Knocking sound at the differential and gear housing that intensifies with increasing speed

If this is knocking and increases in speed as you speed up then this is something related to a rotating object and more than likely the gears in the differential.

Can you get a recording of this noise? That will help with making sure we are giving good advice.

However, based on this info I would suggest putting the vehicle on jack stands and driving it with the wheels in the air to try and zero in on the area that this is coming from. Here is a guide that will help with this:

https://www.2carpros.com/articles/jack-up-and-lift-your-car-safely

If I am correct and this noise is coming out of the differential then you are going to have to disassemble and look for metal or broken components

Unfortunately we don't have a manual on this vehicle so we don't have any specific info but here is a guide that will help with grinding noises:

https://www.2carpros.com/articles/vehicle-grinding-noise

Please run through this material and let us know what you find when you put it on jack stands. That would also be a great time to get the video if you can. Thanks

Thank you for replying to my car question.

I did stand the vehicle on jack-stand and had it run on fifth gear over the week-end and the following are the latest findings
1. The knocking from the differential vanishes - it only appears when the wheels are on the ground (bearing the weight of the vehicle) and driving above 20km/h
2. Left wheel spins slow as I mentioned in my initial question but something else surfaced - the left axle bearing must have been damaged. It sounded similar to a damaged wheel bear and I could feel the vibrations.

I am going to check on that axle and its bearing and replace the bearings (LHS and RHS.) Do a test drive to see if the knocking sound still exist before I will proceed to attempt on the differential work.

I will see if I can record a video of the knocking sound and post later.

I did had a look at the links after posting my initial question but thanks all the same for your help. Will keep you updated as I continue on this diagnosis and repair so others facing similar issues can use the information.

Willie Mondo

Okay. The wheels are not going spin at the same rate when on jack stands as this system is not meant to run with no load so don't let that influence your direction.

As for the noise if it only does it when there is a load on the vehicle then it is most likely at bearing noise. It could be a wheel bearing or differential bearing.

https://www.2carpros.com/articles/how-to-replace-front-wheel-bearings-and-seals

A recording of it will really help narrow that down because bearings make pretty common noises.

Let us know what you find with this and we can go from there. Thanks

Okay, I realize my mistake in my reply to the first answer.

I did a manual check on both wheels by hand (engine off and gears in neutral) and found the left wheel was sort of stuck and produced noticeable play. Clear grinding sound coming from the wheel side and tiny but audible clanking sound from the differential housing. I am pretty sure the axle bearing is damaged.

The wheels are supposed to be spinning smoothly and without much play or grinding noise if spun by hand. Therefore I will check on the axle bearing first this weekend, then proceed to the differential. I have done wheel bearing before so I will be okay with that.

Okay. That is great info and you are correct. I am attaching a process from the manual on a similar vehicle just in case you or someone else needs it.

Please let us know if you have other questions and how you make out once you get it repaired. Thanks again for the clarification.

Thank you.
Just a clarification - this is a rear drive axle issue so information from this link (https://www.2carpros.com/articles/rear-axle-seal-replacement) would be handy in my case.

Sorry. You said that earlier. Thanks for clarifying that for us and attaching that article.

Please let us know how this turns out. Thanks