Chassis Drilling

kingfisher21, Jan 11, 10:23pm
Vehicle in question has a seperate chassis, 2001 Grand Vitara, are you allowed to drill through the chassis? Purpose is to mount a A-Frame towing mount at the front.
msigg, Jan 11, 10:29pm
Well you shouldnt really? There are normally a few holes you may be able to use if you change your bracket. Otherwise i would do it myself? Note i said "I not you". Im an engineer and know my work. Each to their own.
muzz67, Jan 11, 11:43pm
Will it need cert? Used to be over 1000kg needed it.
Check with certifier wether holes are ok.
kazbanz, Jan 12, 1:06am
I DON'T know the answer but aren't they illegal now? --front a frames
martin11, Jan 12, 1:07am
Also what are you towing it with ? It may need Brakes to be activated from the Tow vehicle . Its a heavy vehicle .
kingfisher21, Jan 12, 4:43am
OK, yea towing a 1500kg Vitara, will have a brake device fitted eventually, and no, a-frames aren't illegal or in fact even have to be certified as far as I can tell, only real requirement is they have to be 20mm at least behind the very forward most part of the vehicle. Actually just spoke to a guy that re-vins and certifies written off vehicles and he said pre around 2005 you can drill the chassis as long as its not done in a way that strucally really weakens it, ie no real big dirty holes going through near welds etc, after 2005 it get a bit trickier as most manufacturers went to hardened stell and spring type steel with chassis and they are a bit of a no no to drill or even touch what so ever, so looks like I should be good to go, only have to drill one hole per side as the a-frame mount lines up with one existing hole already.
lookoutas, Jan 12, 9:15am
There is no way in hell that I would ever do that! And tell someone.
On the other hand - Is there any way something can be added (properly) to the existing bracket to pick up another hole, preferably further back?
Or ultimately use the existing bracket and the added template to make a whole new bracket with no joins to be picked on. That's my 55 years of practical advise.
mechnificent, Jan 12, 9:26am
Yeah chassis are meant to buckle in a controlled way in a crash. They have holes in them to cause that controlled collapse. Drilling new unplanned holes is going to completely change how it performs in a crash, and I can't see that being acceptable.
kingfisher21, Jan 12, 9:27am
The mount in question is made my a professional and certified company in Hamilton and they have been fitting them the same way I will be doing it for years.
franc123, Jan 12, 9:44am
Given that vehicle pre dates the legal frontal impact standard threshold being a pre Oct 2003 MC class vehicle there are no specific rules surrounding A frame attachment as long as its:

is attached to the chassis by means other than welding,
the components are fit for purpose,
the brackets remaining on the vehicle when the A-frame is removed are recessed behind the forward surface of the bumper by no less than 20mm.
the brackets are fitted so that they do not bridge the vehicle’s crumple zones.
the brackets are fitted so that they do not significantly stiffen the front of the vehicle.

If none of that is an issue it won't be a problem.
kingfisher21, Jan 12, 9:45am
The mount came off a vehicle identical to mine and was originally fitted by the above company. So I'll be fitting it the same way as it was designed to do, all I was querying was the drilling of the chassis and after talking to the certifier on this particular vehicle it is totally acceptable to do so.
lookoutas, Sep 29, 8:19am
Well there ya go.
Does it have to be certified?!