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SLASH 4X4 ULTIMATE
ADVANCED TUNING ADJUSTMENTS
3. Insert the included center differential unit into the rear of the
chassis (where the spur gear/slipper unit was removed). Stand
the chassis up on the front bumper to hold the spur gear steady
and line it up with the pinion gear. The splined shaft adapter
must key into the aluminum center drive shaft.
4. Attach the rear end unit to the chassis keying in the rear output
shaft of the center differential with the opening in the rear
differential. Secure the assembly with the same four button-
head screws.
Tip: Rotate the rear wheels slowly while attaching the rear end
to the chassis to properly set the rear output shaft of the center
differential into the rear differential. You should feel the rear end
set into place. The rear skid plate should lock into the bottom of
the chassis.
TUNING AND MAINTAINING THE SHOCKS
Slash 4X4 Ultimate features high-performance GTR shocks that
utilize friction-reducing titanium nitride shafts and hard-anodized
bodies with PTFE-coated bores to provide the ultimate in precise
damping control. The shocks are filled with 30W silicone fluid. You
may wish to install lower-viscosity (“thinner”) or higher-viscosity
(“thicker”) fluid to alter damping performance to suit your track,
terrain, or driving style. Damping can also be altered by changing
the pistons inside the shocks. The front piston is a 2-hole with
1.5mm diameter holes. The rear piston is a 2-hole with 1.6
diameter holes.
Shock Oil
The 4 oil-filled aluminum 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. From the factory, the shocks are filled
with SAE-30W silicone oil. Only use 100% silicone oil in the shock.
Replacing Shock Oil
For easier service, the shocks should 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 using the shock wrench and suspension
multi-tool (A).
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 with the suspension multi-tool. The
excess oil will bleed out of the small hole
in the shock cap.
7. Tighten the shock cap until snug. Use the
included steel shock wrench to hold onto
the shock body while tightening (A).
Shock disassembly
The shocks must be removed from the
vehicle and disassembled to change the
pistons. Use the shock exploded views
included with the model to aid in the
assembly process.
1. Remove the spring and lower spring
retainer from the shock.
2. Remove the shock cap and empty the
shock body of shock oil (A).
3. Remove the lower cap and the X-ring
from the shock body (B).
4. Use side cutters to grip the shock shaft
just above the rod end. Remove the
rod end from the shock shaft using the
suspension multi-tool (C).
5. Remove the shock shaft with piston from
the shock body out through the top of
the shock body.
Optional shock springs
available from Traxxas.
Refer to your parts list for
a complete part number
listing. Higher rate springs
are stiffer. Springs can be
identified by dots of color on
one end.
Shock Piston Sizes
1.5
1.5
1.5
1.6
1.6
1.6
1.5mm Front
1.6mm Rear
Multi-tool Shock Functions
A. Tighten/Loosen Upper Cap
B. Tighten/Loosen Lower Cap
C. Remove/Install Rod End
