John Brett

John is a professional engineer with 50 years experience.

John has designed and built many cars, trucks, and vehicle assembly facilities.

John has worked on design of roads, bridges, cranes, transmission towers, and buildings, and operation, maintenance and upgrade of hydro and gas turbine power stations.

John was a LVV Certifier for 13 years. John has long been a whistle-blower, expressing the view that the LVV system is dangerously deficient. John's authority was revoked in December 2012.

John rides a 1992 Yamaha FJ1200ABS, and is also a keen road and off road cyclist.


“The LVVTA has brought it to my attention that statements I have made in relation to it and its employees may have been perceived as defamatory.

I sincerely regret that and apologise for any harm caused. I have taken down the statements identified by the LVVTA of concern to it.

I have strong views about the low volume vehicle certification process and intend in the future to direct my energies into the public inquiry now being held in relation to it.”

John Brett 7th October 2015


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Wheel Spacers FAQ’s

Wheel Spacers are the subject we are most common asked about.
The rules are all on the LVVTA website in the Wheels and Tyre Standard 2005-00


Non-Legal spacers


SPACERS need to be ‘Hub Centric’ and ‘Wheel-Centric’, or a centering ring has to be made to centralise the wheel and the spacer.
This means in practice, that wheel spacers will need to be custom-made to suit the specific vehicle and wheel combination.
Also you will probably need to fit longer wheel studs to keep the required thread engagement of the nuts.

ADAPTORS are Centered on the hub by the tapered nuts hulding them onto the hub. The wheel is then Centered on the adaptor by the tapered nuts holding the wheel on.
Centering spigots for the adaptor or the wheel are not required. (See LVV Standard 2005-00)


The LVV Standard says that adaptors ‘are manufactured by someone competent and experienced in the type of work undertaken, who has the necessary equipment to carry out the manufacturing correctly’
We do not know many people in Japan, or China, and find this clause to be unhelpful.
Instead we:-

1 Do a material hardness test to determine the likely material. Most adaptors are T6 Aluminium Alloy, which has a hardness of 40 to 45 Rockwell C. We do NOT want to accidentally certify any adaptors made of soft alloy, zinc castings or shite metal!!

2 Do a simple stress calculation (using a spreadsheet template) to determine the shear stress between the bolts, and the shear under the bolt head. The adaptor should be equal in strength to the wheel studs. We find that adaptors THINNER than about 12mm are usually over-stressed.

Spacers are not permitted to be more than 20 mm
Adaptors are not permitted to be more than 27 mm,
Most adaptors are to compensate for wheels with wrong offset offset, (not to effect a change in stud pattern).

Wheels flying off can kill people (it has happened more than once)
Wheels flying off can make controlling the vehicle a tad tricky, especially since it is likely to happen under hard cornering.
People getting killed is clearly to be avoided- as is getting sent to jail for manslaughter.

Failed Wheel Adaptor

Failed Wheel Adaptor


Additional information-
Tyre and rim sizes-
The LVVTA compatibilty chart can be found here

This is based on the best information available at the time the chart was written- however a Tyre manufacturers reccomendation takes preference- so check with the tyre manufacturer if you want to use a combination outside these guidelines.

Hope this clears up any confusion, and helps you to get it right before going for your Cert.

164 comments to Wheel Spacers FAQ’s

  • Robert

    I’m looking at getting some 20mm hub centric bolt on spacers for a 93 vr commodore just for the rear wheels as they tuck under the body, would like them to sit out further basically. The spacers I’m looking at are a high strength alloy, what are my options , will I need a cert for these or not cheers

