Shudder-Speed Related

[the dj]

Hi all

I have a 2003 (53) avensis 2.0 t4 d4d. I am getting a shudder/vibration when driving at 55-65 mph. It only hapens when the car has warmed up. When cold i can feel it a little but when warm it is more apprant. I can drive thru the speed and it stops. Also if i release the gas it also stops. It feels similar to wheel balancing problem although there is no vibration in the steering wheel and seems to be coming from below.

I have read the following post: http://www.toyotaownersclub.com/forums/index.php?showtopic=109410

and it seems there are a number of possibilities. However after a garage inspection even though they cannot see any play, after driving it the mechanic said it is definitely a driveshaft problem as he has felt it so many times before.

Recently the car has had new tyres all round and new discs yet we have been able to rule these out. the only other thing that has occured recently is a cambelt replace and full service. Now if my mind serves correct it may have had a slight judder previous to this and initially after the cambelt change i took it on a long run (90 miles) and it was fine. Only a few days later it started to occur.

Now there was a problem with fuel sensor circuit A going faulty after cambelt change but the garage changed that the other day and that has removed the MIL. Obviously I was hoping that may have been the problem!

So now do I buy the driveshaft(s) and get them fitted in the hope it is that? or do I get more advice as the topic post above seems to suggest other areas such as flywheel??? Also when I colected the fuel senso part from toyota dealer I did ask there and mechanic said oh yes common problem..it's the flywheel!!

Now please remember it is speed related and only when warmed up, plus I dont have any problems with clutch or gears.

Any help would be appreciated.

Oh the only other recent change was a starter motor a few weeks previous but that seems fine.