2008 YAMAHA GRIZZLY 350 torque

8-2
8The service information included in this manual
and the tools provided in the owner’s tool kit are in-
tended to assist you in the performance of preven-
tive maintenance and minor repairs. However,
additional tools such as a torque wrench may be
necessary to perform certain maintenance work
correctly.
NOTE:If you do not have the tools or experience required
for a particular job, have a Yamaha dealer performit for you.
WARNING
EWB01850Never modify this ATV through improper in-
stallation or use of accessories, as it may
cause changes in handling, which in some sit-
uations could lead to an accident. All parts and
accessories added to this ATV should be gen-
uine Yamaha or equivalent components de-
signed for use on this ATV and should be
installed and used according to instructions. If
you have questions, consult an authorizedYamaha ATV dealer.

8-11
8 To install the spark plug
1. Measure the spark plug gap with a wire thick-
ness gauge and, if necessary, adjust the gap
to specification.
2. Clean the surface of the spark plug gasket
and its mating surface, and then wipe off any
grime from the spark plug threads.3. Install the spark plug with the spark plug
wrench, and then tighten it to the specified
torque.
NOTE:If a torque wrench is not available when installing
a spark plug, a good estimate of the correct torque
is 1/4–1/2 turn past finger tight. However, the spark
plug should be tightened to the specified torque assoon as possible.
4. Install the spark plug cap.EBU23314Engine oil and oil filter cartridge The engine oil level should be checked before
each ride. In addition, the oil must be changed and
the oil filter cartridge replaced at the intervals spec-
ified in the periodic maintenance and lubrication
chart.
To check the engine oil level
1. Place the ATV on a level surface. Specified spark plug:
NGK/DR8EA
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
1. Spark plug gap
Tightening torque:
Spark plug:
17.5 Nm (1.75 m·kgf, 12.7 ft·lbf)

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8
NOTE:An oil filter wrench is available at a nearby Yamahadealer.
6. Apply a thin coat of engine oil to the O-ring of
the new oil filter cartridge.NOTE:Make sure that the O-ring is properly seated.
7. Install the new oil filter cartridge with an oil fil-
ter wrench, and then tighten it to the specified
torque with a torque wrench.8. Install the engine oil drain bolt, and then tight-
en it to the specified torque.
9. Refill with the specified amount of the recom-
mended engine oil, and then install and tight-
en the engine oil filler cap.1. O-ring
1. Torque wrenchTightening torque:
Oil filter cartridge:
17 Nm (1.7 m·kgf, 12 ft·lbf)
Tightening torque:
Engine oil drain bolt:
23 Nm (2.3 m·kgf, 17 ft·lbf)

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8
NOTE:The oil level should be at the brim of the filler hole.
3. If the oil is below the brim of the filler hole, add
sufficient oil of the recommended type to raise
it to the correct level.
4. Install the oil filler bolt, and then tighten it to the
specified torque.To change the final gear oil
1. Place the ATV on a level surface.
2. Remove the final gear case guard by remov-
ing the bolts.
3. Place an oil pan under the final gear case to
collect the used oil.
4. Remove the final gear oil filler bolt and the fi-
nal gear oil drain bolt to drain the oil from the
final gear case.1. Final gear oil
2. Final gear oil filler bolt
3. Correct oil levelTightening torque:
Final gear oil filler bolt:
23 Nm (2.3 m·kgf, 17 ft·lbf)
1. Final gear case guard
2. Bolt

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8 5. Install the drain bolt, and then tighten it to the
specified torque.
6. Refill with the recommended final gear oil to
the brim of the filler hole as shown.
CAUTION:ECB00420Be sure no foreign material enters the finalgear case.
7. Install the oil filler bolt, and then tighten it to the
specified torque.
1. Final gear oil drain boltTightening torque:
Final gear oil drain bolt:
23 Nm (2.3 m·kgf, 17 ft·lbf)
1. Final gear oil
2. Final gear oil filler bolt
3. Correct oil levelRecommended final gear oil:
See page 10-1.

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88. Check the final gear case for oil leakage. If oil
is leaking, check for the cause.
9. Install the final gear case guard by installing
the bolts and tightening them to the specified
torque.
EBU23433Changing the differential gear oil (4WD
model)The differential gear case must be checked for oil
leakage before each ride. If any leakage is found,
have a Yamaha dealer check and repair the ATV.
In addition, the differential gear oil must be
changed as follows at the intervals specified in the
periodic maintenance and lubrication chart.
1. Place the ATV on a level surface.
2. Place an oil pan under the differential gear
case to collect the used oil.3. Remove the differential gear oil filler bolt and
the differential gear oil drain bolt to drain the
oil from the differential gear case. Tightening torque:
Final gear oil filler bolt:
23 Nm (2.3 m·kgf, 17 ft·lbf)
Tightening torque:
Final gear case guard bolt:
16 Nm (1.6 m·kgf, 11 ft·lbf)
1. Differential gear oil filler bolt

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8 4. Install the drain bolt, and then tighten it to the
specified torque.
5. Refill with the specified amount of the recom-
mended differential gear oil.
NOTE:
Do not exceed the specified differential gear oil
quantity when filling. Overfilling will cause the oil
to seep out of the breather hose during and after
riding.

The differential gear case capacity is greater
than the recommended oil quantity, therefore
the oil level cannot be accurately checked fromthe oil filler hole.CAUTION:ECB00410Be sure no foreign material enters the differen-tial gear case.
6. Install the oil filler bolt, and then tighten it to the
specified torque.
7. Check the differential gear case for oil leak-
age. If oil is leaking, check for the cause.
1. Differential gear oil drain boltTightening torque:
Differential gear oil drain bolt:
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Recommended differential gear oil:
See page 10-1.
Oil quantity:
YFM350FWA 0.35 L (0.37 US qt) (0.31
Imp.qt)
Tightening torque:
Differential gear oil filler bolt:
23 Nm (2.3 m·kgf, 17 ft·lbf)

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8
EBU25701Installing a wheel 1. Place the ATV on a level surface.
2. Install the wheel and the nuts.NOTE:
The arrow mark on the tire must point toward
the rotating direction of the wheel.
Tapered nuts are used for both the front and rear
wheels. Install the nuts with their tapered side to-wards the wheel.
3. Lower the ATV to the ground.
4. Tighten the wheel nuts to the specified
torques.1. Arrow mark
1. Tapered nutTightening torques:
Front wheel nut:
55 Nm (5.5 m·kgf, 40 ft·lbf)
Rear wheel nut:
55 Nm (5.5 m·kgf, 40 ft·lbf)