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Choosing wheels and tyres for your T4 is not as straight forward as you may think. Early in the T4's life it quickly earned a reputation as a tyre eater so, unlike cars, important consideration must be made to weight - not only the unladen or kerbside weight, but also to the maximum weight that the vehicle is designed to carry, known as the Gross Vehicle Weight and Train Weight (vehicle and trailer combined).

All the data below is T4 specific - I have weeded out all non relevent car data - yet the fundamentals also apply to the somewhat heavier T5.

Unladen Weights Compared

Generally, due to extra safety equipment, additional body strength and emissions equipment, the T4 is considerably heavier than the T3 and the T2 that preceeded it.
  • T4a Vans start at 1445kg (T3 = 1395kg / Type 2b = 1197kg 2634lbs)
  • T4a Caravelles start at 1505kg (T3 = 1510kg / Type2b = 1333kg 2932lbs)
  • T4b Vans start at 1505kg
  • T4b Caravelles start at 1780kg
  • T5 Vans start at 1795kg
  • T5 Caravelles start at 2056kg
Like for like, a T4 is somewhat lighter than it's T5 equivalent - yet both compare favourably with large cars. Indeed, the current crop of MPV's come close to matching these vital statistics - particularly the T4 800 and 888 Specials (to recap - the maximum fully loaded weight that the vehicle is designed to cope with - Train Weight includes a trailer).

However, 185R14 reinforced radial car tyres may have been the tyre of choice for the T2 Microbus and T3 Bus and Caravelle, they certainly are not recommended for the T4a Caravelle, VW opting for 6 or 8 ply commercially rated tyres for early T4a Vans and Caravelles, as fitted to the larger engined T3 and T2 Commercials (lesser versions of which had crossply tyres - remember them, anyone?).

Tyre Markings

Popular standard T4 tyre sizes start at 185R14C 99/97 P for smaller engined T4a's (up to 1995) and 195/70R15C 102T for the larger engined T4a's and lesser T4b's, but what do the numbers mean?

  • 185 and 195 refer to the width of the tyre tread in millimeters. This may not be as exact as you may think - some tyres of any given size look (and are) physically wider than others - by as much as 20mm in some cases!!!
  • 70 refers to the height of the tyre sidewall as a ratio of the tread width, hence the term aspect ratio meaning that in this example the sidewall height is 70% of the width of the tread.
185R14 tyres do not have a figure for the aspect ratio. In such cases the sidewall height is 80% or 82% of the tread width.

Tyres with a lower aspect ratio, known as low profile tyres, have less bump absorbance in them, generally giving a firmer ride but able to tolerate higher cornering forces giving crisper handling because they flex less. However, this lack of shock absorbancy from any low profile tyre can cause a variety of rim damage - often on the inside of the wheel caused by certain traffic calming measures and pot holes, naturally.

Fitting lower (or higher) profile tyres without any consideration to the tyre tread width will have an adverse affect on gearing because the Overall Diameter of the tyre will be different, thus affecting in-gear speed, acceleration and fuel economy.

Rule of thumb - a greater Overall Diameter will give a higher in-gear speed, quieter cruising, but slower acceleration, all contributing to superior fuel economy and lower CO2 emissions.

The range of Overall Diameters suitable for any T4 without having a dramatic effect on the speedometer reading (i.e without going beyond a 10% maximum speedo accuracy tolerance, as required by law) is between 648mm (25.5") to 687mm (27").

