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One
of the biggest improvements to the look of your beloved van is to add
some alloy wheels, as well as being lighter (supposedly!) and reducing
your vehicle weight they also dissipate heat away from your brakes better
than standard steel wheels which is useful as you'll find out once you've
gone down Porlock hill in Devon with a full load!! And more to the point
they make the van look a shed load better!
Wheel
data.
To understand better why some wheels fit and some don't read on.
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PCD
or pitch circle diameter. In lay mans terms its the bolt spacing,
its the diameter of the circle that you would get if you were to
draw an imaginary circle that would go through each bolt holes.
On a T3 the PCD is 112mm.
- Hub
bore
(or centre bore) the hole
in the middle of the wheel, this needs to be 66mm, any less and
your wheels won't fit over the wheel bearing cap on the front wheels.
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Wheel
dimensions
Factory wheels are
5 1/2Jx14, or 6x14 for the factory alloy wheels.This means the rim is 5 1/2 inches wide and 14 inches
in diameter.
Remember that wheel width is measured on the inside of the bead and to the face that can be seen with the tyre fitted.

- Wheel bolts/nuts
The thread size is M14x1.5, if you are fitting alloys then you will need longer bolts as the standard ones are too short for the thicker alloy wheel. There are several aftermarket sources for these. If fitting alloys 99% of the time you will need some form of longer bolt (or conversion stud) for the front and longer rear wheel studs.
Please be aware that there are 2 types of wheel nut/bolt seat styles in regular use.
Generally VW use the radiused seat style [top] along with Mercedes and Porsche, other manufacturers and the aftermarket tend to use the tapered style [bottom].
Before fitting please make sure you check your wheels that you intend to fit for what style of seat they have as although the wrong sort will fit they won't be right.
The purpose of the seat is to get the wheel to centre on the hub, incorrect seat types will damage the wheel and the wheel won't centre as it should.
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Radiused seat |
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Tapered seat |
Please note that T3's that left the factory with alloy wheel actually have tapered seats.
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Spacers.
Spacers should be used to correct the offset of the wheel you are fitting. VW spent a lot of time and money developing the suspension on the T3, all the steering geometry, wheel bearings etc. are all set up for standard wheels. If you vary from factory settings then you are likely to gain some strange handling characteristics and accelerated tyre wear.
The ET measurement found on a wheel is the distance in millimeters from the bolt face of the wheel to the centre line of the wheel. ET is an abbreviation of a German term laterally meaning "Back Spacing".
T3's that came from the factory with steel wheels have a ET of 39 while T3's that left the factory with alloy wheels came with a ET of 30.
So, in my eyes if you are fitting alternative wheels you should be aiming for anywhere between ET 30 and ET 39. When using a wheel that wasn't designed for the T3 then you are unlikely to get the correct ET, this can be remedied by the use of spacers.
e.g. if your wheel has a ET of 45 then the use of a 10mm spacer shim would reduce the effective ET to 35, which is in the middle of the range of factory wheel offsets and would be acceptable for use.
Wheels with a ET of less than 30 tend to stick out more and give the vehicle a feeling of not wanting to do much more than going in a straight line, wheel bearing load will be increased, steering will be heavy and the tyres will wear more on the inside edge and in my eyes are to be avoided.
Spacers are also used for clearance issues, if wide wheels are used then sometimes there is the chance of them fouling the suspension. You can't really go much more than 7.5" at the front without touching the suspension or having wheel arch clearance issues. Sometimes if you are adamant you need to fit a certain wheel the only way to do it would be to disregard what the ET is and use sufficient spacers to keep the wheel from touching the suspension, this is not ideal and not recommenced.
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Conversion studs.
Conversion studs are a real bonus for anyone who has ever tried to fit a wheel to the front of a T3 which has spacers fitted. To find the correct size please do a little homework first and measure the distance from the bottom of the wheel nut seat (narrow end) to the rear bolt face of the wheel.

Above is a cross section of a alloy wheel, to be able to order the correct conversion stud you will need to know the ET (offset) of the wheel plus the measurement from the bottom of the seat to the bolt face.
e.g..
ET 45
Depth of wheel bolt hole 10mm
So, with a ET of 45 you will need a 10mm spacer to bring the ET down to 35.
