Buhler 535 - Manual (Page 129)

3-00
435/485/535
Tractor Weight Distribution
Although Buhler Versatile 4WD tractors are
manufactured with an approximate weight distribution
of 65% - 67% over the front axle and 33% - 35%
over the rear axle, the intent of the design is to have
the tractor operating in the field with an ideal 50/50
dynamic weight distribution .
The benefits of operating a tractor in the field under
the ideal 50/50 dynamic weight distribution are:
 . The work is divided equally between the axles,
allowing a more even distribution of work and
load .
2 . Compaction is lessened since the axles are the
lightest force possible on the soil . If a 3,636
kg (30,000 lbs) tractor has a 50/50 split, each axle
exerts a force of 6,88 kg (5,000 lbs) . A 60/40
split would create an 8,82 kg (8,000 lbs) force
under the heavier axle, increasing the compaction
by 364 kg (3000 lbs) .
3 . Maximum traction, with the least rolling resistance,
is gained by distributing the load equally between
both axles .
4 . With the total tractor weight equally divided (under
load) on all four wheels, you increase reliability by
spreading the torque output of the tractor equally
to all four wheels . The greatest torque always goes
to the wheels with the most weight .
NOTE: The tractor has a maximum axle weight
capacity:
Model
Maximum continuous weight per axle
435 27,000 lbs .
485 30 .000 lbs .
535 32,000 lbs .
(Based on 00 lbs/hp x 60%)
Calculation of Ballast
The following information is provided as a guide for
proper ballasting:
Shipping Weight and Fore/Aft Ratio
The shipping weight of the tractor will be approximate
distributed at 65% - 67% on the front axle and 33%
- 35% on the rear axle .
Do not assume that every tractor will come from the
factory with this weight distribution.
Various options and wheel packages will significantly
change the weight of the tractor . Determine the
shipping weight BEFORE any ballast is added to the
tractor by weighing the tractor on a scale . This is the
most accurate method of determining actual tractor
weight and ballasting the unit correctly . Possible
locations of a scale of adequate size to weigh the
tractor would be a feed/fertilizer store, asphalt plant,
gravel quarry, grain elevator, etc .
NOTE: There is an additional method of calculating
the shipping weight of the tractor using calculated
weight from theoretical value charts located in the
Section 6 of this manual. Weighing the tractor on a
scale is preferred.
When weighing the tractor, pull the front axle on the
scale first . Make sure the inside wheels of the dual or
triple tires are fully on the scales and the outer tires
are off of the ground . Since most scales are less than
3 m (0") wide, driving the inner wheels up on wooden
blocks will accomplish this . Repeat this procedure for
the rear axle . Record the unballasted weight of each
axle . Add the weight recorded for each axle together to
get a total tractor shipping weight . Divide the individual
axle weights by the total tractor shipping weight to get
the front to rear weight distribution percentage .
Section 3 - Operation
Ballasting