Chasing a highway vibration on my 96 Explorer

[1997XLTRollover]

Ok guys I'm kind of at a loss here and was just looking for some input. I don't want to just keep slinging parts at my truck to try to figure this out. So in a nut shell my truck shakes over 60 mph.

It feels like out of balance tires on the front but I don't think it is. I had brand new Goodyears on my stock wheels and now have a brand new set of 32's on Cragars and have the same shake. The steering wheel shakes ever so slightly but I think that's caused by whatever is shaking in the front end.

The shake feels like it's definitely in the front and I hear an ever so slight noise when turning left and right coming from the drivers front when in parking lots. I think it may be a wheel bearing that's getting old but I don't think that would cause a shake (correct me if I'm wrong) and the noise is very very quite not bad at all.

So far here's what I've done:

-New tires and wheels
-Front end alignment
-New sway bar endlinks and sway bar bushings
-New shocks
-New passenger side wheel bearing
-Checked for play in wheel bearings/ball joints and steering by pulling tire left/right/up/down feels tight.
-Ball joints all say Moog on them so I know they are not factory but I do not know when they were changed last
-Checked CV's and see no grease leaking, but I can move the axle shaft side to side (I think this play is normal, but again correct me if I'm wrong)
-Felt drive shafts for play and they also seem tight. I was thinking it could be the front drive shaft, but it feels like too heavy of a shake (it's not a vibration) to be a driveshaft I was going to pull this off and go for a drive but I feel like it's a waste of time.
-Swapped my rear drive shaft with a spare

 

[patmac6075]

Is it a brake rotor pulsing? Perhaps it's warped? Wouldn't explain the noise while turning....
Just a guess

 

[1997XLTRollover]

Is it a brake rotor pulsing? Perhaps it's warped? Wouldn't explain the noise while turning....
Just a guess

I honestly think the noise while turning is completely unrelated. But no I don't think it's the brakes, they're fairly new too and I don't really have a pulsing pedal when stopping. Good thought though. That's usually something overlooked by most.

 

[chefduane]

Does the vibration increase/decrease with speed increase/decrease? Or does it remain the same regardless of engine RPM? I had the same symptoms on my '98. Turned out to be a bad u-joint.

 

[1997XLTRollover]

Does the vibration increase/decrease with speed increase/decrease? Or does it remain the same regardless of engine RPM? I had the same symptoms on my '98. Turned out to be a bad u-joint.

The vibration changes with speed, I can rev the engine in park and have no vibrations. I had a feeling it was a u joint but can that really shake the truck that bad? It feels like a heavier shake more than a vibration.

The front drive shaft has been my thought the whole time but it just seems too heavy a shake to be the universals or drive shaft itself. Maybe I should bite the bullet and just pull the shaft too see if it goes away.

 

[chefduane]

Find a long stretch of open, flat, straight, highway and bring the vehicle up to the speed where the vibration is apparent. Then shift into Neutral (carefully) and coast. Does the vibration go away? Then rev the engine a bit. Does the vibration go away or stay then?
When coasting in N and revving, if the vibration stays, then its got to be engine related. If it goes away, then I'd think it is driveline related. This helped me diagnose my bad u-joint. Also, coasting with no power, tap the brakes a little. If you get a vibration then, you might have a bent rotor as suggested above.
And yes, a bad u-joint can shake like the dickens!! When I'd get to 60+ mph, the whole car shook like hell!

 

[1997XLTRollover]

Find a long stretch of open, flat, straight, highway and bring the vehicle up to the speed where the vibration is apparent. Then shift into Neutral (carefully) and coast. Does the vibration go away? Then rev the engine a bit. Does the vibration go away or stay then?
When coasting in N and revving, if the vibration stays, then its got to be engine related. If it goes away, then I'd think it is driveline related. This helped me diagnose my bad u-joint. Also, coasting with no power, tap the brakes a little. If you get a vibration then, you might have a bent rotor as suggested above.
And yes, a bad u-joint can shake like the dickens!! When I'd get to 60+ mph, the whole car shook like hell!

I'll give that a shot. I've tried getting on and letting off the gas to see if the vibration goes away but it doesn't seem to ever go away, seems very steady. I hope it's not engine related. I have only 2k miles on a brand new 306. The engine is very smooth in park though so I don't think it's engine related. I may try that test and then pull the drive shaft and go for a ride to see if it's the front shaft.

 

[masospaghetti]

The rear driveshaft on my 96 Explorer was bent every so slightly to cause a highway vibration, could not tell by looking at it, ended up replacing it with a junkyard one and the vibration went away completely. I suppose the same thing could happen with the front shaft although as you describe it, it sounds like a tire/wheel/rotor issue, not a high frequency driveshaft vibration.

My Honda had a similar problem which ended up being out of balance brake rotors if you can believe that. Wagner rotors. Claimed to be balanced on the box. Might be worth trying.

