the time now , rear end bounces when brakeing , Probably need u joints, rearend whines.. and the Firestone shop down the street says everything looks fine and told me to stop slopping grease all over everything .. Man I have about had it .. And everytime I call the Firestone place about a problem now they say (((( If your so smart why don't you fix it yourself )))) Man if I had that attitude with my business I would probably go broke )

FX4_GUY

I may have found a problem... Look at the video up above..

FX4_GUY

Update .. I put the wheel back on and while it was in the air .. One rear wheel on the ground and the wheel in ? in the air. I started the truck and put it in reverse and as it spun around it made an awful grinding noise sound like it was rolling on gravel,, also i noticed the tire and wheel had a distinct wobble to it.. So leaking seal and bad bearing .. The rearend is a B6 373 LS... So how hard a job is it to change this out ??

Ckale

that sounds ugly...im not sure what to tell you. Replacing the rear axle shouldnt be terribly hard though, once you find one.

FX4_GUY

I am hopeing it is just a bearing and a seal...Autozone can order the axle they want 399.00 each.. As for the noise it is bad I know but I am thinking it is just a bearing .. I am not loseing much gear oil at all but there must be a leak somewhere..