  • johnbrett

    Hi Robert- Yes the vehicle will need to be LVV Certified

  • Volkan edali

    Hi, john.
    I recently bought new wheels for my 1982 Toyota land cruiser bj42, and when I put them on , the front ones rubbed against the tie rod ends so I went and bought 25mm thick 6 stud high quality aliminium adapters which solved the problem nicely, now I need to re-register the car as the rego has lapsed, should I take it to vtnz with the spacers on or without them(with original wheels), do I need lvvt for this? would they do the lvvt at vtnz at the same time, ? how much would lvvt cost if I need to do it separately? Also do I need to get wheel alignment done after installing them? Thanks any help would be appreciated


  • johnbrett

    Hi- You will need a LVV Certification for the wheel adaptors. This can only be done by a LVV Certifier, not by VTNZ. I recommend that you get the vehicle on the road with standard wheels first, get your compliance done by VTNZ if convenient. THEN to fit the new wheels and adaptors and arrange for LVV Certification. There is no requirement for a wheel alignment for a LVV Cert for wheels and adaptors, however if the vehicle has been off the road, I recommend an alignment anyway.
    Hope this helps John

  • Ben Yates

    I want the wide stance look on my Subaru but only seem to find the rims for 5×114.3 in the right offset not 5×100 can I use adapters I know I will have to extend the guards and I am doing this but will this get certed. Thanks

  • johnbrett

    Hi Ben- I don’t understand what you mean about 5 x 114.3 and 5 x 100, could you pls explain? You will need an LVV Cert for adaptors. Remember that the maximum thickness allowed is 27 mm, also that too much offset can negatively affect the steering and handling. Hope this helps, John

  • Ben Yates

    changing the stud pattern from 5×100 to 5×114.3 if I have to much offset how badly does it effect the handling does it make it more stiff due to leverage from the wheels being pushed out using 25mm

  • johnbrett

    Hi Ben- increasing the offset will make the steering heavier, and increase kick-back. It also loads up all of the suspension joints, making them wear quicker. It puts more leverage on the springs and dampers, making them appear softer. On most modern cars, tyre and wheel widening can be added on the INSIDE as well as the OUTSIDE, so that the offset is not increased. The advice of a GOOD wheel and tyre shop is worth having, they know what works for your car. Hope this helps, John

  • Ben Yates

    I think I will not use adapters just use offset but I’m using air suspension so that’s the weight issue solved but ball joints what would be a maximum in mm that would be recommended as being so low I will have ball joint issues any way but would like a little life oh and Anti Lift Kits which lower the control arm and steering tie rods so they are on a more normal angle to get rid of the excessive angle issue do they need to be certified or even legal in NZ.

  • johnbrett

    You have quite a list of modifications there! I think you need to arrange a site visit to go over it in detail. Regards


  • Ben Yates

    Where abouts are you located? keen to vist

  • johnbrett

    Would you please call us on 0800 LOWVOLUME (0800 569865) thanks, John

  • craig

    hi, i am also wanting to use adapters to change stud pattern, what info can you give me on this, is it legal, is it safe, will i need a cert aswell? cheers

  • johnbrett

    Hi Craig- you will need a Cert. It depends on the Certifier’s assessment as to whether it is legal. He will have to make sure that it is structurally safe, and that the vehicle drives OK

  • Arman

    Hi, I put on 3mm slip on spacers recently on the fronts so that my new wheels wouldn’t rub, they were rubbing on something so I needed to put on the spacers, I was just wondering would I need to cert the slip ons?

  • johnbrett

    Any spacers need certifying- and many are not suitable unsafe, and cannot be certed check out

  • jay burns

    Hi. Me and my gf bought some rims second hand for her 89 e30 bmw. They turned out to b the wrong offset but we liked them and were fairly cheap so decided to get bolt on spacers. We’ve run into a problem. The spacers we bought, though they were the right center bore size(57.1 for e30 bmw), the hub centric reccess is only 10mm where as the bmw hub lip is about 13mm so they dont seat against the brake hat properly. I was wondering if we could use 15mm (front) and 20mm (rear) slip on hub centric spacers and use extended wheel bolts instead? Cheers

