Hydro Assist Steering - Legal?

[ARB87U]

It would seem that a brief look at the ADR shows that it would be legal, as a failure of the hydro ram would not prevent the steering system from being used. The only trick might be how to make the driver aware that the ram has failed, perhaps based on pressure in the ram or something.

Bad time of year to be ringing around engineers, as the eventual goal will be a full engineers certification does anyone know if this kind of modification is permitted?

EXTRACT FROM ADR

7.1. Steering System

7.1.1. The centreline of the steering control must not be located to the left of the centreline of the vehicle.

7.1.2. Failure of any non-mechanical component of the steering system must not prevent effective steering of the vehicle.

7.1.3. Vehicles with 'full power steering equipment' shall be capable of providing steering failure and defect visual warning signals to the driver.

7.1.4. Vehicles complying with the technical requirements of UNECE R 79 shall be deemed to comply with Clauses 7.1.2 and 7.1.3.

[AJ]

I'm pretty sure Geoff (Miraz / Wayfarer) from the SJC is doing this on his JK so could be worth asking him, if he doesn't chime in soon.

Oh yeah and WELCOME BACK mofo !!!!

[ARB87U]

Originally Posted by AJ

Oh yeah and WELCOME BACK mofo !!!!

Aint back until the heap is on the road. Got a long list of crap to get done

[ARB87U]

I cannot have been the first to entertain this, the steering box and pitman arm are under massive strain, even on 33's. Is it the word 'Legal' that is preventing responses?

[SeaComms]

Under the letter of the law, if the assistance system fails then the underlying manual system must be capable of still steering the vehicle for it to be road legal. Read that as no drive by wire steering systems are allowed. Basically all you are talking about is a variation of a power assisted steering system. I would imagine though that fail safes would need to be in there, ie, if the assistance to one side fails it should stop working completely, not push it hard across to the other side.

I would find an engineer you can talk to to, as it will have to be engineer approved anyway, so you may as well find one now.

[Jimmyb]

Pretty sure I remember a Hilux in Qld that had hydro assist, and has the ability to turn it off when road going. But dont quote me.

[rainman]

one of the SJC black jk's has it, & its enginered and on the road. cause what is ok in one state may be different in another......hang on it could be Geoff from the above post. I do remember He is an aircraft engineer.