GOOD YEAR FOR ROAD TESTS
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A review by the Technical Editor of tests carried out in the past year
THE past year has been reasonably good for COMMERCIAL MOTOR road-test staff with 23 vehicles having been reported on. This does not equal the best years when it is possible to have around 30 test reports published but the number must depend on manufacturers making vehicles available and it is not through want of trying that the list is not longer. We have been fortunate in having some of the more important models not previously tested made available to us and in this category are a number of chassis for the new maximum weights such as the Commer Maxiload, Dennis Maxim and Albion Super Clydesdale four-wheelers for 16 tons gross and Atkinson and Leyland 30-ton gross tractive units. In addition a Mack tractive unit was tested at 32 tong
gross and the latest entrants to the UK market, Magirus-Deutz were represented by a six-wheeler for 22 tons and a tractive unit for 30 tons g.t.w.
It will be seen that this year the splitting up of the vehicles into the various categories has been modified, as far as goods vehicles are concerned. All the sections are now related to load-carrying capacity of the models and instead of the multi-wheelers being grouped together, tables and charts for 10 to 14 tons load and over 14 tons load are included. In charts 4 and 5, weights quoted refer to gross rating. Vehicles have been tested in all categories, generally in equal numbers, but with a preponderance of heavy vehicles and only one in the lightest section. The latter is due to the fact that there have been few changes in light van models during the year and apart from one 5 cwt. van introduced recently, all models in this category currently available in the UK have previously been subjected to road tests.
The heaviest vehicle covered in this summary is the Mack /Northern 32-tongross artic and the smallest the Ford Trahsit 17 cwt. van. Between these two there are the normal-haulage models, a fire appliance, a light cross-country vehicle, two off-the-road trucks and three single-decker passenger models.
Introduction of the Transit on October 8, 1965 by the Ford Motor Co. represented a considerable step forward by the company towards standardization of body and cab designs, at the same time as giving operators
: widest possible choice of mechanical nponents. With the Transit range which .ends from 12 cwt. to 35 cwt. capacity and D Series of trucks which go from 2 tons id capacity to a tractive unit for operation 18 tons gross, Ford has increased the mber of actual models available and at the ne time retained only two basic ranges. An interesting feature of the Transit is the 3 of a V 4 power unit for petrol-engined assis and although the Transit tested )ssed 3.5 cwt. more than its predecessor, Thames 15 cwt. van, acceleration and 31 consumption figures were only slightly low those achieved when that model was led. Braking results were also very good d steering and suspension were found to commendable. One of the Ford D Series chassis appears in the next higher category-goods chassis for 2 to 6 ton loads-this being the D300. A 10 ft. wheelbase version was tested and this had the standard 14 ft. 3 in. long dropside body. Type numbers of the D Series indicate nominal payload in tons (the first figure) and grossing 6 tons a payload of 2 tons 19 cwt. was carried on the test. Fuel consumption figures were extremely good for a vehicle carrying this weight and brake figures returned were also above average. It was felt, however, that the axle ratio chosen for the test vehicle was a little on the high side-5.29 to 1-and that a ratio nearer to 6 to 1 would have made the vehicle more suitable for local-delivery work. Acceleration tests proved that the vehicle was no
sluggard, though, and with the high degree of comfort and low platform height made
possible with the 7.00-16 tyres fitted, it was felt that the D300 offered more than many vehicles in its class.
The second vehicle in this category with a load capacity of 3 tons was the Scammell Townsman, a completely different type of vehicle this being the latest version of the Scammell Mechanical Horse three-wheeler tractive unit. One of the most important changes in this model over its predecessor is a completely re-styled cab which was found to give increased comfort to the driver. From a general performance point of view the Townsman was found to be very good but poor braking was a black mark against the vehicle tested. This could have been due to the fact that the outfit had completed a very low mileage before the test. It was interesting that although carrying almost the same payload, the outfit grossed nearly half a ton less than the Ford D300.
Good general performance Completing the 2 to 6 tons load section is the Bedford KD 5-tonner which although not a new model was found to give as good a general performance as most recently introduced goods models. Excellent braking and acceleration were features of the vehicle tested and these were the cause of some trouble at the start of the tests. The test load moved forwards and caused damage to the body headboard on the brake tests and on the subsequent acceleration tests there was such a good "start oft' that they all shot back and in so doing put so much load on to the transmission that the differential pinion bearing outer track was burst. Another good point about the vehicle was fuel consumption and the standard of comfort for the driver was found to be very high.