You have a 10 mm spacer plus the depth of the wheel bolt hole is 10mm giving you 20mm up to the bottom of the nut.
A wheel nut is generally around 25mm deep giving 45mm.
10 + 10 + 25 = 45
or
Spacer + bolt hole depth + 25 = conversion stud required
Therefore you will need a conversion stud that protrudes by 45mm from the disc.
Of course, it doesn't always work out nice like my little example but you get the idea, right?
So
what wheels fit?
- Well,
obviously VW put some alloy wheels on the Transporter from the factory,
as far as I'm aware 2 styles were available, some 5 spoke ones and
some multi hole ones. VW used radiused wheel bolt fittings for everything, except for the standard t3 alloys! so, if fitting these you will need either the correct fittings for the wheels or some taper seat nuts and bolts.
- Audi
A4, A6, A8, V8, S2, S4, S6 and recent Passat and Sharan and T4 have the required PCD
but the centre bore seems to be quite small at 57.1mm .ET35-45.
- Mercedes,
loads of choice here, obviously I can't go through all the types
available as there is absolutely loads. Be aware that some Mercs came with 12mm (M12) wheel fittings and not M14 wheel fittings required for the T3, so drilling out the wheel bolt holes is not an uncommon operation.
- Ford
Granada/Scorpio, believe it or not the humble grandad has something
good about it, its wheels, again loads of choice and there's some
nice 16" ones kicking around from the 24 valve Cosworth. ET 35-38.
- VAUXHALL
WHEELS DO NOT FIT! At all, ever, full stop, The PCD of Vauxhall
(Opel) wheels is 110mm, which is not 112mm!!. If these wheels are
fitted then they will bend the rear studs that are pressed into
the rear hub, If you then try to remove your rear brake drum you
will probably find that the studs are bent and your drum will not
come off.
And then there is the fact that your bending them in the
first place, this will not allow the wheels to centre properly on
the hub and in extreme cases the stud could snap, not good I'm sure
you will agree. No amount of drilling the holes out in the wheel
will fix it. And then there the front with a possibility of cross
threading the threaded holes in the brake disc as you try to wind
a bolt in on the piss. If you want to fit these wheels then you
will need adapters.
Other
things to consider.
Standard
steel wheels are designed obviously for their application, so you will
notice that between the bolt holes on the wheels there are some raised
areas, these are for clearance for the small bolts that locate the rear
brake drum. When fitting alloy wheels these locating bolts interfere
with the new wheel and cause it not to seat correctly. The M7 bolts
in question, with 11mm heads can safely be removed and left out as the
brake drum centers itself on the hub.
Locking
Wheel Nuts.
One
thing to watch out for is that once you have fitted some alloys you'll
want to protect them, now this is where the fun starts as VW for some
reason put wheel bolts on the front of the van and nuts to the rear
which meant to you that you have to buy 2 sets of locking wheels nuts/bolts
and carry 2 keys, or another way of doing it is to fit "Conversion
studs" which are a little like exhaust studs, having 2 threaded
portions and a unthreaded section. The conversion stud is screwed into
the front brake disc and converts it into having "sticky outy"
studs at the front giving 2 bonuses, one that wheel fitting is much
easier and 2 that you can just buy locking wheel nuts instead of 2 sets!
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Appliance
turbo vanes, as seen on the A-team van and here on Nigel's Subaru
powered twin door bus. |
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BRM's,
at last a vehicle that suits these wheels, been around for years
looking crap on beetles. |
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Porsche
of some sort |
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Porsche
design 90's. |
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EMPI
5's, dead cheap, loads to choose from, as found on rusting bay
window vans whose owners are more bothered about bolting shiny
stuff onto their beloved rather that welding the holes up. |
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Porsche
Cup 1's |
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Original
VW Transporter wheel. |
Also
see this page here for a list of some wheel
data of wheels that fit T3's and what you have to do to get them on!
Below
you will find a Tyre size comparer thingy, the top line is set to standard
VW T3 - Type25 tyre size, put your new Tyre size in the bottom row and
this clever little gadget will work out the difference in rolling radius,
ideal to work out how your gearing will be affected or how to work out
how fast you are actually going as your Speedo is lying to you!
A
full range of wheel nuts, bolts, studs, spacers and adapters can be
purchased from Brickwerks
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