  • johnbrett

    I suggest that you read, or the LVV Standards. There is no reason why front and rear spacers have to be same thickness, but have to meet the requirements. Cheers, John

  • mike

    hey john,I have recently put my 1985 audi coupe quattro through certification for mods to the brakes and abs and I want to put my OEM wheels back on the car,I put it through the process on some audi rims that are OEM as well but not the original ones. I have discovered that the original wheels don’t clear the new callipers without a hub centric 12mm spacer being used…the plate on the car says the rims are OEM . I really don’t want to have to get the whole lot re checked and re-certed but I suspect that’s what needs to happen to be legal huh?

    what is the process for this? will the certifiers just look at the wheels and the spacers and re stamp the plate for me,or will they re do the whole thing and look at everything else again?


  • johnbrett

    Hi Mike- Yes the car needs re-inspection, and a new LVV Plate. The whole car will be looked at, but only the changes will be Certified. Hope this helps, John

  • Dane

    Hi if i put 10mm spacers on the front to prevent tyre rub against the upper control arm, do i need to put rear spacers on as well? I tried to search for the information to no avail. cheers

  • johnbrett

    No- you do not have to put on rear spacers
    Thanks for your enquiry



  • Zach

    Hi, Wat mods can ido to my hilux ln106 without certification ? e.g how big wheel can i go, lifting etc.



  • johnbrett

    For wheels the WOF guide says than Certification is NOT required when-

    the wheels:

    – are of a known and reputable brand, and

    – would be considered an appropriate fitment for the vehicle type by the wheel manufacturer, and

    – are not modified, and

    – do not have spacers or adaptors fitted.

    the tyre tread:

    – does not protrude beyond the unmodified original body panels (including unmodified factory-fitted mudguard extensions), or

    – protrudes beyond the unmodified original body panels, but is covered by aftermarket or modified mudguard extensions or modified body panels, and the track width has increased by no more than 25mm from OE.

    Tyre size changes

    the tyres:

    – have an outer circumference that is no more than 5% greater than OE, and

    – are an appropriate selection for rim width, and

    – have tread that does not extend beyond the original or modified body panels or guard extension (see Figure 10-1-1).

    For suspension, this is all there is:
    Springs and shock absorbers

    the springs or shock absorbers are direct replacements, and
    replacement springs are contained within unmodified OE seats throughout full suspension travel, and
    replacement springs are self-retaining in their seats at full extension, without the use of non-standard devices such as wire-ties, straps, or external spring locators, and
    replacement springs have not been heated or cut, and
    springs and spring seats are not height adjustable by any means (unless OE), and
    replacement shock absorbers, including air-adjustable units, fit unmodified OE mountings, and
    suspension maintains sufficient travel for safe operation when fully laden, and
    suspension components maintain sufficient clearance from unmodified bumpstops when fully laden, and
    a minimum of 100mm ground clearance (unladen and without driver) exists below any part of the vehicle structure, or any steering, braking or suspension component2, and
    the normal relationship between front and rear suspension height is not unduly affected.

    2 Does not include such items as exhaust pipes and exterior body panels that do not contribute to the structural strength of the vehicle.

    Blocks for leaf springs to adjust their ride height (up or down)

    the suspension has not been raised by any other means, and
    the blocks are:

    – securely fitted, and

    – constructed from metal, and

    – designed for the purpose, and

    – firmly seated over not less than the OE seat area, and

    – not more than 50mm in height.

    Larger diameter anti-sway bar

    the bar is attached to unmodified OE mounting points.

    Addition of anti-sway bar

    no cutting, heating or welding to the vehicle structure or suspension components is involved in attachment of the bar.

    Suspension braces (strut tower braces)

    there are no structural changes to the body or suspension mounting points.

    Eccentric bolts/bushes for adjustability of wheel alignment (eg for camber correction in association with lowered suspensions)

    the bolts/bushes are:

    – designed as a means of correcting or improving wheel alignment; and

    – catalogued aftermarket items for that make and model of vehicle.

