99 GMC Suburban just turned 100,000. When it is cold it makes a fairly
distinct tapping noise when first started. The sound increases/decreases in
concert with engine speed, and stops after about 30 seconds. It only happens
the first time the truck is started each day.
I took it to the dealer and they started with "maybe it is time for a new
truck." They said they put something in to clean carbon deposits, but
suggested I hold off on needed service (some gasket replacements and a brake
job) until they could see if the truck is "worth fixing."
The exterior and interior are in great shape. I've had it since it had 9
miles, changed the oil every 3,000 miles and it's lived in a garage all its
life. It rides fine, and gets up to highway speed with little effort. I was
getting a little pinging last summer and changed to higer octane gas (85
octane I think).
What is up with this? Why would the dealer suggest that it is not worth
fixing (or may need a new engine)? They muttered something about a broken