Vibration-Driveshaft?

toomanyfumes

toomanyfumes

Well-Known LVC Member
Joined
Jul 16, 2008
Messages
489
Reaction score
0
Location
Racine
I've had a vibration between 40-50 mph. Can't feel it in the wheel, feels like a drivetrain vibration. Thought it was the tires, but just had new ones installed and the vibration's still there. The Lincoln dealer put in a pinion seal over a year ago, and I think that's about when it started.

I thought I read somewhere the driveshaft has to be bolted up the way it was taken off? Would it be worthwhile to unbolt the driveshaft and rotate it a quarter turn at a time untill hopefully the vibration goes away?

I haven't heard of U-joints being a issue on these cars, it has about 57,000 miles on it.
 
Yep.. It's called indexing the drive-shaft.. It worth a try if that's were you think the vibration is coming from.. I can't see that being the problem because most of the time, when you index, you are replacing U-joints. I don't think it's required to keep orientation from shaft to flange. Your drive-shaft could be out of balance because of a dent or what-not and that could cause the vibration though.
 
toomanyfumes said:
I've had a vibration between 40-50 mph. Can't feel it in the wheel, feels like a drivetrain vibration. Thought it was the tires, but just had new ones installed and the vibration's still there. The Lincoln dealer put in a pinion seal over a year ago, and I think that's about when it started.

I thought I read somewhere the driveshaft has to be bolted up the way it was taken off? Would it be worthwhile to unbolt the driveshaft and rotate it a quarter turn at a time untill hopefully the vibration goes away?

I haven't heard of U-joints being a issue on these cars, it has about 57,000 miles on it.
Click to expand...

I have the same problem when my car hits 40mph. It annoys the hell out of me, but when I took it in they said they couldn't find anything wrong, but they road force balanced my tires or something like that thinking it would fix it. My Lincoln dealership moves to my side of town in 2 weeks so I think I'll wait & bring it in then & tell them I think it's the driveshaft.
 
I wounder if your drive-shafts are twisted? Or out of balance.. It doesn't take much to dent aluminum. Even the steel ones dent easy.

idk why these cars even have u-joints.. The rear pumpkin doesn't even move. If I remember right (haven't been under the LS in awhile) I think the front has a double-cardon joint that promotes 30 degrees of travel when regular joints are 15.. Whats the purpose? I guess just another thing to go wrong on the LS..
 
I get the vibration. its comes and goes. usually there.
Its a design flaw in the car (one of many lol).
Only thing i can suggest to minimize the vibration, is:
- Run good tires (i found Kumho W ecsta to be smooth),
- Get an alignment done, and
- Check your tire balance. Maybe the last person who balanced ur tires did a horrid job.
- Check to make sure bolts holing tire on, are tight.
- Check rims to see if they are bent.

Hope that helped =)
 
I don't get the vibration.. I did have it in the front but that was because of bad tires.. I replaced all the tires and now it's fine.. The two in the front were cupped..
 
I have brand new Eagle GT's. The vibration feels the same as it did with the tires I took off. I'm gonna get under it tomorrow and check out the driveshaft, bolts/u-joints, etc.
 
Yea, I didn't think your problem was tires.. To me, it sounds like the DS is out of balance. Check if the u-joints are worn too because that could cause it too. I was just stating to Lincoln_exe that I didn't have this problem and what not.. And since you have had different tires, chances are they aren't out of balance twice and put on wrong.. :shifty: I hope.. :D
 
I had to have a full rebuild of the axle at 54k, It had a grinding and howling coming from the back end, it sounded mainly like the right rear but turned out to be the ring and pinion
 
I was just reading that thread, hope it doesn't turn out to be anything like that. I do have a whining sound when I accelerate, but it's not very loud.
 
Mine was really speed dependent in the beginning you didnt hear it at all going slow but once you hit 35-40 it got louder till about 65-70 and then went away but it got worse the longer i drove... Good luck and i hope its something else... We have identical cars lets hope its not a curse
 
had to same issue and the diff went i and i had to replace it. the vibration issue bugs the hell out of me too i now have new rims and tires and a alignment and same issue one of the rotors is a little warped so im getting 4 new ones and replaced them all at the same time and if that doesnt work im calling the witch doctor lol..... and also checking the u joints.
 
Wow.