    There are many other things you can do which could be dangerous, but this is all I can give you from the book
    I hope this helps

  • Jon Louie Paul


    what kind of spacer can i use or the max size can use with out certification ?

    My car is a mazda Axela 23s.

  • johnbrett

    Hi Jon Louie
    ALL spacers need to be Certified, no exceptions
    Details on requirements for spacers and adaptors are on this site- at
    I hope this helps

    Regards John

  • julie

    Hi, I am wanting to get some 4-5 stud wheel adaptor spacers (they bolt on and convert 4 stud cars to 5 studs). They are made of T6061 Aluminium and hard anodized. Just wondering whether they would pass certification. They are hub centric.

  • johnbrett

    Hi Julie- They sound fine, so long as the thickness is more than about 12 mm. I would do a hardness test to check that the material is what you say and not some weak substitute, also run a stress analysis, which checks that a- the studs won’t pull thru, and b- that the adaptor won’t shear between the holes. But don’t worry about this, they are unlikely to fail unless you bought them from some dodgy chinese website. Hub- centric is good, wheel-centric is better, but the tapered nuts are considered enough to centralize the wheel. Hope this helps- John

  • Paul

    Hi John
    I have 25mm adapters fitted at the moment to have my tyres sit flush and am looking to get re-certified as a result (car is already certified).

    I really like to look and am considering getting different wheels so they sit the same (slightly wider wheels and different offset) without the spacers.

    My question really is whether this is a waste of money! The only reason I would do this is that I am concerned about the safety of the adapters. They are a reputable brand and are quality materials. About five times a year I do “playdays” on track but am by no means a race driver! Are adapters “safe”?



  • johnbrett

    Hi Paul- You do need to get the vehicle re-certified if you change wheels from what was on at the time of the Cert. For Adaptors, I do a material check, and stress calculations, however this is not required by the LVV Standards.

    Hope this helps


  • Connor

    Hey i want to convert 5×112 to 4×100 is it possible to certify adaptors that do this or is it not possible?

  • johnbrett

    Hi Connor
    There’s no reason why not. The usual considerations for adaptors apply, not too thin, made of decent material, not too much offset.

  • damien

    Arent wheel spacers the same as wheel adaptors? Or is a spacer same stud pattern on studs and holes. And adaptors from 4×100 to 4×114? If so why only 20mm for 1 and 27mm for the other? What is the difference? I dont understand. ….. also what grade studs and nuts are required? I have found some t6 aerospace alloy. 10.9 studs with grade 8 nuts. Is this legal in nz? Thanks

  • Jeremy

    Hi i am looking at getting some hun centric spacers for my vehicle which adapt the centre bore to allow for wider range of vehicles to be fitted. they are 20mm and slip on not bolt on are they able to be certified or are they a waste of money?

  • johnbrett

    The difference between Adaptors and spacers is explained on my page
    The LVV Standards don’t specify any grades, so according to LVVTA any sort of metal is OK
    When I was Certing I looked for a 6068 T6 Alloy, and ran a stress calculation to make sure they didn’t fail and shed a wheel.


  • Rob

    And are all these requirements equally applicable for light car trailers? i.e. the hub/wheel centric, widths, certification.
    Specifically the requirement for certification.
    “Land Transport Rule Tyres and Wheels 2001 Rule 32013”, would suggest yes.
    But the “In-service certification (WoF and CoF) – General trailers” “Section 7 Tyres, wheels and hubs – Reasons for Rejection” makes no mention of them.

  • johnbrett

    Hi Rob
    Low Volume Vehicle Certification does not apply to trailers.
    The In-Service Inspection (WOF) is here:,-wheels-and-hubs/tyres-and-wheels
    That’s all you have to meet.
    There are clearly a few un-regulated dangers with trailers!


