Tips and traps - vehicle modification

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ants_oz

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Thought I would try to help people with info on vehicle modification.

There are plenty of traps out there for the unwary so here goes. I will edit this post as things come to mind over time.


Engineering:
This is a BIG topic and I hardly know where to start. Probably the basic rule to remember is that you can't get an engineer to approve something that is otherwise banned. For example, under ADR's there are maximum distances between wheel and guard (clearance) - an engineer cannot approve something outside those limits.

An interesting one is extended or flexible shackles. VSB14 (national guideline for light vehicle modifications) says they shall not be used. I haven't delved into the details for each State and Territory, but I know that in the ACT, that means without doubt, extended or flexible shackles are therefore illegal due to the way the ACT has implemented rules surrounding light vehicle modification.


Complexities between jurisdictions
A lot of people talk about how complex the rules are - I agree, they are. A lot of people say that they can't justify following the rules because they are different between different states and territories. I disagree. You only have a responsibility to ensure that your vehicle is roadworthy in the state or territory in which it is registered.

An example is my wheel and tyre combination. My standard tyres were 255/70R16. My current tyres are 265/75R16. In most states and territories that would make the vehicle unroadworthy (>15mm increase in diameter). But in the ACT, we have adopted VSB14 - which for offroad and commercial vehicles allowed up to 50mm increase in diameter. As long as I'm legal in the jurisdiction I'm registered, I'm legal everywhere.


Insurance - Damages (third party property, fire and theft, comprehensive):
This is a civil contract between you and your insurer to provide cover to some greater or lesser degree, for non0human damages in the event of an incident. There is no legal requirement for you to have this kind of insurance. If your vehicle is modified and you don't tell your insurer, in the event of a claim they may refuse to pay.


Insurance - Third Party (injury - along with your rego:
This one covers people - things that matter. There is a legal requirement for you to have this type of insurance along with registration.

If for example, you have a collision and someone is injured, their injuries and any follow on loss of income etc are covered by this insurance. But if your vehicle is modified to a degree which requires engineering approval and you haven't sought it, then in the event of an accident this insurance may be voided. The scary part is not that you may suffer, but that the other person who has been injured will suffer - their medical costs will not be covered, their loss of future income (which can easily amount to hundreds of thousands of dollars) will not be covered.




If I can, I would like to keep this thread running as a service to you all. If there is something I can cover in broad terms, please let me know and I will do my best. Bear in mind though, I am not an engineer, and I am not a lawyer. But I will do my best to try and help you see through the mess of rules if I can.
 
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Thanks for posting this!

In an environment like ours where we have drivers who have above-average skills and decent vehicle knowledge, it's valuable to remain aware that even if we change our vehicle so that it is better, safer and more robust, if it falls outside the limits specified by law, then we need to make sure that we're covered. In all areas.

I'd point out that the other party's losses (medical, income, repairs) that are normally covered by your insurance will, if your insurance company declines, be payable directly by you.

In NSW, the Motor Accidents Compensation Act defines very low limits for paying compensation due to a motor vehicle accident and I'm going to guess that's similar in other states as well. However, medical bills are astonishing. Loss of income could be staggering, although the Courts will be fairly reasonable. I'm being a realist here, and tempering the warning, but don't assume that "reasonable" is small enough to get a personal loan or extend the Visa card to cover it. The legal costs alone would wipe the average credit card out - I'll have a talk to some friends (they are compensation lawyers and deal with motor accidents, where do you think I get my info from?) and see what the range of legal costs is, typically.

The total cost of a traffic incident can reach several hundred thousand dollars and personally I'd rather buy another house and make some poor sap pay me $500 a week in rent to stay in it, than to fork it over because I neglected to cough $800 so I had a piece of paper saying my vehicle was still legal despite having tyres that were 1.25mm over size.