Moving up the weight scale we have four vehicles in the 6 to 10 tons gross category and the two chassis from the BMC FJ range, the Morris 7-tonner and Austin 8-tonner make for interesting comparisons. Outwardly the only difference between these two versions of BMC's latest range is the tyre equipment, 9.00-20 on the 8-tonner as against 8.25-20 on the 7-tonner, but the two chassis tested had different wheelbase dimensions. The 7-tonner was tested in two forms, first with the standard direct-drivetop gearbox and then with the optional overdrive-top unit. The 8-tonner was tested only with the standard direct-top gearbox and as expected, acceleration performance and hill climbing ability were reduced as compared with the 7-tonner. But there was little worsening of the fuel consumption results; in fact the 8-tonner gave better consumption on one run than the 7-tonner with the same gearbox. Both tests gave good results throughout, particularly in braking and the standard of driver comfort given in the BMC tilt cab is very high. There was an unfortunate failure of a part
in the rear axle of the 7-tonner on the test but this was found to be due to incorrect assembly (which cannot happen on current chassis) and more directly to over-stressing the unit on the hill climb test but apart from this the FJ tests went well and both vehicles were found very pleasant to drive.
Ford 0750
Coming between the two FJ chassis in nominal payload capacity but carrying about the same amount as the 7-tonner there is the Ford D750 which was tested as a tipper. Fuel consumption figures returned by the D750 were very good indeed as was the braking performance and from all other aspects, acceleration, general handling and driver comfort the design could not be faulted. As well as a normal road test, the Ford tipper was taken to a sandpit and when driven over the very rough roads in the area gave every indication that the design was well up to the standard required for this type of work.
Completing this section there is the Seddon 13:Four, another of the new models introduced at the 1964 Commercial Motor Show. The tests showed that this model can give good fuel consumption coupled with a lively performance. Handling also was a good point with light steering and wellplaced controls and the general "feel" of the brakes was excellent. But hopes for good braking figures were not realized, actual stopping distances being a little below present-day standards. Credit for the good fuel consumption was given to the Perkins 6.354 diesel fitted in the chassis as standard and this incidentally was the only test in the year of a chassis fitted with this very-highly regarded engine. Going up the payload scale once more we have the three I6-ton gross four-wheelers, all of which were introduced at the 1964 Show. The first one to be put through its paces was the Albion Super Clydesdale and this also gave the first opportunity to test a vehicle fitted with the Leyland Group Ergomatic tilt cab. The Super Clydesdale was developed from the previous Clydesdale 14 ton gross model and as the Leyland 0.400 engine was retained, Albion has reduced the power-to-weight ratio against the general trend to increase this figure on new models. In the circumstances it was a little disappointing that the high standard of luxury given to the driver in the new cab was not matched to a more lively performance. Acceleration figures obtained were just about acceptable and the braking figures were reasonable. One strong point in favour of the Super Clydesdale was fuel consumption and the model was also praised for its suspension and general handling characteristics.
Commer Maxiload
When the Super Clydesdale was tested it was thought that the fuel consumption standard set by the chassis would be hard for other designs to reach. But this was fairly quickly disproved by the Commer Maxiload which returned some 9 per cent better. Introduction of the Maxiload marked the entry by Commer into the maximumweight four-wheeler field and the design was not found to be open to criticism on any point, except perhaps a fairly high first-step when entering the cab. A slight delay in air-pressure build-up did not allow braking figures to be as good as they should have been but the general standard of performance was high and the pattern of actual braking good.
The Dennis Maxim did not give such good figures for fuel consumption as the Maxiload—they were about 6 per cent worse—but these were still much better than were anticipated for a vehicle fitted with a Cummins lightweight V8 engine. With an output of 178 b.h.p. net from the power unit it was not surprising that the Maxim had a lively performance. This was well illustrated on the acceleration and hillclimbing tests and even though peak torque was not reached with the Cummins V8 until 1,750 r.p.m. there was a good pull away from 500 r.p.m. or so on the direct-drive runs. A high standard of comfort is provided in the Maxim cab and the model has very good brakes; in spite of wet roads good stopping distances were obtained.
MagirusDeutz
22-ton-gross six-wheeler
As usual, the highest number of vehicles appears in the highest-weight category and all except one-of these were artics operating at the latest maximum weights. The exception was the Magirus-Deutz 22-ton gross six-wheeler which was tested just as first deliveries of this make were due to be made in the UK by Magirus-Deutz (Concessionaires) Ltd. The Deutz air-cooled VIO engine in the test vehicle had an output of 235 b.h.p. net and not unnaturally, general performance was extremely high but fuel consumption was barely adequate. Good stopping distances were recorded in the brake tests in spite of a good deal of locking of the rear wheels and from a driving point of view the test vehicle could not be faulted.
The Magirus-Deutz six-wheeler tested was imported into the UK purely for demonstration purposes and was a left-hand drive chassis with sleeper cab. A tractive unit of the same make was tested with a Merriworth semi-trailer at 30-tons gross train weight and had right-hand drive with an earlier-design cab. This model was reported as being in good demand in the UK and the road test showed that fuel consumption was at a reasonable level, with performance and handling characteristics commendable and despite a suspected incomplete "bedding in" of the brakes, braking performance was up to a reasonable standard.
