have you checked the steering rack ends for play any alignment is wasted if you have any play in these .

Hello , thank you everyone we think it is gearbox it is to be confirm I just do not have enough time , if get lucky will try next week and will be updating then.

I have the same problem... wheel alignment was done and wheel balance has been checked twice..

My engine mounts are a bit worn so I'm going to get that done this year, I asked the garage to check towards the end of the last year and they said they couldn't see anything... Any other ideas?

Hello , bearings , rod ends , lower arms ( most common) ? I still not have time to complete my car full check again , but I do notice vibration can change time of time sometime very can fill another time just about I do not remember where I was reading about , but something was also can be flywheel too . I do hope get car check next week . Good luck.

Please let me know what happens when you get it checked. It comes and goes on mine too, just drove back to Glasgow from South East England last night and it's the only thing that lets the car down.

The flywheel is interesting, I got my car on 118k miles and it's now on 160k, never changed the clutch or flywheel in my ownership, it could still be on the original so maybe that's something..

For what it's worth, I had the same issue on a car and it took three different mechanics before the answer was revealed and it was a flat spot on the tyre. Two of them missed it. It was ever so slight but at 70mph really made a difference. As you said it comes and goes, it may be dependent on road surface conditions, just as you can notice a difference in noise of the tyre depending on road surface.

Interesting, although the two tyres I have on the front right now were new last year and I've tried rotating them, marginal improvement but the vibration is still there.

Could be a buckled alloy. Its easy enough to spot on a balancing machine that a tyre shop has. They run the wheels at speed for the machine to get its calculations as to where the weights need to go and type of weight to use. If an alloy is buckled, the tyre won't run "true" on the machine. It will wobble.

A buckled alloy can lead to vibration, which can be felt through the steering if its bad enough.

Wheels have been checked for balancing twice and I had the wheels refurbished last year :/

I might get the engine mounts done because they need doing anyway then take it to the more in depth Volvo specialist in Glasgow to get them to investigate.

Sounds like a plan. Sometimes issues like that are hard to diagnose.