A good lawyer - the one you'd rather have batting on your side in a courtroom - could easily be on the other side, and if they see a modified vehicle, they are going to hire an engineer to go over that vehicle with a microscope. By the way, that engineer's costs are payable by the loser in the courtroom too. As are that good lawyer's costs. Plus disbursements. Having a decent lawyer look at an incident and provide advice could easily cost over $1,000 - so that $800 certificate starts to look cheap.

I don't believe the point of this thread - or my post - is to rag on at people about making sure that the law is followed because we're do-gooders. The point is to protect your own financial well-being, by paying the smaller amount up-front to ensure that the larger amounts (the costs referred to above) are covered by your insurance, or their insurance, and never your own pocket.

Because a $700,000 damages+medical+legal bill landing in your letterbox is a life-changer that you don't need.
 
Spot on Tony.

And if you, or anyone else has any issues which they would like to see covered in this thread - I'm sure that it can be managed.

What my vision for this thread is, is that for example, someone might ask about the requirements surrounding bodylifts. Or how about side airbags and brush rails. Or rear wheel carriers and supplementary lighting (ever wondered why companies like Kaymar don't rely on the factory lights? There is an ADR which states that vehicle rear lights must be visible from something like 30 degrees off-centre).
 
an example is my wheel and tyre combination. My standard tyres were 255/70R16. My current tyres are 265/75R16. In most states and territories that would make the vehicle unroadworthy (>15mm increase in diameter). But in the ACT, we have adopted VSB14 - which for offroad and commercial vehicles allowed up to 50mm increase in diameter. As long as I'm legal in the jurisdiction I'm registered, I'm legal everywhere.
QUOTE]

Ants having read the document you refer to I am (and I can't believe I am typing this) moving to the ACT! This is another good example of a Code of Practice being ineffectual because it is not law just a code of practice and clearly has not been accepted by all states.

I might have to lobby my local MP to adopt the NCOP for LV as his election platform on 20 March this year!! Wish me luck. :big_smile:
 
:) yes, Canberra has some strange rules Bosshog. At least however, the local gov't here seems (at face value) to be happy to adopt national standards for a lot of things (where a national standard exists).

Conversely, I looked into the situation in Victoria for example - if I recall correctly, their public document was released in something like 2002? Or was it the late 90's? I can't recall exactly. But regardless, it was some years ago. When there has been an NCOP published for several years I see absolutely no reason for relevant state jurisdictions NOT to adopt it. At the very least, I can see no reason why (in the Vic example) why an old local document should still be hanging around with old rules, when the new national document (with patently better, more consistent rules) has been published. I am making a big assumption here, but probably all because some committee in Vic hasn't gotten around to endorsing the NCOP for implementation in Vic yet! For goodness sake - we are paying the public servant's wages!

Example - towing laws. State and territory laws are all aligned when it comes to towing trailers (under 750kg no brakes, over 750kg must have brakes etc)... Several years ago that was far from the case, and caused a lot of people a LOT of problems over the years. All started to come to the fore when grey nomads (mainly from WA where they could tow much higher weights than in NSW) came over east, and got pinged at roadside checks for being over weight limits. But the power of the grey lobby got the rules aligned nationally quick smart didn't they...

Might I suggest you write to your state Transport Minister and ask him the question - why doesn't SA adhere to the NCOP (make it easy for him - give him the reference to VSB14) :). But then don't play so nice....make sure you copy the letter (or even email - same same) to the Shadow Minister.

Politicians, as we all know, love nothing more than embarrassing each other. And if the guy in office doesn't come back with a decent response, the guy in opposition should be all over him (her?) like a kitten on a spider asking why, if there is a national set of standards, should the SA tax payers be stumping up the funds to come up with a unique set of standards all of their own... When Gov'ts are running off at the mouth about reducing red tape, making life easier for people etc, time for them to put their money where their mouths are and actually do the deed. It is OUR money after all - it is OUR money that is paying THEIR wages - they should be doing what WE demand of them.
 
I went to the vic 4x4 show today and was talking to a person about suspesion mods and extended brake lines.
This person told me that extended brake lines have to get an engineers cert.
Does anyone now if this is true or not?
 
