occasional valve tapping sound

[kamuela-1]

Heh LS owners, I have a 2003 V-8 LS and every once in a while, especially when the engine is a little cold, I hear what seems to be a "valve tapping noise" coming from the engine.

This does not happen all the time and the dealership is telling me that it's the sythetic oil I'm using. I use 30-5, pure synthetic either Castrol or Mobil-1. Anyone experience a similar problem and I doubt it's the oil, but I could be wrong. I only have 11,600 miles on the car.

Thanks for your time

kamuela-1 :confused: null

[eL eS]

hey castrol is not pure synthetic stick with mobil 1. If you change back and forth you could be developing foam in the oil becasue when the dino stuff mixes with synthetic is can foam up.

[purelux]

Many mechanics are "old school" when it comes to synthetic. I know when my brother had a 93 taurus sho they recommended not to use synthetics due to a lower moly content. But then when the mobil 1 with supersyn came out it had a improved formula which addressed the issue. The syn is actually stronger than dyno oil in general espically mobil 1 or amsoil or redline being "true synthetics." If the oil quiets the tapping then its still tapping its just shutting it up. Thats like propping a coaster under an uneven table leg. Doesn't make the legs even it just makes up for a failure or factory build flaw. Have you tried different premium gas maybe its knock? My brother had his atx rebuilt in the sho and i asked about them using synthetic. guy said we don't use it and it doesn't make any difference from what he's seen. So i asked do you use it, he said no, does anyone you know use it, said no, any customers etc... So basically through no experience and neaver working on a car that had it and regardless of synthetic not being a brand but a designation of fluid he told me this. The car went about 65k on the original tranny within the 1 year warrenty we went through 3 trannies and 2 "adjustments." That is besides the times when they "couldn't find anything" The tranny that we had to make them hurry up and fix within the last 3 weeks of warrenty so we could sell the car was the only good one. The only one they didn't touch just bolted it up it was a used non-rebuilt one. And the only one that actually shifted right. For those of you that don't know heat kills a tranny and the sho didn't have room to house an adequatly beefy atx. So why would you want a fluid that could hold up to more heat and prevent wear better. So you can rebuild that tranny in another year after warrenty. Oh and they also said there was no shift kit for that car. Pop the hood of an amg mercedes it'll say factory fill mobil 1. I think it should hold up in a 250hp 3.9 if it can hold up in those 350 hp and way up AMGs.

[thamarkman]

Is 30-5 the oil that is recommended? If not change to Ford's specs. I've heard the LS needs the recommended oil.