Make sure it’s actually the supercharger. Plenty of “SC bearing” noises turn out to be a tensioner, idler, alternator decoupler, or even the crank pulley. Two quick isolation tests:
- In VIDA: ECM → Activations → Supercharger clutch. Toggle it on/off at idle. If the noise appears/disappears with the clutch, that points squarely at the SC.
- Physical isolation: briefly unplug the SC clutch or remove the SC belt (if equipped separately) and start it just to listen. If the noise remains, look hard at the FEAD idler/tensioner and alternator OAD.
A quick price sanity check, new OEM SC assemblies are commonly $1.1–$1.4k online. Add:
- belt + tensioner/idler: $150–$250
- intake/throttle gaskets + misc: $50–$80
- labor: ~4–6 hours
A good Volvo indie usually lands $1.8–$2.6k out-the-door. A dealer at $3–$4k happens, but you’re not crazy to balk, especially if they handed it back noisy after the t-stat job.
If it were me, I wouldn’t keep driving it noisy. If a bearing seizes you can spit a belt and get stranded. Diagnose/decide soon. Given (a) it left with dead batteries after the engine swap and (b) you noticed the noise right after the thermostat housing work, politely escalate to the service manager/GM and ask for parts price-match to online OEM and/or a labor concession. Calm timeline + invoices helps.
These cars have a main AGM and a small support battery and both are wear items, but if they delivered the car with weak cells, that’s on them. After replacement, ask for a BMS reset in VIDA so charging logic is correct. For the fob, start with a CR2032. If you only have one working fob, budget a new one plus programming ($350–$500); used fobs can’t be re-married to your car.
What I’d do in your shoes
- Verify the noise with the VIDA clutch test / belt off.
- If it’s truly the SC, get a written quote from a Volvo-savvy independent using OEM parts.
- Take that back to the dealer and ask them to meet it (or close) given the recent history.
- If you plan to keep the XC60 2–3+ years, fixing it makes financial sense. If you’ve lost confidence, disclose the issue and sell as-is, you’ll usually take less of a hit than raiding a 401(k).
Bottom line: $4k isn’t unheard of at a dealer, but you likely have a solid $2k-ish path at a good indie, after confirming it’s not just a pulley/tensioner. Happy to sanity-check a quote or help you map the VIDA steps if you post codes/noise details.