  • Rob

    Thanks John – and no need to publish this comment and clutter the place up – just wanted to thank you for a great website with information that is actually useful and answering my question about trailers. Cheers Rob

  • Jarred

    Hi, am in the process of getting my car ready for cert, i will be going in with a 25mm adaptor fitted to make the offset better. If i was to change my wheels in the future to a better offset but not a different width, (keep same as on the cert plate) would cert been needed because i do not have spacers on the hubs anymore? thanks.

  • johnbrett

    Hi Jarred
    I assume you need a Cert for other things besides the wheels?
    If you do get a Cert, it will show the wheels (and any spacers or adaptors) fitted at the time of the Cert. If you then change the wheels, or remove spacers or adaptors, you will need a new Cert. It is quite hard to get a LVV Certifier in most towns, and getting expensive. So my advice is to do it once, the way you want it to stay.

  • jonathan

    Hi There

    Bit of a strange question but are center lock wheels road legal? For example a similar adapter/wheel set up you may see on an old Jaguar? I assume the adapter rules and regulations are the same as any other wheel spacer/adapter?


  • johnbrett

    Hi Jonathan- I can not find anything in the LVV Standards about these. I would not see any problem myself, so long as they were well made and installed. Now, the LVVTA appear to make decisions on an ad-hoc basis, so better to talk to them.
    Thanks for your query


  • Daniel

    Hi John, I have a B5 Audi A4 running 18×8 235/40 tyres. Due to the tyre spec and offset of the wheel i require 5mm slip on spacers. Currently have multi fit spacers which were a last resort to get the car running as the shop ran out of the correct spacers. I have ordered a pair of TORQ 5mm slip on spacers which are hub and stud centric (57.1) I was assured that these can be certified. Am I safe in thinking my car will pass? p.s this site is so helpful, its great keep up the good work.

    Thanks very much

  • johnbrett

    Hi Daniel

    Thanks for the kind comments
    You know that any spacer needs LVV Certification. The requirement is that the wheel has a method of centralizing it to the HUB, the wheel studs cannot do the job when there are two surfaces. So the spacer needs to be hub-centric AND wheel centric. Another way is to have a centering ring. The spacer needs to be attached when the wheel is removed, and the spacer has to be solid- no extra holes. Don’t forget longer studs, so you still have full length of thread engaged.
    Good luck finding a Certifier before January- I suggest you make sure your WOF has time to run before you fit the spacers!
    Hope this helps



  • martin

    hello i have some wire wheels that have knock off adapters eg a adapter that goes from 6 stud to the one large center nut from standard
    Am i alowed to add steel to the base of these adapters so there one pice like from the factory or fix a spacer plate to the hub is this legal because that is the only way to bolt up this design of wheel

  • johnbrett

    Hi Martin
    I gave the following advice recently to Jonathan on the same thing:
    “Hi Jonathan- I can not find anything in the LVV Standards about these. I would not see any problem myself, so long as they were well made and installed. Now, the LVVTA appear to make decisions on an ad-hoc basis, so better to talk to them.”
    Same advice applies-


    Thanks for your query

  • Antony

    Hi John

    When i bolt on the 20mm spacer the factory studs stick out past the spacer surface. The wheel sits on the studs rather than the spacer. The studs need to be shorter. Can i trim them with an angle grinder or do they need to be replaced with shorter ones?

  • johnbrett

    Hi Antony- There is no problem trimming the studs, just remember to replace them if you decide to remove the spacers (adaptors)


  • andrew

    Hi there. I’ve got an old c10 and am running spacers on my rims. I’m using shank style lug nuts so the rim is still bolted directly to the brake disc/hub meaning it is essentially stud centric and the spacers are machined to fit perfectly around the shank of the lug nut making them stud centric also. Will this pass a cert as is or will I still need to add a hubcentric ring? Cheers

  • johnbrett

    Hi Andrew
    No it will not comply- because A the standard requires hub centering when there are spacers, and B it puts bending loads in the wheel studs which CAN cause stud failures



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