I went to the vic 4x4 show today and was talking to a person about suspesion mods and extended brake lines.
This person told me that extended brake lines have to get an engineers cert.
Does anyone now if this is true or not?

I don't think that is correct. I rang Pirtek first, they told me they weren't allowed to make brake lines, so I went to ABS brakes. I would have thought they would have known if it was illegal and not performed the job. Cost me $80 for the rears 100mm longer.

I think some of the stainless braided ones you see advertised don't have approval.
 
My understanding is that extended ones don't need approval but braided ones need approval (or maybe even cannot be approved, not sure sorry).
 
Thats another strange law, I have used braided lines on bikes for a few years. They are superior in every way. Give better stopping power (stop the brake lines swelling under pressure) give better feel and are more damage resistant. Its hard to follow the logic of the powers that be sometimes.
 
I stand corrected. Another old wives tale put out to pasture it would seem :)

I've had a look through VSB14 regarding brake modifications. There is nothing to say braided lines can't be used. They only make references to ensuring that brakes lines conform to relevant standards for brake line material. References to ADR's etc (which I followed up) and they make basically the same statements.

That covers the ACT as we apply VSB14 in its literal form.

NSW doesn't seem to explicitly ban them (but since I don't live there, I didn't dig very deep), and seeing as though it's Sunday night I've done enough research :)
 
In VIC, one used to be able to buy the Bundy Pipe to make your own lines, as we did when doing our V8 conversions,
but have been told in recent years the suppliers were not allowed to sell to joe public anymore.

Similar to, we used to be able to install our own LPG conversions but it is a nono now.

Would be for the sake of safety in both cases i suspect.
 
I distinctly recall being told that braided brake lines were against the law and I couldn't understand why either, because the braiding reduced swelling, allowing a more direct feel. I wanted to put these on my CB 900 Bol D'Or which was getting a little long in the tooth and was told I couldn't. Had to replace with Honda gear.

This is one particular area of the law that I don't understand at all.

As for longer brake lines, there is an issue with hydraulic systems over a certain length (pressure drop-off due to hose expansion), but there should be no issues that relate to hose diameter, master cylinder piston size, brake fluid reservoir capacity ... because regardless of how long the hose is, you press the brake pedal and the calipers still move the same, small amount.

I might research the braided line issue later.
 
My Merc has stainless braided lines factory fitted. Maybe the rules have changed over the years with regard to replacement items? Who knows... Anyway, from what I can read (in the ACT) there is nothing stopping people installing braided lines as long as they are of quality manufacture (up to applicable standards) and the line material is of sufficient quality (up to applicable standards). Perhaps someone with more direct knowledge/experience can advise?
 
You can use stainless braided lines in Vic but they need to meet the appropriate ADR and generally will be marked as such. The only reasonable explanation I have seen as to why they have not been kosher is that the stainless braid firstly makes inspection difficult if the line deteriorates internally and secondly means that you can not visually see what the inner is made of. Funny enough older Datsus used to have braided lines too, but it was a fabric braid.

You can also generally get bundy tube as well. I have bought some recently to alter things on my race car (Must get some more, I have a factory rigid line that runs only a couple of inches from the exhaust housing of the turbo)
 
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You may well still get hold of Bundy pipe if you know the right people,

but one reason why they put a stop to selling to joe public here was that too many were not using the correct flaring tool and putting a "Double Flare" at the ends as is needed on brake lines,.

and with the flex/braided line,
it is the the unknown quality of the end fittings and crimping,
and the many types/ quality/composition of hose on the market that some are not up to the design standards set in this country,states.

Remember the braking system of a vehicle is an important component of the vehicle package and as such should have tough standards.
 
You will hear no disagreement from me there. I have seen some poor jobs even on race cars over the years, including single flares failing on the track. Done by people who should have known better too..

