Volkswagen 1 -ton van
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by A. J. P. Wilding, AM1MechE, MIRTE
FEW light commercial vehicles have had a career of 17 years without noticeable changes in the body. But such was the record of the Volkswagen van until last August when the latest version was introduced with a redesigned front end, considerable improvements in the cab and various mechanical changes. Even now the rear of the 1-tanner is hard to distinguish from that of its predecessor and at the front there is still an unmistakable likeness.
Inside the cab, though, the situation is quite different. The standard of trim and fittings has been improved a good deal and forward visibility and access to the cab are also better than before. Mechanical changes include the fitting of the 1,600 c.c. horizontally opposed four-cylinder petrol engine developed for the VW car and a revision to the design of all-independent suspension to give better road-holding characteristics.
Use of the 1,600 c.c., 47 bhp net engine instead of the 1,493 c.c. 43 bhp net unit was not expected to result in radical differences in performance or fuel consumption on a test of the latest design; there was no change in the transmission. A test of the previous model was reported in COMMERCIAL MOTOR on 21 April 1967, and similar hill-climb and acceleration times were recorded on this test.
The new engine gave slightly worse fuel consumption when running non-stop and when four stops a mile were made the figures were about 15 per cent worse. Good results were obtained on brake tests when the van showed excellent stability but on the debit side there was some tendency to wander when driving fast in blustery conditions in both the laden and unladen condition; there was a slight feeling of "deadness" in the steering. While conditions for the driver are greatly improved in the new design selection of 1st or 2nd gear was not an easy job on the vehicle supplied for test and there were occasions when it was not possible to select either of these ratios when stationary without a good deal of effort.
The tendency to wander referred to was surprising as the suspension design at both front and rear was changed for the new model. This was aimed primarily at improving road-holding and on this score the van could not be faulted. It handled extremely well when on corners or bends taken fairly fast in any load condition. The van was only prone to "wander" when strong gusts of wind hit side on.
Volkswagen recommends an increase in pressure at the rear tyres only when the van is loaded, even though the front and rear wheels carry an equal share of the gross weight when the payload is evenly placed over the lower section of the floor. This is relevant because it is not practicable to have anything on the rear raised part unless the load consists of bulky items which fill all available space. There is no restriction to things on the raised part coming forward and when I put 3cwt of load there to get the recommended front and rear weight limits the lot came crashing off at the first light-brake application. In the circumstances, if the pressure in the front tyres can be the same with and without payload, raising that in the rears is not likely to affect straight-line steering.
There has been a radical change in the design of rear suspension and drive to the rear wheels for the latest model. Earlier Volkswagen vans had a swing-axle layout but now the drive is through doublejointed shafts with the rear wheels on a three-point trailing link. The links on each side consist of a longitudinal plate that is linked with the torsion bar, and a diagonal control arm pivoted on the frame cross tube. With this layout the lateral forces which formerly acted on the gearbox are now taken up by the diagonal links and transmitted to the frame. An advantage to the design is said to be a very slight but intentional variation in rear wheel track and camber over the range of upward movement of the wheels. Rear-wheel camber is slightly negative when unladen and increases by a small amount as the wheel moves up as does the toe-in.
Front suspension on the van is now basically the same as on the VW 1600 car. There are two transverse torsion bars which are connected to the stub-axle assemblies by pairs of parallel trailing links. A torsion-bar stabilizer is bolted to the lower links to reduce roll when cornering and the upper ball joints can be adjusted to set the camber and castor angles.
When loaded with 19.5cwt of 561b weights, my equipment and myself, the van grossed exactly the designed figure. As already pointed out the load had to be placed on the lower section of fl oor and this resulted in a slight overload of the front wheels. The fuel consumption tests were carried out on a stretch of A6 north of Barton-in-the-Clay, consisting of a six-mile out-and-return run in each case. On the tests where stops were made each was of 15sec duration when the engine was left idling and the average speeds quoted take into account running time only.
Figures obtained are comparable with those on the test with the previous design early last year, but it is notable that a bigger drop in consumption occurred on the tests where stops were made. It appears that the 1,600 c.c. engine will use more fuel when driven hard than the 1,500 c.c. unit. There was a slight improvement in acceleration times; about what would be expected with the increase in power output.
No high-speed fuel consumption test was carried out because of extremely blustery conditions on the motorway but when on MI late in the evening when the wind had dropped slightly, it was possible to get the van to its maximum speed of 65 mph for long enough to check this point; it was still not considered completely safe to drive continuously at over 50 mph because of the wind. Maximum speeds in the intermediate gears were checked on the motorway and found to be 22, 37 and 55 mph. These speeds take into account a speedometer inaccuracy of two per cent at 40 mph and three at 50 mph. The speedometer was accurate at 30 mph. Brake tests were accompanied by a fair amount of wheel locking as is usual with vans in this category. Load transfer did not result in there being a greater degree of locking at the rear but the Volkswagen front brakes have a greater width (and area) than the rear which takes into account the fact that the greater effort is needed at the front with a vehicle of this design. On the handbrake tests the rear wheels locked almost immediately after the brakes were applied but even so the good figure of 36 per cent was obtained on the Tapley meter. Tapley meter readings on the footbrake tests were 87 per cent from 20 mph and 86 per cent from 30 mph.
The Volkswagen also performed very well on Bison hill. The time for the maximum-power climb was reasonably good and the fade test ended with the brakes still giving a good efficiency figure. Restarts in first and reverse on the steepest section of Bison were made without fuss and the handbrake held the vehicle easily facing up and down the slope.
The van supplied for the test was the version without a bulkhead behind the driver. A halfor full-height bulkhead can be specified and in both these cases there is a two-man passenger seat instead of individual single seats. Whereas the version giving access to the body was previously an extra there is now a charge when the closed-off driving area is specified.
As previous VW vans tested by CM have had the division between the cab and body, the latest was noticeably noisier to drive.
When there is not a bulkhead to keep the noise out some form of insulation below the section of raised floor over the engine would be an advantage.
It would also be worthwhile having a higher output heater with the "open" version. During the time I had the van temperatures were around freezing point and I found that even at the end of a 20-mile run there was insufficient output to get the interior sufficiently warm for comfort. In fact, I seemed to be surrounded by draughts and could not feel any effect from the heater outlet even though it was only 9in. away from my legs.
These points and the difficult gear changing apart, this Volkswagen was a much more pleasant vehicle to drive than the previous one. Visibility is considerably improved through the changes, access is much easier and the seats more comfortable; an additional feature is that the angle of the backrest can be adjusted.
Another difference between this and the 1967 van tested was that instead of hinged doors on the nearside of the body it had a sliding side door; the sliding gear and locking mechanism worked very well. A big advantage with the Volkswagen is a very convenient loading height to the main part of the floor and with side loading, placing goods in the body from the pavement is easy.
As mentioned in the previous test report access to the engine for maintenance is not ideal. The only way to reach the power unit is through the hinged flap at the rear and as I found when fitting up the fuel-test equipment, working on the engine can be awkward. I see no reason why an access-flap cannot be built into the floor section above the compartment.
As tested the Volkswagen 1-ton van has a list price of £790. A full-height bulkhead between the driving area and the body adds £9 12s 6d and a division halfway up adds £5 5s.