V10 piston slap
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Joined: Jan 2002
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Tony G
The factory pistons all have the skirts hard lube coated...seems to be an industry standard now as there are many other stock motors that have high tech coatings on many of the innards.
i have heard the piston slap on 5.4 V8 bat never have heard it on my limited exposure to only 10 different V10 motors.
My suspicion is typical American manufacturing is the cause. Say a motor that is bored slightly on the large side of the allowable tolerance and one or more pistons on the small side of the allowable dimension so you have the max allowable difference.
Another thought was simply a particular lot of pistons that were not forged properly or machined properly. I read somewhere that these pistons are a slight oval and not perfectly round. So if that is true then maybe the assembler did not get the orientation correct... I don't really know, except to say the one guy I see with the 5.4 and piston slap has over 100,000 miles on the truck so it does seem to be just an annoying concern.
The factory pistons all have the skirts hard lube coated...seems to be an industry standard now as there are many other stock motors that have high tech coatings on many of the innards.
i have heard the piston slap on 5.4 V8 bat never have heard it on my limited exposure to only 10 different V10 motors.
My suspicion is typical American manufacturing is the cause. Say a motor that is bored slightly on the large side of the allowable tolerance and one or more pistons on the small side of the allowable dimension so you have the max allowable difference.
Another thought was simply a particular lot of pistons that were not forged properly or machined properly. I read somewhere that these pistons are a slight oval and not perfectly round. So if that is true then maybe the assembler did not get the orientation correct... I don't really know, except to say the one guy I see with the 5.4 and piston slap has over 100,000 miles on the truck so it does seem to be just an annoying concern.
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