  • R refers to a radial ply tyre. (Crossply tyres are generally regarded as inferior and are no longer readily available.)
  • 15 refers to the wheel diameter where the tyre bead sits on the rim in inches.
  • C stands for Commercial or Van tyre which tend to have six or eight additional plies in the sidewall to cope with full loads. The tread pattern tends to be spaced wider and deeper than a car tyre and the tyre compound tends to be harder wearing, all combining to give longer service life, at the expense of ride comfort.
  • 102 refers to the Load Index which is the most important consideration when purchasing your tyres. This relates to the plated axle weight that is shown on the Vehicle Identification Number (VIN) plate found either on the driver’s door pillar or bonnet slam panel of your Caravelle, Eurovan or Transporter. This has particular relevance to the T4 because of the loads they are capable of carrying and it is crucial for safety - and road holding.
The figures on the VIN plate listed below the 17 digit chassis number refer to the maximum permissible weights for that vehicle and are as follows:
  • Gross Vehicle Weight - the unladen weight of the vehicle, which includes 10litres of fuel and all levels topped up (but not the driver) and it's maximum payload (including the driver and a full tank of fuel).
  • Gross Train Weight - the overall allowable weight of the fully loaded vehicle and trailer.
  • Front Axle Weight - the maximum allowable weight bearing on the front wheels.
  • Rear Axle Weight - the maximum allowable weight bearing on the rear wheels.
The Load Index ratings - as published in T4 literature - that relate to T4 axle weights are:
  • 96 = 710kg per tyre
  • 97 = 730kg per tyre
  • 99 = 775kg per tyre
  • 102 = 850kg per tyre
  • 104 = 900kg per tyre
The above list refers to Load Index for the tyre sizes that VW recommend for the T4 - 96 being the lowest value given by VW. All of these recommendations come from extensive testing by VW, the tyre manufactures and bodies independent of the makers who verify their work.

Please take note that the LI value does relate to the overall axle weight (see T4 Axle Weights - A Summary) - VW guidelines to specialist coachbuilders allow for a +/- of 40kg on either corner; i.e an axle weight of 1500kg can be 750kg/750kg or 710kg/790kg so long as the overall weight remains at 1500kg.

A safety margin is necessary for weight transfer during cornering from bodyroll, and dive under braking especially in emergency situations. In these situations the majority of the van's mass is forced onto the outside front wheel, hence the need for a load valve on the rear brakes to stop them from locking when mass is thrown forward.

Having already mentioned that some MPV's (namely, the Touran) and Car Derived Vans (the Touran based Caddy) compare closely to the T4's vital statistics, some T4 owners have fitted 94 and 95 rated Extra Load tyres. It is worth noting that early Sharan's are fitted with 95 XL rated tyres and later examples come with 97 XL tyres (albeit of a lower profile that will upset the T4's gearing beyond the 10% speedo tolerance)...

  • 94 = 670kg per tyre
  • 95 = 690kg per tyre
The latest 3C Passat has a 17" 97 XL tyre that fits the bill.

  • T refers to the speed rating
Speed ratings that apply to the T4 are as follows:

Reinforced Winter Tyres
  • Q = 160km/h / 99.4mph
  • R = 150km/h / 105.6mph
Summer or All Season (Mud and Snow - M&S) Tyres
  • N = 140km/h / 87.0mph
  • P = 150km/h / 93.2mph
  • S = 180km/h / 111.8mph
  • T = 190km/h / 118.1mph
  • H = 210km/h / 130.5mph
Larger sized Summer or All Season Tyres
  • V = 240km/h / 149.1mph
  • W = 270km/h / 167.8mph
  • Y = 300km/h / 186.4mph
  • VR = 210+km/h / 130+mph
  • ZR = 240+km/h / 150+mph
Reinforced or Extra Load tyres tend to be fitted to larger cars and Multi Purpose Vehicles (MPV's).

Where normal car tyres have one or two plies (structural layers) in the sidewall, these RF or XL tyres have two, three or four additional structural plies to cope with extra weight, maintaining stability without compromising on ride comfort too much.

Being car tyres, their tread patterns tend to be more tightly spaced and shallower than van tyres and the rubber compounds are not as hard wearing, so they do not last as long. Expect roughly half the service life of a car tyre over a van tyre, but with huge benefits in ride comfort.

Tyre Summary

When considering tyres for standard wheels, van tyres are naturally the ones to choose, but when contemplating oversized alloy wheels van tyres of the required size may not be available.

Car tyres may be the only size choice available, so it is important to choose a car tyre that will handle the T4's weight - that is adequately load rated and ideally marked as Reinforced or Extra Load.

Please refer to Standard Tyre and Wheel Sizes for a full list of compatible standard T4 tyre sizes and Non Standard Tyre and Wheel Sizes for a list of sizes that don't interfere too much with the speedo reading.
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