vibration is driving me nuts!

[essam]

Hi everyone,

I've been suffering this stupid vibration for a month now and it is really driving me nuts. I've read many posts on this but nothing seems to match the symptoms I'm having. anyhow, the truck is stock Ex 03 XLT with 195000 KM on it, it is exhibiting slight vibration with a hum at speed of 90Kmph up to 92 or 93 only then disappears. The vibration is felt on the floor, driver side only. now, i shifted to the passenger seat while someone was driving and felt the floor vibration at 60kmph then it disappeared. another symptom is accelerator pedal vibration at both 60 and 90. the steering feels a little bit vibrating but this has been there a while now (a year or so) and it feels the same at all speeds. front hubs are 35000 km old, front drive shaft is less than two years old, front half shafts were removed and lubricated last weeks, their boots are well sealed. at the same time with half shafts, i changed the four tires with the stock size (I'm using firestone 245/65/R17) with no improvement to the vibration. rear U-Joint sounds solid, no play in the rear drive shaft. one more thing, at speed of 90 i can hear the hum only in the driver seat and no were else, and recently (a day or two) started to hear a very slight rattle on the dash at 60 and 90.
i know I'm a bit sensitive to noise and all abnormal symptoms with this car, but it is really irritating especially it happens at the cruise speed on my way home daily.

does this sound familiar to any one? or can some one shed some light on how to proceed with the inspection?

thanks in advance!

 

[essam]

anyone??

 

[pet575]

I'd look at the front wheel bearings or the vehicle being out of alignment. Alignment is cheaper.

 

[sethmorgan]

Check the position of the roof rack cross bars, if you have them. Read post #6 here: http://www.explorerforum.com/forums/showthread.php?t=316701.

 

[essam]

I'd look at the front wheel bearings or the vehicle being out of alignment. Alignment is cheaper.

\

thanks for the response pet575, i think I'll go for alignment at the local dealer once the service is due. as for bearing, there's no play in the wheel when i shake it, is there any other way to check for a bad bearing??

 

[essam]

Check the position of the roof rack cross bars, if you have them. Read post #6 here: http://www.explorerforum.com/forums/showthread.php?t=316701.

thanks as well sethmorgan, that's kinda weird! i do have the roof rack and I've never moved them. however, any ideas about the factory position for them?

 

[sethmorgan]

On mine you could see where they were positioned originally. I had moved them rearward to accomodate a roof basket. I've since taken them completely off and have just the rails that run parallel with the direction of travel.

 

[essam]

I checked the roof rack rails, they are in the factory positions (as you said, it is obvious on the rails). there was a loose fastener on one on them, i tightened it but the vibration is still there. moving to next item to check

 

[sethmorgan]

Check all the rims for runout. You can see any abnormalities in the rear wheels by raising the rear and putting the truck in drive. It will spin them fast enough to notice anything out of round or bent.

Here's a long shot but a member on here posted about the rear diff mounting bushings (called isolators) he replaced that cured a vibration. I couldn't find that specific thread, but here's one with the part numbers: http://www.explorerforum.com/forums/showthread.php?t=192619.

I actually had one missing from a R&R done to mine: http://www.explorerforum.com/forums/showthread.php?t=325374

 

[essam]

I have the automatic 4WD, i think I'll have to have the four wheels in the air before putting it in drive to spin them, right?
this way will help to isolate bearing issues, correct me if I'm wrong please.

during a month of search in this forum I ran into that thread you're talking about for the diff mounting isolators and already checked them on mine, they all sound good.

 

[WildThng]

I had the same problems.
Check your rear wheel bearings.
Raise the rearend and try to wiggle the rear tires.
Nothing should move.

If it wiggles, they are bad.
You will need to remove the whole knuckle and have someone press the bearing. It will take a 15 ton press.

 

[muzzymaniac]

I'd look at the front wheel bearings or the vehicle being out of alignment. Alignment is cheaper.

Alignments don't cause or cure vibrations.
Sounds much like a bad wheel bearing. I've had them go bad and couldn't find any play in the wheels. The hum is the key.
My front one has been driving me nuts - I really need to get on that.

 

[essam]

thanks to all who contributed to this thread. finally i got rid of the vibration and here's the update:
vibration was composite i.e. resulting from two factors, first was cracked engine mounts causing dash rattle and acc pedal vibration (minor cause) and the second (was getting worse day after day) is the front right wheel hub!
no play whatsoever, no loose ends, nothing except for the hum and floor vibration. recently (how i suspected a bearing) i started to hear louder hum once steering left at rather high speeds.
to my surprise, once we removed the faulty hub it was badly jammed to an extent you can hardly turn it and once you do you can feel the friction.

engine mounts were replaced by OEM parts, hub was some brand i never heard of, but it looked good.

at last, my ex runs smoothly purring like a kitten

thanks all, appreciate your advise