Not sure I trust 5w20 anymore

[GT Pony]

Not really, the only UK ones on here are knackered cars with bearing issues.
I think it is really significant that Aussie and UK cars don't have it. For example Mazman in Sweden had his car delivered at the same time as mine. He got his tick straight away, but the other UK buyers that collected cars around the same time had no ticks, and still don't.

If you read all the posts about that UK ticking S550 GT, you'll see that a renowned engine mechanic came to the shop and did a detailed engine inspection. He claimed all the bearings were fine, and even the rod side clearance was good - even though the shop mechanic measured all the rod side clearances to be out of factory spec.

And the mechanic could get that engine to tick by disabling the ignition coil on a cylinder, which changed the load on the engine, similar to the tick showing up on some cars when the AC is turned on .

Herman the German might have hit the nail on the head with his discovery of a TSB relating to Ford aluminium engine blocks and the tick. He found that it was non linear harmonics that set up vibrations in the block and caused the noise. Any alteration of the natural frequencies of the engine can change them, such as a different oil or some strange gunk added to the oil.

All Coyotes are aluminum, so what's the theory why RHD S550s don't tick? Maybe RHD Coyotes were built with more attention to details and QA.

And why would Ford replace short blocks if it was just some harmonic noise and not caused by some mechanical parts clearance issue. Fird doesn't throw away money on warranty repairs not knowing what the cause really is.

Sponsored

 

[jordi]

Shell owns Pennzoil

Phillips 66 owns Red Line Oil

Is there a possible pattern to the additive package used ?

I bought a 2015 GT Premium at 54K Miles. Changed the oil at 58K. Went with AMSOIL Sig. 5W-20. Car instantly started to tick between 1-2K rpm. Just switched it back to motorcraft filter and motorcraft 5w-20 synthetic blend. Tick is quieter now, but still there around 1-2K. Thinking about throwing in some Cera Tec...

 

[Ace21]

I don't think the tight clearances with lack of oil flow is what's causing the tick. The more I read about this, and the more I experience what's happening with my own car, I really think the tick is the very early stages of piston slap. If anything, guys using heavier oil, 5w30 or even 5w40 and Ceratec additives is lubricating the cylinder liners better to help provide better cushioning and thus quieting of piston slap noise.

I say this because my tick slowly changed from a very small intermittent BBQ tick at idle, into no longer ticking at idle, but now a more noticeable tick once you rev up and exceed 1,000rpm. The tick begins around 1,000rpm intermittently, then becomes a constant tick above 1,500rpm, even when the engine is fully warm.

After driving the car very hard for several minutes at higher RPM (~3,500rpm) to heat up the engine under load, the metals swell and seal the pistons, and the tick is almost completely gone.

After shutting down the engine and letting it cool, the tick comes back after restarting.

This is a perfect example of piston slap, and it all started with a very light intermittent BBQ ticking sound at idle when new.


I also think the possibility of the engine now having a plastic oil pan is why the noise is mostly heard from underneath. The sound of piston slap is insulated by the heads on top, so the cylinder is acting like a sound tube and fires the noise downward, right into the oil pan. Since the oil pan being made of polymers are more flexible than metal, the oil pan itself may also be acting like a speaker of sorts, making the noise inside the engine much more noticeable.

Two things about why this theory isn't sound.

1.) These use hypereutectic pistons that match bore expansion properly so that piston slap is nearly impossible without showing major signs of defect such as mass oil consumption and loss of performance. In other words, piston slap with this type of setup would need some very prevalent, and measurable, issues outside of just noise generation.

2.) Piston slap in cases like with forged pistons, i.e. GT350, are loudest at low load (like AC on) idles than at higher RPM. Also in these cases if you drive before allowing the pistons to expand to operating temp then oil consumption rates will increase. In no case that I am aware of, and I am unaware of a lot, has piston slap been quieter at low load idle and louder at higher RPM.

I personally think that the oil is the start of the issue that can be corrected up to certain point, I am at 3000 miles on my '18 and will be swapping to Rotella T6 5w40.

Sponsored