Hey folks,

I replaced my rear diff mount a few months ago and the main knocking has gone. However, I'm still getting a faint knocking from rear, specifically when doing maneuvers like reversing slowing in to space... slow clutch work basically, where I'm coming off/on the clutch frequently. It doesn't really occur when accelerating harshly/changing gear.

My rear subframe bushes have a bit of play in them. I'm not hugely familiar with a 4 wheel drive set up as this is my first 4wd car. I know there will be a lot of torque being shoved to the rear of the car, but would the rear subframe bushes being tired causes a knocking?

Any help would be awesome, thanks dudes !

Matt.

Does the knocking happen when applying brakes or when letting clutch in/out ? Quite common for brake pads to clunk in reverse.

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It happens when letting the clutch in/out... it feels like there is a thudd towards the rear also, like the power is being shoved back but something is worn out and not supporting the power properly.

I've not had a 4WD car before and I'm not sure if this is standard for 4WD vehicles, whether this is a characteristic of them?

Thanks dude!

Centre propshaft mount is another thing to look at. These can go soggy with age.

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Rear subprime bushes have play
Can you explain that a bit. Do you mean the subframe is able to move about?
If so I would say this requires immediate attention as something is potentially wrong. Check all the subframe mounting bolts as a matter of urgency. I suspect if the subframe moves some of the bolts have failed. This is not unheard of

Ah okay, so the subframe bushes are meant to have a small amount of play?

I don't know if the subframe itself is moving about to be honest. I will give the mounting bolts a good check over this weekend though! I'm just thinking of a few ideas at the moment really as I don't know what is causing this knocking.

I'm relatively new 4WD cars, so I don't know how much movement there should be in the drivetrain etc. Should you noticed any movement when coming off gas or on/off clutch driving (traffic jams etc)?

I've had the car at TGT and they couldn't find anything obviously wrong, but I can feel movement when reversing with on/off clutch work or traffic jam driving. There is a definite knock towards the rear when reverse parking for example.

I might get the car on ramps at the weekend and have a gander.

Thanks for the help so far Nibbles/two_OH_five! Much appreciated.

No the rear subframe should not have any play that is detectable!

A clunk that mostlyhappens in reverse could be the exhaust on the rear floor if it has an aftermarket system but you say that it feels like there is movement of the rear frame.
Does the car feel difficult to reverse in a straight line?

What about brake clunk when reversing? Could that be a possibility?

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I had a rear subframe bolt break on my ST205. Symptoms were a knocking noise like the exhaust was loose.

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Thanks for the help guys! Much appreciated.

That doesn't sound too good then! It doesn't feel difficult to reverse in a straight line.

I will get the car on the ramp, at the weekend to check for the exhaust knocking and broken subframe bolts. I will double check for bush play too.

With regards to brake clunk, is this the pads not leaving the disks properly? What would cause that?

Thanks again dudes.

Brake clunk is caused by caliper design. The pads can move fore and aft a smidge.
Normally they are held forwards by a spring clip so when you hit the brakes the pad is already hard against the caliper and makes no noise.
When you brake in reverse the pad grabs the disk then moves backwards in the caliper until it actually hits the caliper - with a small clonk

Before you make any rash decisions, I had knocking like that and was just arb droplinks. Very cheap and easy fix, so worth looking at or even just replacing as could feel NO movement in mine, but once replaced, knocking went.

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Ah okay. I never thought of that. I replaced them a few months back with some ones off eBay that were recommended. They were cheap enough, so if I can't find anything wrong, I'll try them! Thanks dude.

Droplinks normally knock on uneven bumps.

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What about rear diff mount? Dorris

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