User guide

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STAMPEDE 4X4
ADJUSTING YOUR MODEL
Adjusting the Slipper Clutch
The model is equipped with an adjustable slipper clutch, which is
built into the large spur gear. The purpose of the slipper clutch is
to regulate the amount of power sent to the wheels to prevent tire
spin. When it slips, the slipper clutch makes a high-pitch, whining
noise. To adjust the slipper, remove the slipper gear assembly from
your model (see page 25 for instructions), and turn the adjusting nut
clockwise to tighten or counterclockwise to loosen. Adjust the slipper
so that you can hear it slip for a moment from a standing, full throttle
start. (Learn more about adjusting the slipper clutch in the sidebar.)
Wheels and Tires
Many types of aftermarket tires and wheels can be adapted for
use on your model. Most will affect the overall width and the
suspension geometry of the model. The offsets and dimensions
designed into the model’s wheels are intentional; therefore, Traxxas
cannot recommend the use of other non-Traxxas wheels with
different specifications. The diameter of the wheels is an innovative
design, and there is a variety of different tires available for you to
experiment with in addition to the included tires on the model
(listed in your parts list). Experimentation with different types of
tires is recommended to see which ones work the best on the
terrain where the model is run. When selecting tires, consider the
overall diameter and the rubber compound (hard or soft). If the
overall diameter of the tire is significantly increased, you will need
to use a smaller pinion gear to compensate for the larger tire. Soft
compound tires with many short spikes generally work better
on hard, dry surfaces. In loose dirt, a tire with large spikes should
perform better. See your parts list for accessory wheels and tires.
TUNING THE SEALED GEAR DIFFERENTIALS
The action of the model’s front and rear gear differentials can
be tuned for different driving conditions and performance
requirements without major disassembly or removal of the
suspension system.
From the factory, the differentials are sealed to maintain consistent
long-term performance. Changing the oil in the differential with
either lower or higher viscosity oil will vary the performance
characteristics of the differentials. Changing to higher viscosity oil
in the differential will reduce the tendency for motor power to be
transferred to the wheel with the least traction. You may notice this
when making sharp turns on slick surfaces. The unloaded wheels
on the inside of the turn have the least traction and tend to spin
up to extremely high RPMs. Higher viscosity (thicker) oil causes the
differential to act like a limited-slip differential, distributing more
equal power to the left and right wheels.
Stampede 4X4 will generally benefit from higher viscosity oil when
climbing or racing on low traction surfaces. Note: Heavier oil will
allow power to be transferred even with one or more tires off the
ground. This can make the vehicle more likely to overturn on high-
traction surfaces.
From the factory, the front and rear differentials are filled with SAE
30,000W viscosity silicone oil.
Only use silicone oil in the differentials. Traxxas offers various
viscosity oil between SAE 10,000W, and 500,000W (see your parts
list). The differentials have to be removed from the vehicle and
disassembled to change/replace oil. Follow the steps below to
access and refill the front and rear differentials:
Front differential:
1. Remove the two 3x15mm button-head screws that secure the
top bumper mount to the differential case.
2. Turn the chassis over and remove the three 4x10mm
countersunk screws that hold the bumper/skid plate to the
bulkhead. The two rear screws do not need to be removed.
3. Slide the bumper assembly off the chassis.
4. Remove the 3x15mm button-head screw from the differential
tie bar.
5. Slide the tie bar off the truck.
To achieve a good starting
point for the slipper clutch
in this model, remove the
slipper gear assembly from
your model (see page 24 for
instructions) and tighten
the slipper clutch adjusting
nut clockwise until the
slipper clutch adjusting
spring fully collapses (do
not over tighten), and then
turn the slipper clutch nut
counterclockwise one full
turn.
Do not run your model with
the slipper clutch adjusting
spring fully compressed. The
minimum recommended
slipper clutch setting is 1/2
turn counterclockwise from
fully compressed.