Synthetic & Valve Guides

Joined
May 22, 2006
Messages
750
Location
N. Calif - State of Jefferson
I spoke with another GM truck owner this weekend & he was told by his mechanic NOT to use any synthetic oil in 1990 era GM v-8 engines....because "it will ruin the valve guides". Which he also claimed it did on his 1991 v-8 motor. Does this sound in anyway plausable? As soon as he told me this, I figured that his mechanic just fed him a line in order to do the repair. GL
 
Joined
Oct 20, 2005
Messages
11,857
Location
PA
Maybe the mechanic switched to a synthetic oil right as his valve guides were failing...
 
Joined
Jun 25, 2009
Messages
4,065
Location
Chicago, IL
nope. ya know, I have a friend (now retired) who was a service manager at a dodge dealer for 30 years.... he always thought that synthetic was [censored]. he also would choose one favorite oil and then anything else would "ruin your engine". old school thinking, I guess....
 
Joined
Oct 12, 2008
Messages
233
Location
Pittsburgh,Pa.
No Way!! How can synthetic oils destroy valve guides? Another mechanic that knows absolutely nothing about oils. There are many of them out there!
 
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