Driveshaft is steel, not aluminum.

It DOESN'T have U-joists at the ends, it has Guibos or otherwise know as flex couplers. Also what I would descibe as a pilot bushing in the middle to keep it centered. It has 6 bolts so it would be 1/3rd turns to index it.

It does have a u-joint and splined yoke in the middle by the center bearing. Some are a locked splined some are allowed to move free. Locked ones are likely a early design but I have not confirmed this.

You can hardly see the driveshaft at all from under the car as it has a full length heat shield covering it.

To replace the pinion seal they would have to disconnect the shaft so I would guess they messed something up. That or they messed up the pinion setting.
 
I've always read that on the LS, it was aluminum like a 1/4 of the car is..

Like I said, I haven't been under the LS in like 4 months and when I was, I really didn't look at the drive-shaft. I remember looking at it real quick and it looked like a double-cardon but I didn't really inspect it. Also, like you said, that heat shield was in the way so I couldn't really get a good glance.

You can go here for TSBs

I'll go on shopkey later and find more out to help toomanyfumes.

I still think it's out of balance or (since it doesn't have u-joints) out of measurement.
 
In the service manual, it says to keep all nuts and bolts matched to their locations on the shaft, as they are weighted differently so as to act as balancers. I've heard from others stating that they were not different at all on their machines, so I am only going by what the manual said. I did index mine to their original locations when I took the shaft off for support bearing replacement but visually, they did not appear to look any different from each other. If the manual is true, and they really did mix the bolts and nuts up, you're pretty much screwed, unless you can get it balanced on the car someplace.
 
milehighmikey said:
In the service manual, it says to keep all nuts and bolts matched to their locations on the shaft, as they are weighted differently so as to act as balancers. I've heard from others stating that they were not different at all on their machines, so I am only going by what the manual said. I did index mine to their original locations when I took the shaft off for support bearing replacement but visually, they did not appear to look any different from each other. If the manual is true, and they really did mix the bolts and nuts up, you're pretty much screwed, unless you can get it balanced on the car someplace.
Click to expand...

Good info Mikey. I too could not see differences in the bolts or nuts. Sucks cause with 6 bolts and 6 nuts at each attachment that makes for alot of combos.

The center bearing has colored hard washers, not sure what they are made of but I wondered if the were a certain thickness for the car. Also the center bearing mounting is slotted making me wonder if there was a certain way to set it tension wise. This would likely only be a facter on the shaft that has the locking nut in the middle. The other style move free in the middle so probably not a issue. Thats what led me to believe the locking style was a early then done away with model. The locking one also could be put together any way as the other has a double spline so it could be one assembled one way.

I would assume that one wouldn't seperate the shaft for the mentioned repair.
 
Sounds to me like the dealership didn't perform a driveshaft run out balance which is required any time the driveshaft has been removed. This is also why the nuts and any other parts are index marked when removed. I have been chasing this issue for some time now and had my driveshaft replaced on warranty 2 summers ago. The dealership didn't do a runout balance after changing the entire driveshaft and my vibration is worse. I had a local shop measure the deflection at both ends of the driveshaft with a dial indicater and it was out by 20 thousandth on one end and 7 thousandth on the other. With the car on a friends hoist, you could see the driveshaft deflection quite easily and I'm sure this is my problem. If you look in the workshop manual that owlman downloaded under noise vibration and harshness, it states that the driveshaft has to be balanced on the car and that a balance nut kit is available for this purpose. I puchased this kit, which contains several different size/color nuts, which are used to fine tune the balance of the driveshaft when it's in the car. I've gone through the same crap with the dealership of the tires being road force balanced and other stuff "they" thought it could be and it was all a waste of time. They didn't like it when after telling them numerous times to check the driveshaft, it actually was the problem. Anyway, if anyone has a vibration issue like this, I would get the deflection on your driveshaft checked. On mine, at about 70 mph, if you put your hand on the rearview mirror it felt like you were hanging onto an electric razor. Now with the new driveshaft, it's more noticeable at lower speeds. Still fighting with the dealership as they told me that this procedure is not part of the repair, to which I replied, if that be the case then why is it stated in the lincoln workshop manual?? Sorry for the long post, hope this helps...
 
You must log in or register to reply here.

Members online

No members online now.
Total: 425 (members: 0, guests: 425)
Back
Top