Mind you I think a lot of new braking systems are not up to scratch. I have seriously thought about getting a US market master cylinder for my R51 Pathfinder as they have a larger bore cylinder on at least one model. That would reduce the R51 (And I assume D40 though I have not driven one) endemic problem of a disconcertingly soft and long travelling brake pedal. At 130,000km or so I had to replace the master cylinder on mine as it just would not produce a decent pedal. You could literally push it to the floor with assistance of the booster (And it is over boosted which makes it feel even worse, if you hold constant pressure it will slowly travel nearly to the floor before it reaches some kind of equilibrium) Even the new master only produces what I would describe as a barely acceptable pedal. I broke into the old one (Which is a non serviceable item) and the seals had no contact pressure left onto the cylinder bore. the front piston literally fell out onto my hand when I tipped it up!

I am just barely living with it now but it my biggest gripe with the car. Brakes should be modulated with pressure on the pedal, not by pushing it down another half an inch. It is very disconcerting to have to make a panic stop when towing and have the pedal basically on the floor before you get it pulled up, all the while never actually producing what you would describe as a strong stop. I might sell the car over it yet. My D22 has a far better feeling pedal.
 
It is very disconcerting to have to make a panic stop when towing and have the pedal basically on the floor before you get it pulled up, all the while never actually producing what you would describe as a strong stop.

I don't know what you're hauling when this happens, but my Navara + 1.8T van comes to a halt nicely when needed. Having 4 electric brakes and a decent proportional brake controller (properly adjusted) does help, I'll admit, but even when I turn down the braking force on the van, the Navara still brings the thing to a halt nicely.

It does suffer on hot days with repeated hard stops, so the pads aren't immune to fading. I manage that by driving more sedately and have no trouble at all.

Now, if others have similar experience, maybe your braking system has a problem that needs attention, like a fault in the hydraulic lines somewhere (eg swelling hoses in the wheel wells, or an ABS fault)? Since the ABS is designed to release the brakes, what if there's a small amount of debris caught in the valve and it's leaving it the slightest amount open, affording you the opportunity to depress that pedal all the way?

My pedal never, ever gets close to the floor. Not even under the hardest braking.
 
I've had 30 tonne of logs, locked trailer brakes a sloppy dirt track and the three rear axles on the drivers side clearly visible in the right hand mirrors and not visible in the left hand mirrors. Luckily is was only at 40ks on a road used only by log trucks and I was able pull the tractor up before the trailer got really out of hand but still that was disconcerting and I'll take your foot to the floor pedal any day over that.
 
Lol, so would I I think.

Old Tony, of course there is a fairly major brake difference from the D40 to the R51 in that the Nav has drums on the rear. A long and mushy pedal on the R51 is a fairly common complaint. I have actually been thinking about replacing all the rubber lines with (Obviously ADR approved) stainless braid ones to help improve the feel of it. The panic stop would have been with about 1800kg behind it, electric brakes with proportional controller, adjusted so they very nearly lock the trailer brakes (Only two braked wheels though)

my only real bugbears with the R51 are that I hate the feel of the brakes, it has far more bump steer than it should (Presumably so do D40 utes) and the YD25 is pretty intrusive. mine is an early build car, I beleive they have increased the sound deadening in later ones.

My other gripe is that some spare parts prices are literally obscene. the new master cylinder cost around $1100 trade cost price and was as bare as a babies bum (As in a bare master cylinder, no reservoir, no low fluid switch, no VDC pressure transducer. Nothing but a new seal between it and the booster) The VDC version is around $300 more than the non VDC version and the difference is an extra port in the cylinder to screw the transducer into.
 
My other gripe is that some spare parts prices are literally obscene.

I don't really think thats a Nissan problem I think it's across the board with all manufacturers. Those who know seek after market parts, those who don't know or don't care about the cost go back to the dealer and pay the stupid prices therefore they think they can justify it.

There must be more people out there that just accept the high cost than there is looking elsewhere or surely dealers would start dropping their prices in order to actually sell the stuff they have. Down here there is also a lot of people out there on novated leases where they don't have a choice and have to choose the dealer which further helps the dealers justify their high prices.
 

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