The red prototype features a rear axle that is noticeably further back than the standard XC90, with photographers estimating the wheelbase on this vehicle has been stretched by nearly 250mm – for reference, the XC90 has a 2984mm wheelbase.
Also featuring on this test vehicle is a very solid steel platform that has been built over the rear of the car, which is believed to provide extra stability.
Initially it was thought this mule is an early prototype for a larger SUV model or a long-wheelbase version of the XC90, though there has been no word of such a project so far.
It's unknown what exactly this Volvo prototype is, so we'll have to wait and see if it starts to drop the XC90 disguise as it progresses through its development.
What do you think is under the skin of this Volvo XC90? Let us know in the comments below