91 Vibration problems

[91Rustbucket]

The Blue Beast, formerly the rust bucket, has a new vibration problem.

91 Explorer 4.0 4WD

The problem: At any speed above 25ish I get a nice "VVVVUUURRRTTTT VVVVUUURRRTTT" vibration that I can both hear and feel. It goes in time with the vehicle speed, increasing almost to a steady humm at 60ish. I can feel it through the peddles and through the floor (I pulled the carpet and padding out awhile ago), and the passenger says that can feel it on their side as well.

What's changed: About 8 months ago I did a skyjacker suspension lift 2" and changed out the sway bars to a beefier option (changing back to stock soon I'm not fond of them). Then 3 weeks ago I installed 32" tires on steel wheels. About a week and a half later the vibration started.

What I've tried: I took the tires in and had them re-balanced (I knew the first place probably did a crap job) and they were wicked out of balance 2.75 on one tire, but that didn't change anything. I lubed up all of my fittings in the front, replaced the u-joints on the rear drive shaft, and checked my transmission fluid level (I'm getting desperate).

 

[jmdirk]

Is it more or less noticeable while coasting or under power? If there's a difference, good chance it's driveline related. Could also be related to wheel alignment. If the caster is out of spec it can cause vibration in the front end. The TTB is notoriously hard to align, especially when lifted. And with these you can't set camber independent of caster - it's kind of getting both as close to spec as possible. when you replaced the u-joints do you install the driveshaft in proper phase?

 

[roscoe 0202]

put the transmission in neutral and climb under and see if you can the flange on the transfer case and rear end up and down or sideways could be a bearing in either
roscoe

 

[91Rustbucket]

Is it more or less noticeable while coasting or under power? If there's a difference, good chance it's driveline related. Could also be related to wheel alignment. If the caster is out of spec it can cause vibration in the front end. The TTB is notoriously hard to align, especially when lifted. And with these you can't set camber independent of caster - it's kind of getting both as close to spec as possible. when you replaced the u-joints do you install the driveshaft in proper phase?

Thank you so much for replying, I've been running out of ideas. I would say that it's a little worse under coast vs. under power, but to be honest that could be just me noticing it because the engine has quieted. When you refer to proper phase do you mean putting it back in with the alignment marks? I am planning on having it re-aligned after I do ball joints and wheel bearings this weekend.

 

[jmdirk]

Based on that any your original post, I'd say it sounds driveline related. Somewhere between the transmission and the rear end. Drive shaft phase is that because these have a 2 piece drive shaft, if you separate the slip joint in the middle, you have to make sure that the ears on the yokes on either end are aligned when you put it back together. If you didn't take that apart, it's probably not that.

It does sound kind of like a U-joint, but you said you replaced those already. U joints will get progressively worse until it fails and you spit the driveshaft out from under the truck going doing the highway at 60 mph

The skyjacker lift in the back is what? Lift blocks? Shackles? Leafs? Did you have to undo the U bolts on the rear axle? Could be that they aren't tight enough and you're getting some axle wrap

 

[KurtECV]

Feeling it in the seat and pedals sounds like rear half of the truck. If you could feel It in the steering wheel it would most likely in the front and.

Have you checked and retorqued All your suspension componants after the lift?

 

[Albino 94LTD]

Also check pinion angle. 2" lift shouldn't change it but it may not have been correct to begin with. The pinion needs to be parallel to the output shaft of the transfer case. You can get leaf spring shims to adjust the angle.

Where in Washington?

 

[roscoe 0202]

pinion angle isn't as critical with double cardan joint
roscoe

 

[Albino 94LTD]

First gen's don't have double cardan rear drive shafts

 

[91Rustbucket]

Tearing apart the front end and I found my culprit, a bad wheel bearing. I was doing everything back to the ball joints. But I couldn't manage to get the passenger spindle axle out, I got stuck at the step where you knock it around with a hammer. While the driver's side came out alright, I gave up after 3 hours of knocking it around. Has anyone else had this problem?

 

[Albino 94LTD]

The passenger side inner shaft is held into the diff by a 'C' clip inside the diff. You have to pull the diff off the beam to get to it. Once it is removed there are several 'C' clip eliminator solutions. Just search for that on the forum.

Unless you're talking about the spindle bearing? I have destroyed several during the replacement process.

 

[91Rustbucket]

I'm talking about the outer bit that's held on by those 5 nuts, the Haynes says some persuasion with a rubber mallet will set it free, but I beat it on and off for 3 hours in all directions and got nowhere with it

 

[Albino 94LTD]

That's the spindle. Put a nut on the outer threaded part (so you don't bugger up the threads) and tap/hit on it from all angles. The spindle bearing on the back side might be seized to the axle stub shaft meaning you will have to try to pry out the outer axle stub shaft with the spindle. The Spindle has a very close tolerance fit. a lot of vehicle weight is on it.

 

[Albino 94LTD]

Where in Washington are you?

 

[91Rustbucket]

Southwest Coastal Washington, by the river. Maybe there is some pry trick I don't know without messing up the shaft seal, cause I pryed it quite a bit too.

 

[Albino 94LTD]

No place to pry. Thread the bearing nut on and tap it all the way around many revolutions. It won't move much. Heat might help a little.

'By the River' is that Long Beach/Ilwaco, West Port, Ocean Shores?

 

[Albino 94LTD]

If it still won't budge, put the rotor back on and bolt up a wheel to get more leverage.

 

[91Rustbucket]

Long beach, and thanks, I will have to try that wheel trick. I hadn't thought of that

 

[Albino 94LTD]

I know the aera well. I was born in Ilwaco. You may have to use something harder than a rubber mallet, thats why i suggest putting the bearing nut on.

 

[Albino 94LTD]

Wait, did you remove the ABS sensor and protection block? That may be holding it on. One of those little bolts is like 6.5MM. A weird size.