Hennessey Mammoth It’s huge… but the really huge thing is its horsepower

Performance tuner Hennessey turns the Ram TRX into a six-wheeled leviathan with 37” tyres, two rear lockers – and a supercharged V8 engine developing 1012bhp

Words: Olly Sack Pictures: Hennessey Performance

If you read last month’s issue of 4x4, you’ll 4x4, you’ll have spotted the story of how a meek 88” Series II Land Rover became a hefty great 6x6. With a dropside pick-up bed made of hardwood planks, the vehicle has all the charm of a classic work truck – though with its twicereconditioned 2.25 petrol engine putting out 74bhp, it’s unlikely to be seen as a street sleeper.

In this way, it’s similar to the Hennessey

Mammoth. Both have six wheels, all of them driven. And neither is a sleeper. In the case of the

Mammoth, though, this is not because it has a

Performance tuner Hennessey turns the Ram TRX into a six-wheeled leviathan with 37” tyres, two rear lockers – and a supercharged V8 engine developing 1012bhp

comedy horsepower output: it’s because it looks like a surface-to-surface missile.

If you were to take the wings off a Lockheed Blackbird and put it on wheels instead, the image you’d get is not unlike the one the Mammoth creates. There’s something slightly freakish about it – but in a splendidly breathtaking, menacing way.

That’s why it’s not a street sleeper: nothing this evil could ever claim to be such a thing. Which takes a bit of getting your head around, because when could a 1012bhp pick-up truck ever be anything else?

Yes, you read that right: 1012bhp. And there’s 969lbf.ft behind it, too. Hennessey already does a 4x4 version of the same vehicle, for which it claims a 0-60 time of 3.2 seconds; the 6x6 can’t help but be heavier (it’s four feet longer than standard and, in case we hadn’t mentioned it, has an extra axle), but we’d still expect it to monster anything short of a fully fl edged supercar.

Talking of the vehicle’s length, this comes out at a total of 283”. That’s not quite two Land Rover 90s, but only by about a foot and a half. So, yes, it’s big.

But it’s all in proportion. A set of 37” tyres on 20” hard alloys sees to that. The vehicle is held up by Bilstein suspension and is fi tted with not one but two rear diff locks – and of course it has a monumental load bed. So, they’ve taken an offroad utility vehicle and made it into even more of an off-road utility vehicle, right?

The vehicle in question started life as a Ram TRX. Not exactly slow from the outset, then – this already comes out of the factory packing a 702bhp V8 lump capable of squirting it beyond 60mph in 3.7 seconds.

Above: The Mammoth 6x6 is one of the very few vehicles in the world that are able to boast of having rear diff-locks (plural). Like the Ram TRX on which it’s based, it’s held up on remote-reservoir Bilstein suspension; Hennessey has added a levelling kit at the front Below right: There’s not a great deal to see under the Mammoth’s bonnet. But there’s defi nitely a whole lot to hear when the supercharged 6.2-litree Hellcat V8 cuts loose – not to mention even more to feel. A monstrous output of 1012bhp and 969lbf.ft sees to that – it’s as fast as a modern supercar, despite weighing about as much as the factories that make them

All good, but Hennessey has built its reputation on taking incredible cars and making them still more incredible. The company’s engineers rebuild Chrysler’s 6.2-litre Hellcat V8 using a high-fl ow 2.65-litre supercharger and upgrades to the fuel injectors and induction system, fi nishing the job by recalibrating it to make the most of all this extra hardware.

There’s more to it than just that, of course. The spark plugs, thermostat, crank damper pin and supercharger drive belt and pulleys are all upgraded, and the fi ltration and ventilation systems are amended to suit.

Then comes all the off-road kit, including Hennessey’s own heavy-duty front and rear bumpers – the former with its own integrated light bar fl anked by a quartet of LED cubes. Inside, the headrests gain Hennessey logos and there’s a numbered build plaque on the cubby lid – mirroring another on the engine cover, should you feel inclined to double-check.

‘Everything we do at Hennessey Performance is turned up to 11,’ comments company boss John Hennessey, ‘but the Mammoth 1000 6x6 is defi nitely turned up to 12! Everything on the Mammoth 6x6 is bigger, badder and more imposing – plus, it’s still super-fast, while being a total powerhouse off-road.’

Big numbers all round, then. Warranty-wise, on the other hand, they’re a bit smaller, with 24 months or 24,000 miles of cover on the Mammoth 6x6 – compared to the 36 months or 36,000 miles, with 60 months or 60,000 miles on the power train, which Ram offers on the standard TRX.

Another very small number is 12, at least when it’s the number of vehicles that will be built each year. But it’s good to know that when you park your 1012bhp ultra-truck outside Lidl, the chances of being another one there already are slim enough to cope with.

Back to the big numbers, Hennessey says the Mammoth 6x6 will be priced ‘in excess of $449,950.’ So, about as much as six Ram TRXes, then. Just think of it as one donor truck per wheel.