Grinding Noise with caravan

[DazzlerB1]

Hello all. I’m looking for as much help and information possibly of where I begin to identify the Grinding noise we’ve experienced. So we have a 2007 KJ 2.8 car drives lovely. But…… (there’s always a But) this is the third time in towing and this is the first time it has happened. After a good 10 minutes possibly less we get this constant metal on metal sounding grinding noise, it’s never happened before. The issue we have is it stops as soon as the caravan is in hitched. It seems that once the KJ is under load/weight there’s something that starts to rub or grind together, or possibly carrying the excess weight makes it grind. It sounds central but with listening out of the window it’s very hard to tell. The brakes have recently been changed, but I need as much help before I take it to the garage.

Thank you all for you help.

 

[LibertyTC]

Sounds like a drive-line issue, U-joints, prop shaft, have you changed the rear diff fluid lately?
It may be best to get it on the lift for a full inspection.
While on lift in drive, the grinding may present itself quickly.

 

[KJowner]

Old springs sagging with the extra weight? Have a look at the plastic arch liners and see if it's rubbing.

 

[DazzlerB1]

Sounds like a drive-line issue, U-joints, prop shaft, have you changed the rear diff fluid lately?
It may be best to get it on the lift for a full inspection.
While on lift in drive, the grinding may present itself quickly.

Thank you. Something will get the garage to check.

 

[DazzlerB1]

Old springs sagging with the extra weight? Have a look at the plastic arch liners and see if it's rubbing.

Possibly as the car was full as well as the weight of the caravan, would this make a grinding noise that sounds like metal on metal but also sounding like a rotation motion? Something I’ll check tomorrow? Anywhere in particular?

 

[DazzlerB1]

Could it also be coming from the transfer case? Although driven in 2wd could this possibly be grinding?

 

[KJowner]

I doubt it, the transfer case is working whenever you are moving, I'd be looking for something that's rubbing when the suspension is compressed, the other suspect is the LSD if you have one, that can make some nasty noises when turning, mine did until I changed the oil and LSD fluid.

 

[duderz7]

I vote u joints. With age they will sometimes wear in at the normal ride height angle. When extra weight is on board it changes drive line angle and is no longer riding in the worn in section.

 

[DazzlerB1]

I doubt it, the transfer case is working whenever you are moving, I'd be looking for something that's rubbing when the suspension is compressed, the other suspect is the LSD if you have one, that can make some nasty noises when turning, mine did until I changed the oil and LSD fluid.

But with extra torque would this maybe contribute to it? I saw another online video of someone with the same noise as ours that was the transfer case. This isn’t a rubbing, it’s a definite grinding metal noise and sounds like a rotation noise.

 

[DazzlerB1]

I vote u joints. With age they will sometimes wear in at the normal ride height angle. When extra weight is on board it changes drive line angle and is no longer riding in the worn in section.

Is there a way of knowing or checking before sending to the garage?

 

[DazzlerB1]

I doubt it, the transfer case is working whenever you are moving, I'd be looking for something that's rubbing when the suspension is compressed, the other suspect is the LSD if you have one, that can make some nasty noises when turning, mine did until I changed the oil and LSD fluid.

Also LSD? Sorry I’m not sure what that is yet

 

[sleazy rider]

Also LSD? Sorry I’m not sure what that is yet

Limited Slip Differential - the rear axle pumpkin.

 

[DazzlerB1]

Limited Slip Differential - the rear axle pumpkin.

Thank you

 

[DazzlerB1]

One other thing to add once we went through a large puddle/flood it stopped for about 5/10 minutes. Almost like it cooled down and then heated up again. Just want to know what to suggest to the local garage

 

[sleazy rider]

One other thing to add once we went through a large puddle/flood it stopped for about 5/10 minutes. Almost like it cooled down and then heated up again. Just want to know what to suggest to the local garage

Honestly? As a retired techie, just give the service manager a list of the symptoms and I’ll divide/conquer on potential issues and figure it out stat. Not much to a drive system.

 

[duderz7]

Pull up.some videos on checking u joints and for lsd.

 

[DazzlerB1]

Honestly? As a retired techie, just give the service manager a list of the symptoms and I’ll divide/conquer on potential issues and figure it out stat. Not much to a drive system.

Thank you, will do. I just wanted to eliminate as much as I could but that’s proving hard to do

 

[DazzlerB1]

Pull up.some videos on checking u joints and for lsd.

Thank you, will do

 

[KJowner]

One other thing to add once we went through a large puddle/flood it stopped for about 5/10 minutes. Almost like it cooled down and then heated up again. Just want to know what to suggest to the local garage

That would suggest brakes to me, time to pop the wheels off and have a look.

 

[DazzlerB1]

That would suggest brakes to me, time to pop the wheels off and have a look.

These have been recently replaced, you cannot hear the noise after the caravan is unhitched, also it still happens when the brakes are applied.