UPFITTER Bulletin - Fuel System Changes (UI 67)

Publication date: 2003-08-01
Reference number: UI 67

UPFITTER BULLETIN - FUEL SYSTEM CHANGES

UPFITTER INTEGRATION BULLETIN

Reference Number(s): UI BULLETIN # 67, Date of Issue: August 1, 2003

GENERAL MOTORS:

2004 GMT610, Cutaway (03) and Full Bodied Vans (05/06) with all V8 Engines (4.8L, 5.3L, & 6.0L); GMT800, Silverado and Sierra Pick-ups, including ZW9 (Pick-up Box Removal) with all gasoline V8 Engines (4.8L, 5.3L, 6.0L, & 8.1L) (Diesel applications are not affected)

SUBJECT

Fuel System Changes

ADVISORY

This Bulletin is being issued to advise the Upfitter community of recent changes to the fuel system on the 2004 GMT610 and GMT 800.

These changes are as follows:

"Returnless Fuel System," elimination of fuel return line on all gas models except 4.3 L
Relocation of Fuel Filter to interior of tank as part of the Fuel Sending Module
Reduction in fuel filler neck diameter, from 2" to 1"
Addition of FLVV (Fill Limit Vent Valve) at the base of the fuel filler neck, preventing use of aftermarket draw tube (GMT 610 Full Body Vans)

These changes have impacted the upfitters' ability to provide an auxiliary fuel tap for generators and auxiliary engines.

GMT 610, presently, K50 and 7T6 auxiliary fuel tap options are not available. Aftermarket solutions for K50 are currently under development. There will be no aftermarket solutions available for 7T6. Only the factory option of 7T6 will be an approved means of providing an auxiliary fuel tap.

GMT 800's with Pickup Box Removal (ZW9), currently, there is no means of providing an auxiliary fuel tap.

GMT 610 New Fuel Filler Neck Hose Dimensions:

30.0 mm diameter at the fuel filler neck (33 gallon plastic tank)
32.0 mm diameter at the fuel tank spud (33 gallon plastic tank)
30.0 mm diameter at the fuel filler neck (57 gallon metal tank)
25.4 mm diameter at the fuel tank spud (57 gallon metal tank)

GMT 800 New Fuel Filler Neck Hose Dimensions:

25.4 mm diameter at the fuel filler neck
25.4 mm diameter at the metal fuel pipe
34.0 mm diameter at the fuel tank spud

THIS CHANGE EFFECTS ALL 2004 GMT 610's and GMT 800 WITH V8 GASOLINE ENGINE APPLICATIONS (Diesel applications are not affected)

IF YOU HAVE ANY FURTHER QUESTIONS REGARDING THIS BULLETIN, CONTACT UPFITTER INTEGRATION AT 800-875-4742 OR WWW.GMUPFITTER.COM