V 2500 P/U 4WD V8-350 5.7L (1987)
Valve Guide Seal: All Technical Service Bulletins
Exhaust - Blue or Bluish White Smoke On Startup
GMC NUMBER:
91-6A-167
GROUP:
6A Engine Mechanical
DATE:
December, 1991
CORPORATE NUMBER: 136007
SUBJECT:
TAILPIPE SMOKE ON STARTUP (INSTALL NEW VALVE STEM SEAL KIT)
MODELS:
1987-91 C/K AND R/V/G/P MODELS WITH 5.0L AND 5.7L ENGINES
THIS BULLETIN CANCELS AND SUPERSEDES GMC TRUCK BULLETIN 89-6A-109, OCTOBER 1989 (CORPORATE BULLETIN # 836546R)
AND GMC TRUCK BULLETIN 90-6A-80, JULY 1990 (CORPORATE BULLETIN # 066102). ALL COPIES OF THE ABOVE BULLETINS
SHOULD BE DISCARDED.
Some owners of the above vehicles may comment on a puff of blue or bluish white tailpipe smoke on startup. This may be caused by oil leaking past
valve stem seals and being deposited on exhaust valve(s).
A new valve stem seal kit (P/N 12511890) has been released to address this concern. The kit incorporates a new umbrella seal with a "viton" insert for
the exhaust valve stem.
Parts are currently available from GMSPO.
Use applicable labor operations and times.
