LR2 3.2 Owners,

I just watched a video of a XC90 3.2 with a failed Thermostat.

The surprising thing is that the failure mode appears to be non standard.

Common failure mode for 3.2 Thermostat

1. Cracked plastic due to return spring shear force and thermal cycles (Fatigue or Creep rupture is the likely phenomenon)

2. Plastic failure of the O-ring groove at its thinnest section


Mode #1






Failure mode #2

Arrow point at location of the failure, I'll search the internet for the picture of the failed part






New Failure mode




Conclusion

I would need to get a closer look at the actual part to confirm but it appears that the plastic housing has deformed due to heat. Two possible reasons.

1. the coolant leaked out and engine got very hot and this warped the plastic

2. an aftermarket Thermostat was used and it was built with an inferior plastic

Beware of aftermarket parts for components like this.

Here is the video

Thanks

Paul



Recommendation

Get the Thermostat in a Volvo box or Land Rover box.
Don't buy aftermarket.
And change it every 10 years