1998 S40 - New member and... vibrations problem > 70mph

[osakalevin]

Hey everyone,

New member here from Portugal. Hope all are well and healthy during this never-ending pandemic.

First and foremost, I've been reading a lot on this forum but never registered. I'm from Portugal and currently daily-drive a 98' S40 1.9 T4. It's been with me for the last couple of years and I can't seem to have enough from it, let alone think about selling it. Here's a picture of the culprit:



Unfortunately the car has an issue that I can't seem to solve: It starts to vibrate (slightly, nothing major) after reaching 70mph and continues on. Below this speed it doesn't vibrate (or at least I don't feel it). The vibration doesn't get much stronger if driving at 70mph or at 100mph, for instance.

I've searched the forum before opening up this thread and found several threads talking about vibration (specially on the S60 D5), but nothing exactly like mine. Not sure if you have any specific word for it, but I searched for 'vibration, juddering, shaking'. Also, I'm not sure if this was something common on the 1st gen S40's. For now I can tell this much:
- Wheels are balanced (no weight has come off)
- All 4 shocks were replaced last year (uprated), together with new springs (H&R)
- The car did vibrate when braking. The 2 front hub's where replaced as well as the discs and pads - Braking vibration is now gone.
- Tires are not new, and have around 12.000 miles left.
- Most suspension mounts have been replaced (not engine).

Does anyone know if I should look for any specific tell, a specific mount or part?

Thanks in advance for any help.

All the best and stay safe!