BMW Built the Perfect M5 Touring (E39). Then Locked It in a Garage

BMW built the most beautiful M5 wagon the world never got to buy — and we saw it up close in a secret Munich garage before social media could even document it existed.

Article Summary

• BMW secretly built a one-off E39 M5 Touring prototype packing the sedan's 5.0-liter S62 V8 with 400 horsepower and 500 Nm of torque — but it never made it to production due to rear-axle dynamics compromises and concerns over market size.
• In 2009, during the 25th Anniversary of the BMW M5, a select group of journalists — including our own — were taken to a private Munich garage to see the prototype in person, long before the era of social media and YouTube documentation.
• Given the E39's timeless styling and near-universal acclaim among enthusiasts, an M5 Touring variant would have been one of the most desirable BMWs ever made — a practical estate with supercar-embarrassing performance and looks that still hold up today.

There are cars that never make production for good reason, and then there are cars that haunt you. The E39 BMW M5 Touring is firmly in the second category — a prototype so close to perfect, so achingly close to what BMW enthusiasts had always wanted, that its absence from showrooms still stings more than two decades later.

Back in 2009, as part of the celebrations marking the 25th Anniversary of the BMW M5, we were among a select group of journalists invited to Munich for a very private look at M GmbH’s history. The setting was a secret garage tucked away from the public eye, and inside it sat some of the most extraordinary and rarely-seen BMWs ever created — the kind of room that makes a car person go quiet. Alongside the M5 CSL and the never-produced M5 Convertible sat the E39 M5 Touring, parked there as if it were the most natural thing in the world.

This was 2009 — before Instagram, before YouTube vlogs, before every significant moment got documented, shared, and dissected in real time. There were no live streams, no tweet threads, no viral reels from inside that garage. Just a handful of journalists, a few old school cameras, and a car that BMW had never officially photographed for public release. It felt genuinely secret in a way that’s nearly impossible to replicate today.

One Of The Biggest Secrets In Garching

And what a car to keep secret. Contemporary reports from the event indicated the E39 M5 Touring carried the sedan’s 5.0-liter S62 V8, producing 400 horsepower and 500 Nm (369 lb-ft) of torque. In other words, the full M5 experience — just with room for a set of skis, a dog, a family’s worth of luggage, or all three at once.

To understand why this car is so mythologized, you have to understand what the E39 generation means to BMW enthusiasts. The E39 M5 is widely regarded as one of the greatest performance sedans ever made — not just for its S62 engine, but for the way it looked. Chris Bangle’s divisive flame-surfacing era was still a few years away, and the E39 carried a timeless, understated elegance that BMW has been quietly trying to recapture ever since. Long hood, perfectly proportioned flanks, a greenhouse that sits just right — it ages in a way that almost no modern car does. People don’t just like the E39; they love it with the kind of devotion usually reserved for things that can’t be replaced.

What A Design This Was

Now imagine that body stretched into a Touring. The long roofline flowing back, the estate proportions adding visual drama without sacrificing an ounce of the sedan’s grace. A practical, everyday car that could genuinely embarrass sports cars on a winding road. The M5 Touring would have been the ultimate sleeper — the station wagon that had nothing to prove and everything to offer.

So why didn’t it happen? Reporting at the time suggested BMW M shelved the project due to rear-axle and dynamics-related compromises — the longer Touring body reportedly creating challenges that couldn’t be resolved without affecting the precise handling character M insists upon. Concerns about market size are said to have played a role as well, though neither reason has been formally confirmed by BMW in an official statement.

What is confirmed is the car’s place in history. BMW Group Classic acknowledges the E39 M5 was produced exclusively as a sedan, and that the Touring prototype remained a one of one. BMW M’s own heritage materials note the Touring version was only ever made in prototype form.

One car. One secret garage. And a room full of journalists who got to see, just once, what could have been.