Underfloor storage: 13 litres. 60/40 split-folding rear seats. The official boot capacity of the Mitsubishi ASX is about 442 litres of space. However, when you fold the split-folding seats the space increases to 1 193litres. An additional feature that increases the boot space of the SUV is the 13 litres underfloor storage. Mitsubishi Outlander (2012 - 2021) 2.2 DI-D GX4 5d Specs & Dimensions. Mitsubishi Outlander Estate Exceed CVT 4WD 2.0 auto 5d only £19,850 33,870 miles. pfjo2.