1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140 
VEHICLE HISTORY
Page 133
If you've noticed an error in this article please click here to report it so we can fix it.
Seddon Atkinson 301 8x4 Multiwheelers At the time of the road test of the Seddon Atkinson 301R30.L25, 8x4 tipper, the Cummins LT10-250 turbocharged engine was considered as the lower-powered alternative to Gardner 6LXDT and Rolls Royce 265Li diesels both rated at 189kW. It was not that much lower in power though, as the output of the LT10 was (and is) 180kW (241hp).
The model became the 3-11 in October 1986 and the following March the charge-cooled version of the Cummins engine the LTA10-290 was made the alternative to the LT10-25.
The May 1986 test of the 301 produced some very good results, particularly in fuel consumption. And it is also worthwhile looking at the results of a later test of the 3-11 with Cummins 216kW (290hp) engine. This was published in CM of 28 April-4 May 1988 and shows what difference an increase of 16% in output makes.
It has become very common for higher power versions of basic designs to give better fuel consumptions than their less-well-endowed partners, probably due to a more leisurely driving technique being possible with the ability to maintain engine speeds at a more ideal point for economy.
This, however, was not the case with the 301 and 3-11 eight wheelers though. The two machines certainly gave excellent figures, but it was the lower powered 301 which gave the better consumption, producing a record 33.711t/1001cm (8.38mpg) over CM's special tipper test route. This compared to the 35.291it/100km (8.01mpg) which nevertheless put the 3-11 into third place
when tested later.
As might be expected, the 301 was somewhat slower than the 3-11 in completing the test by some 51cm/h from an average of 64.6 to 59.9km/h. It is noted in the test report that due to loading difficulties the 301 eight wheeler was running about a tonne below the 30.48 tonnes legal maximum. This was unlikely to affect speeds unduly, however, and computer checks indicated that the "missing" weight would affect fuel consumption to a small extent only, making it 34.31it/100km (8.23mpg) at the worst.
Unladen weights of both models were commendably low, braking was smooth with no locking (although peak efficiencies were only just over 60%), standard Norde rubber suspension at the rear bogie gave an even ride with a little roll and the exhaust brake worked well.
Cab interior noise was not seen as a problem although readings at 60mph of 77dB(A) on the 301 and 79dB(A) on the 3-11 were quite a lot higher than was becoming the norm on that class of vehicle in the mid 1980s. On the other hand, criticism was made of the characteristics of the Fuller gearboxes in both test vehicles the 7609A in the 301 and the 11609A in the 3-11. These were not the same points, the tester of the 301 complaining at the slowness of the change action in the lower ratios which made for difficulties in climbing the steeper hills, whilst the point made in the 3-11 report covered the wide spacing between 7th and 8th and 8th and top ratios, which made it impossible to hold the engine rev counter needle in the green economy sector at all times.
In both tests there was also references to the age of the cab. It was basically the same for both 8 x 4s, but the 3-11's had a number of improvements over the 301, and in fact the 3-11 report made the comment that the cab was a "surprisingly pleasant place in which to work."
As indicated, the Seddon Atkinson 301 models were superseded by the 3-11 in late 1986 with cab improvements and some detail changes. In March 1987 the Cummins LTA10-290 was made available in the 8x4 range in the 3-11 R30.L29 and at the same time the higher-rated Fuller R1'X-11609A nine-speed gearbox was standardised in both chassis, replacing the RTX7609A in the R30.L25.
The Cummins LT10-250 and LTA10-290 are now the only engines offered in the 3-11 eight wheelers and whilst both have the same transmission as standard, the options differ. Behind the LT10-250 in the R30.L25 Seddon Atkinson supplies the Spicer SST 8010-5A 10speed box, whilst the alternative for the higherpowered R30.L29 is the Eaton Thin Splitter TS0 11612 12-speed. All these gearboxes have overdrive top ratios.
Apart from these changes, the 3-11 8 x 4 models have continued with virtually the same specification from the 1986 test vehicle to the present time. There have always been two tipper wheelbases 5.87 and 6.35 plus a 6.35m with extended rear overhang for haulage application and axles, steering, suspensions, brakes, etc. have again stayed unchanged.
At the time of its test, the 301 8x4 had a net list price of £39,710 as against £45,268 for the 3-11 with 290 engine when it was tested some two years later -a difference of 14%. Current price of the 3-11.R30.L25, the direct successor to the 301 tested is £48,710. an increase of £9,000 or 22.7%. This compares to a 15% rise in Retail Price Index