My 1998 Explorer is making a terrible banging noise when driving. It appears to come from the rear. It only occurs when i step on the gas, gives a bang and the car shudders lightly. The bang can be gone for 10 - 30 seconds, and all of a sudden appear again. If I step hard on the gas, it will make a bang! bang! bang! noise.. If let my foot off the gas, it rolls quitely without any noise.
I have greased the slip yoke, inspected the U-joints, checked the rear calipers, opened the rear axle/differensial plate - no metal parts or eccessive wear were observed..
The transmission runs smoothly, there are no other noises apart from the bang. It is as if someone is hitting the car with a hammer from underneath...

Any suggestions are appreciated!

 

Rear spring shackles?

 

Thank you for the tip.
Have checked the shackles, , but it all seems fine. All nuts were tight and no playing.
Any other ideas?
The play in the differencial and axle seems also fine.
The bang/clunk appears when I step on the gas or just riding normal on the road. It doesnt matter how fast.

I might place a camera under the car and see if it shows anything interesting..

 

sounds simple stupid, but did you look at the anti-roll bar links?

 

Thanks for the tip. I will leave no stone unturned in this matter, so I will check it out. Any other idea are welcome.

The loud bang has nothing to do with how fast I drive. It appears driving slow around the block or on the highway...

 

I helped a friend find a noise in his 1996 Explorer that matched the description you provide very well. We used my ChassisEar to narrow down the source of the noise to be the transfer case. It only made the banging noise under load.

He purchased a used transfer case from a salvage yard, installed it, and the noise was gone.

-Rod

 

Hi Rod.
Thanks for the tip.

Mine makes this noise without load.. I will try to get a hold of a ChassisEar and see if it brings any result.

 

Here is a video I made from under the car while driving in 20/30 km/h around the block.
To me it sounds like the transfer case sensor is turning itself on and off, causing a banging sound from the drive train. Could it be a poor speed sensor from the wheel hub?
https://www.youtube.com/watch?v=_2eF...ature=youtu.be

 

Check your front drive shaft for excessive play. I chased a sound around and wound up being the drive shaft. The big knuckle near the transfer case went bad. I took it apart but couldn't see how to rebuild it. Got a rebuilt one from DTS and the sound went away. My '98 was 5.0 with AWD.

 

The noise itself sounds consistent with what my friend's was doing, but yours does it a lot more often.

-Rod

 

I think might have found the source.
Took off the drive shaft and noticed some play in the rear axle.
I guess this might be a bit more than normal play?
https://www.youtube.com/watch?v=sARc...ature=youtu.be

Roger

 

I wouldn't say that's an abnormal amount of play. Did you have both wheels off the ground and make a complete revolution to make sure there's no binding or signs of a broken tooth on either the pinion or ring gear? You mentioned in your original post that no metal or signs of abnormal wear were noted when the diff cover was off, so I doubt there's a missing tooth, but still worth a few turns to confirm it doesn't bind up.

-Rod

 

I have just checked the diff good, and there are no chipped teeth or metal in the oil whatsoever., Found this play, but this is normal considering the age..?

Will check the transfer case today

 

Hi guys!
Thanks for all suggestions in this matter.
It turned out to be the transfer case after all.

https://www.youtube.com/watch?v=4GDO...ature=youtu.be

 

I'm glad to hear you found the issue and (presumably) got it fixed. Thank you for following up on the thread with what you found.

-Rod