What's causing my knocking?

[muckyman]

Guys, my 182 is knocking at the rear when I lift off the gas / engine braking.
It sounds like the rear exhaust is knocking on the floor, but having poked around this morning I can't see anything loose.
The dogbone and driver side engine mount were replaced this morning and no change (although the gearbox feels nice and tight now).
The rear exhaust mounts are yellow aftermarket inserts, held in with cable ties, and they are not loose - but could these be the cause of the knocking? Maybe switch them out for OEM?
What else at the rear of the car could be causing knocking under engine braking?

 

[con1981]

My 172 is doing the same it is the exhaust clamp bouncing off the rear axle

 

[muckyman]

My 172 is doing the same it is the exhaust clamp bouncing off the rear axle

Solution?

 

[Addicted]

Buy new exhaust mounts, they sound fucked if they are banging that badly.

 

[con1981]

Buy new exhaust mounts, they sound fucked if they are banging that badly.

Or short term become a cable tie mechanic!

 

[muckyman]

The exhaust mount are new (a few months ago they were replaced with aftermarket 'poly' mounts).
Could it be that these are simply too 'hard' and causing the knocking?
I'll have another look underneath next weekend to see if anything is obvious.
Where should there be mounts? Just asking in case I'm missing one that I haven't spotted yet.
The two aftermarket ones are at the back boxes, but what locations should have others (pics would be good)
ta.

 

[bampot]

Maybe exhaust is sitting too high and knocking the boot floor? How much gap between that and the back boxes?

 

[muckyman]

Maybe exhaust is sitting too high and knocking the boot floor? How much gap between that and the back boxes?

It seemed fine when I looked a few days ago and the exhaust tips are perfectly aligned to the bumper cut outs but I'll check that again next weekend when I can get access to a ramp.
Any other suggestions from anyone?