I've been running Quaker State Defy 5W30 in my 95 GMC 1500 with the 5.0 TBI engine. I put about 1000 mi a year on it hauling firewood and kayaks and do a yearly oil change in the fall. This year I noticed I'm having a hard time finding Defy anymore. I remember that being recommended based on the flat tappet design and additive package.
What's a good replacement for the Defy? Note that this engine seems to have leaky valve seals as it will belch and cough a bit with white/gray smoke until it warms up, after which it runs great (only happens on cold starts when it's been sitting a while).
146,000 mi on this beast so far.
Thanks.
What's a good replacement for the Defy? Note that this engine seems to have leaky valve seals as it will belch and cough a bit with white/gray smoke until it warms up, after which it runs great (only happens on cold starts when it's been sitting a while).
146,000 mi on this beast so far.
Thanks.
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