Having apparently considered a number of options Ineos eventually went with BMW as its powertrain partner, the fitment of modern and sophisticated straight-six petrol and diesel engines perhaps the biggest divergence from the brief for field serviceability with spanners rather than diagnostic terminals. It’s likely a pragmatic decision based on the need to have emissions-compliant engines as much as anything, though apparently Ratcliffe wanted a bigger motor and, helpfully, it puts some distance between the Grenadier and the gruff four-cylinder diesels found in most classic Defenders.
Given the 2.7-tonne kerbweight both engines have their work cut out but are smooth and responsive, the petrol edging it on horsepower but the diesel, inevitably, winning on torque. Given there’s not a massive difference in refinement we’d probably go with the latter. Both drive through the familiar and well-proven ZF eight-speed automatic and a transfer case of Ineos’s own design with mechanically selectable low range and a lockable centre diff. From here power goes to hefty live axles front and rear, a suitably over-engineered steering box delivering a very traditional 4x4 feel at the wheel, the characteristic lack of self-centring requiring some getting used for those coming from more car-like SUVs.
While much of the heft stems from determination to over-engineer the structure to near-indestructability a good portion of it also comes from an unexpected focus on NVH, and for a body-on frame vehicle the Grenadier is more G-Class than Jimny. You get the odd shudder now and then but, even with off-road tyres and biscuit-tin aerodynamics, you can hold a conversation at motorway speeds, the work on details like bushings, glass thickness and body mounts paying off.
The slow, low-geared steering tempers your ambitions on the road but once you settle into it the Grenadier has refinement sufficient that you might feel willing to cruise from London to that remote Scottish estate for a straightforward shooting weekend, and enjoy the fact you could then drive onto the moor without having to swap your kit into the gamekeeper’s smelly old Hilux. With the secondary transmission lever shifted into low and centre diff locked the Grenadier romps over pretty much anything, the front and rear diff locks (included with the Rough pack and standard on the Trialmaster trim), dedicated off-road mode and hill descent control available as get out of jail free cards if you need them. Here it genuinely feels in its element, the suspension still plush enough occupants won’t take a beating, the sense of over-engineering sufficient you won’t wince at the occasional thud of chassis on rocks or scraping of branches on the bodywork.
The guiding principle of the Grenadier was that nobody was making a 4x4 of this nature any more and, while you’d have expected it to deliver on that in the rough, the relative civility on the road is in fact the biggest takeaway.