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TR A X X AS
TUNING ADJUSTMENTS
The Slash VXL 4WD and E-Revo VXL are factory-tuned for optimum
performance in a wide variety of off-road conditions. To tailor the
performance and handling of your model to suit your driving style
and terrain, both models have a number of adjustable features.
Gearing, shock preload and damping, ride height and wheel
camber can all be easily adjusted.
SUSPENSION TUNING
Ride Height Adjustment
The Slash VXL 4WD
and E-Revo VXL both
have threaded shock
bodies that make it easy
to adjust ride height.
Threading the shocks’
preload collars away from
the caps will raise the
vehicle’s ride height (the
distance from the chassis
to the ground), and
reduce the suspension’s
down travel, also known
as ‘sag’ or ‘droop’. This can be helpful in rugged terrain where
extra ground clearance is needed. However, the vehicle’s center of
gravity (CG) will be raised, making it less stable.
Threading the shocks’ preload collars toward the caps will lower
the vehicle’s ride height and increase the suspension’s droop. This
will lower the vehicle’s CG and improve handling, but it will also
reduce ground clearance.
From the factory, Slash VXL 4WD and E-Revo VXL are set up as
shown in the illustration above. At rest, the suspension sags to
about 1/3 of its total travel. This allows the suspension to extend so
the wheel can drop into depressions over rough terrain. This leaves
2/3 of the total suspension travel for compression when absorbing
bumps and landing jumps. These settings are ideal for most
surfaces, and only small changes in ride height should be required
to fine-tune the vehicle’s handling for your particular surface.
Shock Oil
The 4 oil-filled shocks (dampers) effectively control the suspension
movement by preventing the wheels and tires from continuing
to “bounce” after rebounding from a bump. Changing the oil in
the shocks can vary the suspension damping effect. Changing
the oil to a higher viscosity oil will increase damping. Lowering
the viscosity of the oil will cause the suspension damping to be
reduced. Damping should be increased (with higher viscosity oil)
if the model is bottoming easily over jumps. Damping should
be decreased (with thinner viscosity oil) if the model is hopping
over small bumps and feels unstable. The viscosity of shock oil is
affected by extremes in operating temperature; an oil of certain
viscosity will become less viscous at higher temperatures and
more viscous at lower temperatures. Operating in regions with
cold temperatures may require lower viscosity oil. The Slash VXL
4WD’s shocks are filled with SAE 30W oil. The E-Revo VXL’s shocks
are filled with SAE 40W oil. Only use 100% silicone oil in the shock.
Replacing Shock Oil
The shocks have to be removed from the vehicle and disassembled
to change the oil.
1.
Remove the lower
spring retainer and
shock spring.
2.
Remove the upper
shock cap. If you cannot
unscrew the cap with
your fingers, pass the
2mm ‘L’ wrench through the cap’s eyelet so you can apply more
leverage. Turn the cap counterclockwise to loosen it.
3.
Empty the used shock oil from the shock body.
4.
Fill the shock with new silicone shock oil up to the top of the
shock body.
5.
Slowly move the piston up and down (always keeping it
submerged in oil) to release the air bubbles. Let the shock sit for
a few minutes to allow any remaining air bubbles to surface.
6.
Slowly thread the upper cap with the installed shock bladder
onto the shock body. The excess oil will bleed out of the small
hole in the shock cap.
7.
Tighten the shock cap until snug.
Compression 2/3
Sag (Droop) 1/3
Ride Height
To
ta
l T
ra
ve
l
Axle Centerline at Ride Height
Axle Centerline at Max Compression
Axle Centerline at Max Sag
Important:
The shocks are
assembled at the factory with
a center-to-center distance
(between the rod end balls)
of 47.75mm. Any time the
shocks are removed and
disassembled, this distance
should be checked to ensure
proper operation of the
suspension.
47.75mm