 

[1997XLTRollover]

The rear driveshaft on my 96 Explorer was bent every so slightly to cause a highway vibration, could not tell by looking at it, ended up replacing it with a junkyard one and the vibration went away completely. I suppose the same thing could happen with the front shaft although as you describe it, it sounds like a tire/wheel/rotor issue, not a high frequency driveshaft vibration.

My Honda had a similar problem which ended up being out of balance brake rotors if you can believe that. Wagner rotors. Claimed to be balanced on the box. Might be worth trying.

My rear shaft was bent which is why I replaced it, then I saw the next one I put on had the same kind of wobble so assumed it was normal. Maybe I happened to get another bad drive shaft on the rear? That would be my luck. If I put my truck up on stands and put it in drive the shaft hops as I'll call it. Not much but just a bit.

But yes it seems more like a wheel out of balance, not a driveshaft vibration. The frequency of the shake is not often enough and feels heavier because it almost shakes my truck side to side, not like something I would expect from a drive shaft. Seems like every tire rotation but who knows I've been wrong before.

 

[toypaseo]

If you want to try a re-balance, find a place on the link below that uses a Hunter Road Force Touch GSP9700.

When I purchased a pair of slightly used tires for my g/f's Xterra from Discount Tire on eBay, I had a local tire shop mount them. Had vibration issues, had them re-balance, still the same. I called Discount Tire, and they suggested going to that website, finding the closest one, and have them balance. They even offered to reimburse the fees. Went to a business that used one, did the re-balance, and no problems, even up to 90+ MPH.

http://www.gsp9700.com/search/findgsp9700.cfm

Maybe consider hubcentric rings for your wheels, if available.

 

[jamie3529gq]

i have had a bad front wheel bearing cause a shake. It was on a GMC Yukon, similar type bearing. Shook all the way from Iowa to West Virginia and back, good times. Made noise when turning as well. By the time i replaced it it was really really bad....

 

[1997XLTRollover]

Well I put the truck in neutral at 65 and the vibration is still there. It feels like a solid shake from the floor boards and not tire related, especially since my old stock wheels and tires had the same problem. I'm debating changing my wheel bearing for the hell of it but I'm going to start by pulling the front driveshaft to see if the shake goes away.

 

[chefduane]

Hmm. Unbalanced driveshaft maybe? Sometimes (but very rarely) a balance weight will dislodge from the driveshaft. ..be interested to hear what happens when dropping the front driveshaft.

 

[1997XLTRollover]

Hmm. Unbalanced driveshaft maybe? Sometimes (but very rarely) a balance weight will dislodge from the driveshaft. ..be interested to hear what happens when dropping the front driveshaft.

It's possible; that happened to my F-150 last year. It does feel like it's a solid shake from the center of the truck almost toward the front under my feet. If I had to guess I would say it's a screwed up front driveshaft based on where I feel like I'm feeling the vibration. But it's just a pretty heavy shake to come from such a small driveshaft.

The rear one just bugs me out because it literally hops, but maybe these things weren't machined the greatest because both of the ones I have are convex to some degree and hop when they spin. I suppose as long as they're balanced that shouldn't be a big issue.

Oh and remember this is on a 96, so I don't have that crappy ball and socket type design front shaft, my truck actually has the regular universals thank god.

 

[1997XLTRollover]

Ok well I just pulled the front shaft and the vibration is still there. I did notice that the transfer case connection moves in and out. I'm assuming this is normal but can someone confirm?

Side note my front shaft is a double cardon. Wooo! Why did Ford change from this to the garbage ball and socket design?

 

[gmanpaint]

A bent rear axle would give a good shake. does the vibrations increase with speed?

Easy test is to jack it up, place on stands, remove wheels, and let it idle in gear. Watch the calipers and rotors for out of round wobble.

Another simple test is to swap the front tires to the rear. This will help discover a broken belt in the tire. Go for a ride, and see if the vibration lessens after this.

Your stock wheels are both hub & lug centric. Changing to aftermarket wheels can affect the behavior as not all aftermarket wheels are hub centric. As Toypaseo mentioned, the rings help with this. Using the acorn lug nuts will help center the wheels. Just a fraction off, and they wobble, but the wobble increases with speed.

A loose hub nut can give a shake, but will also cause a bit of bumpsteer, and cause lane wandering.

Inside the Dble Cardon shaft is a joint that goes bad and makes a noise when bad. PITA to change out! You can get a little clunk out of it when bad. A "little" play in the front output on the case is normal I think.

The other item that pops into mind is the 5th shock. Some people say they get a wobble when they remove them or if they have worn out. Others say they don't notice a difference on or off. I think it just depends on the individual vehicle. The 5.0L has an additional support bracket from the axle that is intended to help with a wobble.

