Loud bang when 4x4 is on

[Karpov]

Does matter is it normal 4x4 or low.

It goes at least in reverse, maybe on forward too.


Short, sharp and loud BANG. Not allways but for example i drive 200 meters and about two bangs.


Then another weird thing was, i have 4x4 + low range on, i shut them of and reversed on slippery surface. First rear wheels spin like 2wd should be but then sounds BANG and front rears spins too.


Sound comes o drivers side. Joints are new i think. Automatic hub locks seems to work.

 

[MrShorty]

Any chance you have mismatched tires or one tire flat or something? Are you testing the 4wd on a hard, high traction surface?
What you are describing sounds to me like some kind of wind-up or tension in the 4x4 system that builds up until something slips and releases (hopefully it releases cleanly without breaking). The main occasion I have seen this was when I replaced only two tires, meaning I had GoodYears on the front and BFG on the back, and the differences between the two sets of tires was enough to build up tension in the 4wd system.

 

[RangerX]

To me, it sounds like a bad auto hub. When they go bad, they start to sound just like what you describe.

 

[Karpov]

I was driving mud based surface and wet leafed sand. I have four same tires, kumho road venture 235/75/15 and thy have little bit rough coating so they arent normal road tires but not pro offroad tires.

All were pressured well, no flat ones.



Noise comes just about that you say if i understanded right: tires were taking tracton, then slip and bang and new traction.

Car was stuck too and when tires spinned out off traction, bang was heared too some times.


If they are bad automatic hubs, bang should be heared on only low range position em i right?

 

[RangerX]

That is the scenario that it would happen, yes. Years ago when my hub went bad, I noticed it on a steep sandy hill climb.

No, it's not only in 4lo, it's anytime the front axle is engaged.

Now is the time to move to manual hubs.

 

[Karpov]

What kind of manual hubs i choose? I mean manufacture etc.


Because i live in Finland i have to order them from usa...


What happens if i continue driving 4x4 with bad hub?

 

[RangerX]

Warn is the best. There are 1 or 2 other brands, none are bad.

If you keep driving in 4WD with it, the hub will eventually not grab at all, and that tire will not get powered. I don't believe it will harm any other parts.

 

[Karpov]

Okay thanks!

One thing comes to my mind. Can i just remove hubs and but wheels back and drive so i sure know that hub is worn?

I dont have anything good car lifter etc.

 

[RangerX]

Driving with no hubs may be possible, but you risk dirt getting into your bearings.
In your first post, you say the noise is from the drivers side hub. Why not switch hubs side to side, and see if the noise is then from the passenger side?

 

[Karpov]

Heh. Very good hint!

 

[RangerX]

Please keep us posted, you got me involved!
Also, if and when you get manual hubs, you will also need the conversion kit. It's just different locking washers than the auto hub uses.

 

[Karpov]

I switched hubs right to left.

Then i first try 4x4 and low range on iced grass. Nothing happened.

Then i go rough san road with grass sides. 4x4 on started banging when i accelerated. When speed was about 20-25mph bang sound was changed to smoother and thicker. And when i slowed down thickersound begome thinner and bang bang.


Sound is greater when speed is slow.

It feels almost drivers seat. Feels very mechanic. Not just voice.


Forward/reverse no different.


What now? Something bad....

 

[Karpov]

Nobody? Winter is coming and i need 4x4 to moving on

 

[RangerX]

Hmm, I still lean towards the hubs. Maybe both are bad? They ARE 20 years old, and they are well past their normal lifespan...

Try repeating the test with someone else inside the vehicle, and one or two others outside the vehicle. Other eyes and ears may help pinpoint the sound source.

 

[Karpov]

And if hub is wrong, its only the "cup" part which comes trhu wheel? Or can part which is the axle hub side broke?

Sorry bad termns but i dont have all technic words on my head.

 

[Karpov]

I tested myself only 4x4. First sand road. Bangs again (surpise) but i think not so strong and loud what it bangs when low was on / low was on and then 4x4.

Then i tried on asphalt. In every bang car bounced on drivers side. It was like limping.

I continue research when i get buddy to drive and maybe on dry condition with no hubs at all.

 

[RangerX]

Does the bang happen in a repetitive pattern, in relation to the tire and axleshaft rotation? Or is it more random, and in relation to the surface of the ground and areas of less traction?

 

[RangerX]

Karpov, look at this thread, in case you have not seen it: http://www.explorerforum.com/forums/showthread.php?t=232754&highlight=bad+hub

Also this one, http://www.explorerforum.com/forums/showthread.php?t=206722hich which is linked inside the first thread.

 

[Karpov]

Thanks!

How about, is it possible to assembly hubs wrong when i switched they? Of course i btu them so that they placed against rotor/wheel hub with no problems.


First time after switchin hubs and sand road bangin/bouncing was thick and repetive about axle rotation.

Yesterday in sand road it seems like going with axle rotation but not all the time. About one of three.

In asphalt it was thicker than sand and feels like same rhytm with axle but about two of three, not every spin i think.

I must do research (again )

 

[RangerX]

Did you just buy this Explorer and it came with this problem? Or have you owned this vehicle when the 4x4 was operating well?
I still believe it is a bad hubs problem, and that new manual hubs will solve it.
In doing a search, the only other possibility I saw mentioned was the drivers side u-joint can get "sticky" and bind up, but I think that would bang with every rotation of the axle...