First 30-ton artic tested
The Leyland Freightline /Scammell 30-ton artic was the first British outfit for its weight to have been tested by COMMERCIAL MOTOR and this gave a second chance to sample the comforts afforded by the Leyland Ergomatic cab. Fuel consumption on normal-road running was found to be at an acceptable level although the engine got a bit thirsty when running at high speed on
motorway. Against this, acceleration as returned were better than on many cs tested previously at 24 tons gross and general braking performance was very (I. If anything, braking figures could e been better if more work had been done the front-axle units and this would also • e given a much better performance ing the secondary-brake tests.
tic in its element on M6 The Atkinson /Dyson 30-ton gross artic eived a considerable amount of praise for way it performed on the motorway. This ISSiS had a Cummins in-line engine iducing 212 b.h.p. net and appeared to be its element when running at high speeds M6. It confirmed its pleasure by returning excellent figure of 8.9 m.p.g. at an :rage speed of 42.8 m.p.h. Braking formance was also found to be excellent I the times for acceleration would again t have disgraced a vehicle running at the wious maximum gross weight of 24 tons. The heaviest normal haulage vehicle ted in the year, the Mack /Northern 32 ton )ss artic, was loaned for the test by P. and Contract Ltd. who operate some of these aerican six-wheeled tractive units with tdem axle semi-trailers. Fuel consumption ures were low by British standards but a ; advantage claimed by the operator was mplete reliability and the fact that drivers 3 complete 400 miles every night regards of conditions. Braking tests from 20 p.h. only were completed because after it test (a good figure was obtained) the ni-trailer headboard broke. By any stanrd the Mack is an unusual vehicle for itain being a normal-control design and it is interesting that although grossing 32 is the payload was only about half a ton tter than 30 ton g.t.w. tractive units tested. Taking the smallest vehicle in the "Special 'pes" section the Austin Gipsy gave a very od account of itself on the FVRDE test cuits at Bagshot Heath and Chobham. Le model proved itself to be completely at me in conditions as bad as vehicles meet ywhere in the world. There should have en a test of a second vehicle of the same
type but trouble after part of the test was completed has held up publication of a report so there is nothing this year with which to compare the results obtained with the Gipsy. These were, however, about the average for a model in the same class.
Testing the Dennis F36 fire appliance was quoted as being a delightful experience. This machine had a Rolls-Royce 197 b.h.p. petrol engine which gave it an outstanding performance and maximum speed was over 70 m.p.h. Braking figures matched those obtained on performance checks and as these are the most important points about a fire appliance, the fuel consumption obtained of just under 7 m.p.g. was relatively unimportant. The same remarks apply to the Dennis/Metz Turntable Ladder which has only just been tested. This had a higher gross weight than the F36 and as a result fuel consumption was worsened but the general performance was to the same high standard.
Two dump trucks
The two dump trucks appearing in this section were tested in conditions under which they are designed to operate as well as being given normal road tests. Because the location of the test areas was quite different it is difficult to compare fuel consumption returns and whilst the run on the AEC Dumptruk was completed at a gross weight of just over 24 tons, the Scammell Himalayan, grossed over 29 tons. Both fuel consumption test circuits were over very hilly country. Brake tests on the AEC were carried out in very wet weather and stopping distances could not be obtained. Tapleymeter readings of 48 per cent can be compared with 54 per cent obtained with the Himalayan. Both machines performed very well on quarry work. Power steering was fitted to both dump trucks but while the systems were generally satisfactory, that on the Himalayan tended to take control of the vehicle when it was on normal roads and required frequent correction. Criticism was made of the gear change mechanism on both chassis.
Three passenger vehicles
The three passenger vehicles tested during the year are not really comparable one with the other. the Bedford VAM having a 45seater luxury body whilst the Albion Viking and AEC Swift had service bus bodywork with 40 and 53 seats respectively. The Bedford was reported to be a very pleasant vehicle to drive and praiseworthy for the almost roll-free ride given. Braking tests produced good figures as did acceleration runs. Fuel consumption was around the average for similar p.s.v.
The Albion and AEC buses had something in common—rear-mounted engines. But while that of the AEC Swift produced 142 b.h.p. and was located horizontally, the 125 b.h.p. unit in the Albion Viking was mounted vertically. Semi-automatic Monocontrol transmission helped to give the Swift an excellent acceleration performance and the suspension could not be faulted. Fuel consumption tests also gave good results and retardation figures on the brake tests were well above average. In the case of the Albion Viking, fuel-consumption tests gave very good returns indeed and in spite of an impression of sluggishness, acceleration times were more than adequate for the class of vehicle; so were stopping distances recorded on the road tests. A criticism of the test vehicle was that there was excessive delay in time taken for the engine to die down when making upward gear changes and although this proved no difficulty when fully used to driving the machine it was felt to be a point needing attention.