Slight shudder from rear above 65mph

[Pappa583]

What could cause this? Feels like the rear wheel is ever so slightly out of balance, but ive just had all 4 wheels balanced, front was off by 35 which explained the slight wheel shake at 70mph but although this has now disappeared it feels like there is a slight shudder/bounce through the car from what feels like the rear?

Hard to explain but I can feel it through the car above 60-65 mph, although doesn't seem to be there all the time?

I've checked tyre pressures and was talking to the guy when he balanced the wheels so know he done all 4 and was only slightly out on rears, originally anyway. 

Just wondering if anyone has experienced similar before I head back and maybe get the rears rebalanced again.... just thinking of the obvious things first. Couldn't feel the slight shudder before as the front wheel was out of balance anyway so prob masked this?

Car has only done 38k miles and sounds silent so doubting a wheel bearing or gear train issue? Well more hopeing its not 🤞

[Magnet]

Hello Paul,

Tyre brands and tread wear compatible across each axle ( and ideally all matching on AWD-? 
Logic points to rear balancing if felt through the car, and your seat. If the rear imbalance wasn’t there before, then I would be getting the rear balance rechecked. 
You say you’ve checked the tyre pressures - before or after balancing? Were the tyre pressures checked when cold and set to Audi’s figures? I ask since my experience leads me to believe that most tyre retailers never ask what pressures you use, and it’s not uncommon for them to fit tyres and not even have matching pressures. 
If the vehicle has been driven for an hour, you will find that the pressures will have increased by 3 to 4 psi, so well worth setting pressures after being parked up overnight. 
Kind regards,

Gareth. 

[Pappa583]

Ah well, its not the wheel balancing..... and not the tyre pressures.... not sure what to get checked next to be honest, hopefully something simple but I doubt it......

Ever so slight a bounce/shudder, maybe nothing and I'm just being over sensitive 😳.....

Just have to put up with it till it gets bad enough that it's obvious I think

[Magnet]

Thanks Paul,

You don’t tell us whether you have the rear wheels rebalanced (once tyre pressures were correctly set).

You don’t tell us anything about tyre brands/patterns across the axle, or any indication of whether tread depths are even. 
Kind regards,

Gareth.

[Autobarn]

Not sure what make the tyre are of if you have found one of our nations many pot holes recently but I had a Q7 in recently with almost exact same issue, the rear tyres were mid range economy brand and one had broken wires in the rubber compound leaving it slightly oval as a result, this is not picked up or effected by balancing but can be found by your tyre guy by fitting on machine and holding a tool like tyre bar or big screwdriver next to tread whilst spinning, if you want to find which one it is yourself, swap one side from front to back, if vibration moves to front from back its the one you changed, if it does not it is the other rear, it is very unlikely to be anything mechanical because the diffs on these are proper not haldex diffs which vibrate for fun 

[Pappa583]

Passing a local tyre place yesterday on way home in decided to call in and get these balanced again as it has been bugging me.... alot... and one of the rears was out!  Can't understand it as I watched the last place do them and the weights were fitted where the machine told him. 

Drives so much better now so happy days..... 😊 

Know where to go in future, and where not..... 🤣