Just a couple things other then mentioned to check into. Good luck figuring it out.

 

[1997XLTRollover]

A bent rear axle would give a good shake. does the vibrations increase with speed?

Easy test is to jack it up, place on stands, remove wheels, and let it idle in gear. Watch the calipers and rotors for out of round wobble.

Another simple test is to swap the front tires to the rear. This will help discover a broken belt in the tire. Go for a ride, and see if the vibration lessens after this.

Your stock wheels are both hub & lug centric. Changing to aftermarket wheels can affect the behavior as not all aftermarket wheels are hub centric. As Toypaseo mentioned, the rings help with this. Using the acorn lug nuts will help center the wheels. Just a fraction off, and they wobble, but the wobble increases with speed.

A loose hub nut can give a shake, but will also cause a bit of bumpsteer, and cause lane wandering.

Inside the Dble Cardon shaft is a joint that goes bad and makes a noise when bad. PITA to change out! You can get a little clunk out of it when bad. A "little" play in the front output on the case is normal I think.

The other item that pops into mind is the 5th shock. Some people say they get a wobble when they remove them or if they have worn out. Others say they don't notice a difference on or off. I think it just depends on the individual vehicle. The 5.0L has an additional support bracket from the axle that is intended to help with a wobble.

Just a couple things other then mentioned to check into. Good luck figuring it out.

I would say around 60 mph is the worst and it smooths out just a bit at faster speeds. When I nail it from a stop I get a rumbling sound and vibration (I think because the front end lifts and starts to bind the CV's). I'm starting to think it's the front CV's because of this.

Good idea putting it up on stands and watching rotors. I'll have to give that a try too. I have Cragar soft 8's so they are lug centered and I don't have rings at the moment (I actually don't think the Soft 8's will accept the rings). I was going to swap the tires front to rear but I'm getting the same vibration I did with my stock wheels and tires so I feel like it's a waste of time but I'll do it when I pull them off to check rotors anyway.

I'll have to check my hub nuts because I did just do a wheel bearing 500 miles or so ago. Maybe it loosened up. I forget if I replaced the nut or not. I think I did but if there was not one in the kit I probably didn't bother (I know I know I'm not supposed to reuse it).

My 5th shock is removed because I lifted the truck. I can't honestly believe that small shock would prevent this kind of a shake. It feels like it's from the front of the truck around the front driveshaft/diff/cv's. I get a shake in the steering but I think that's the body of the truck shaking around from how bad the shake is not a steering wobble from tires or tie rods.

Either way thanks for taking the time to post, that's a lot of good suggestions I really do appreciate the help.

 

[chefduane]

I really would like to find out the resolution to this. Maybe a certified ASE Mechanic might have better knowledge of something, but I really can't figure that he might think of something that the folks here haven't thought of. I agree with your assessment of the 5th shock. I did mine just for the heck of it when I put on shocks, and if that little shock can damper as much vibration as it seems you're having then we'd be hearing about it all over the Forum.

And I have been guilty before of throwing parts at a problem before knowing the exact issue... sometimes it works, sometimes it doesn't.

 

[1997XLTRollover]

I really would like to find out the resolution to this. Maybe a certified ASE Mechanic might have better knowledge of something, but I really can't figure that he might think of something that the folks here haven't thought of. I agree with your assessment of the 5th shock. I did mine just for the heck of it when I put on shocks, and if that little shock can damper as much vibration as it seems you're having then we'd be hearing about it all over the Forum.

And I have been guilty before of throwing parts at a problem before knowing the exact issue... sometimes it works, sometimes it doesn't.

^Exactly what I want to try to avoid. We've all done it but as much as I love my truck and plan on keeping it for another 100k miles+ I don't want to just chuck money at a 20 year old truck. My truck's in decent shape but does have typical NJ rust. Also over and above the money, my time is precious and I don't want to spend it changing parts that don't need to be changed.

I really have a strong feeling about the CV's (specifically the driver side), it's just my gut feeling. The weird part though that's preventing me from just doing them, is that they don't have the typical clicking or clunking issues when turning that you normally get. The boots are also in good shape and there's zero grease leaking.



That all being said, how much side to side play is normal in a CV axle? If I grab the axle shaft, should I be able to move the axle at all side to side? My 99 before I sold it as well as my F-150 had minor side to side play as does my 96 (my 96 seems to have a little bit more play) so I'm assuming it's normal. But again I hate to assume, so when they're fresh are they supposed to be perfectly tight with zero play or is a mm or 2 normal movement?

 

[chefduane]

I recently did my hubs but not my CV's as they are not giving me any issues... yet. But I did have some lateral play in them. Not much, but some. About what you mentioned.
My research determined that is normal as long as the movement does not include front-to-back and/or up and down movement. That is, if they move side to side some you're ok. But if they get sloppy all around then that indicates problems ahead.