Technical Knocking upon deceleration

[Mike1alike]

Of course, ball joint or tie rod play is for front wheels.
The rear on yours must be bearing, you mentioned you did check the wheel nuts being tight first. Is that just nuts holding actual wheel or axl nut too?

 

[hugh w]

Wheel nuts, what are the axle nuts? Those holding drive shaft to wheel?

 

[Mike1alike]

Yes. If that is loose you have that exact play like you have. So check that first.

 

[barbubro500L]

Yes. If that is loose you have that exact play like you have. So check that first.

No.
The indication is wrong.
If the four axle flange bolts are loose you DO NOT have play in the rear wheel hub bearings.
On the Fiat 500, in the rear wheel hub there are two bearings held in tension by an elastic flange. The rear hub is held tight by a large nut that also tightens the elastic coupling to which the axle flange is attached. If the elastic coupling with rubber inside is damaged it can make noises on deceleration. So the rear wheel hubs on the Fiat 500 have nothing to do with those on an old and sad Fiat Punto.
It is important to know that on the Fiat 500 the brake circuit is only one and if you have play in the rear wheel hub, the large nut can come loose completely, in this situation the wheel spindle comes out of the hub completely along with the wheel and the brake drum,, a situation in which if you step on the brake the brake fluid will come out freely from the brake cylinder where there is no longer a brake drum and the car is instantly left without brakes!! the risk of having an accident being very high! This has happened several times, it is not just a sad story!

This is the reason why it is not recommended that someone who does not know the peculiarities of the Fiat 500 change or adjust the tension between the rear wheel hub bearings.

 

[hugh w]

@barbubro500L Are you saying my wheel is in a dangerous condition? (even though all bolts tight) or are you referring only to loose flange bolts?

 

[barbubro500L]

Possibly yes...
The wheel hub is held tight only by this nut that sits under the flange of the planetary axle.
For the maintenance of the rear wheel bearings I would contact a mechanic who knows about the classic Fiat 500.
If you lose the wheel with everything behind it while driving, you risk your life.