Auto Gearbox: car recovery from trackside 'off'

[anonymous-user]

This is 'theoretical' and I hope will never happen... I have an M135i with auto gearbox that I occasionally use on Track Days. If [heaven forbid] I should go 'off' and need to be recovered, is it possible to be towed, with the engine running and the GB in 'N'? BMW state quite categorically that the car must NEVER be towed and of course it is impossible with the engine stopped. I have briefly coasted the car downhill in neutral with the engine running; so, is there a technical reason why this would be a bad idea?

[Hugo a Gogo]

lift it by the rear?

[anonymous-user]

Hugo a Gogo said:

lift it by the rear?

Might work, thanks, 'course track day recovery trucks will sling their hook around anything they fancy - but crumpled bodywork may be less expensive then a broken transmission...

[AdiT]

Towing a short distance at low speed shouldn't be a problem. If it was going to instantly destroy the 'box then you couldn't even pull it onto a flatbed or push it around a workshop.

Curious as to why it's "impossible with the engine stopped"? Brakes would be poor (with no servo) and steering heavy without power but not impossible.

[hman]

my bmw auto advise that it could be towed at sub 40 mph for less than 40 miles I think?


anyway I was towed a couple of times - normally 10 miles or so at 30 mph - no (additional) ill effects.

[anonymous-user]

AdiT said:

Towing a short distance at low speed shouldn't be a problem. If it was going to instantly destroy the 'box then you couldn't even pull it onto a flatbed or push it around a workshop.

Curious as to why it's "impossible with the engine stopped"? Brakes would be poor (with no servo) and steering heavy without power but not impossible.

When the engine is switched off, the Steptronic box is automatically software locked in Park and so the rear wheels can't move. The only recommendation in the BMW manual is for the vehicle to be hoisted onto a flatbed truck! It is possible to roll it engine off in Neutral; I asked my local BMW Dealer if it can be towed with the engine running in Neutral - but they wouldn't budge from the Official Line.

[CycleSi]

I've always understood it that it's because of hydraulic pressure build up that automatic cars should be towed for as little as possible.

[bennyboydurham]

My E65 has a manual release for the gearbox so it can be towed, although the manual states not to tow it very far and under 30mph iirc.