GMC GMT 610, Manual

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G/H Van (GMT 610) 2005
G/H V
AN
(
GMT 610
)
14
P
AGE
(Section 8 — continued from previous page)
Gaseous Fuel Conversions
All truck gasoline engines may be converted to use liquified petroleum gas (LPG) or natural gas (NG). Some conversions may cause harmful
effects to the engine. Such fuel systems may require assurances from alternate fuel system manufacturers and/or installers that the
equipment will not cause damage to the engine or the exhaust system.
In the use of dual fuel systems, the intermediate or final stage manufacturer should strictly adhere to the manufacturer’s procedures for
switching from gasoline to gaseous fuel operation. Improper switching procedures may result in overheating and damage to the exhaust
system and the vehicle. The gaseous fuel tank should not be mounted in an enclosed area of the vehicle, such as the passenger compart-
ment, etc., and the system should be vented to the outside of the vehicle. In addition, vehicles converted to gaseous fuels should not be
stored in enclosed places such as garages. Further, General Motors cautions purchasers that the design, location and installation of any
type of fuel storage system involves significant technical and engineering considerations and that these statements on gaseous fuel
conversions should not be interpreted to be an approval by General Motors of any modification to the original equipment fuel system.
Conversions to gaseous fuel should be made in conformance with applicable Federal and State regulations. Removal of emission-control
components and/or the addition of gaseous fuel systems, which could damage or reduce the longevity of those components, could cause
the mechanical and emission performance warranty to be voided.
Exhaust System
Particular care should be taken to prevent the possibility of exhaust fumes and carbon monoxide exposure to vehicle occupants in units
completed by body builders. Holes and openings through the floor and all other parts of the body must be permanently and adequately
sealed by the body builder to avoid exhaust intrusion into any occupant area. If it is necessary to change the exhaust outlet location, the
exhaust discharge must be unobstructed and directed away from occupant areas. Alteration of the exhaust outlet or its position may
increase exhaust noise and render the vehicle illegal in those areas with pass-by noise regulations. All vehicles >10,000 lbs. GVWR come
under Federal noise regulations, vehicles
≤
10,000 lbs. GVWR are regulated by various state and local regulations of the Environmental
Protection Agency; see those regulations for rules, test procedure and noise levels permitted.
Check for proper clearance between body members and chassis components which may in any way affect the reliability and
performance of the vehicle by developing abrasion and wear points from moving parts or degradation from extreme environment or thermal
exposure or may increase interior noise. Any attachments must consider chassis components for jounce and rebound motion at maximum
GVW.
Tail pipe outlet location must be tested statically and with the vehicle in motion to ensure that exhaust gases do not enter through side or rear
windows or underbody seams and holes. Auxiliary power plants should also be tested under the same conditions. Tail pipe exit ahead of rear
wheels is not recommended.
(Section 8 — continued on next page)