Minor Ping/Piston Slap on Acceleration when Warm?

rpr said:

I see numerous posts on noise issues when accelerating and the engine is warm, but they usually end up veering into a different direction where there’s a vibratory rattle from a heat shield or something that’s at fault. My issue seems to definitely be ping and/or very minor piston slap, it does not sound like a vibratory rattle from two components contacting each other.

What’s confounding though is that it’s always been present from day 1 and it does not throw any error codes. Oil looks good. Sounds like a subtle but classic timing related ping.

With no ability to modify the timing on these trucks, has anyone found faulty knock sensors or something like that on their trucks?

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rpr said:

Ramffml: Good info, I wasn’t aware the manual said some pinging was normal. Not normal in my world.

For what it’s worth I have a catch can do I don’t think that will help you.

Also, I have a custom grill that increases airflow to the radiator. Even though in theory once it gets up to operating temp a different grill shouldn’t make a difference, if the temp gauge can be trusted it doesn’t get up to the same temp that it used to with the OEM grill. So I’m not sure if a lower temp thermostat will help either. Let us know either way if you can.

Thanks.

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rpr said:

Backcountry, how many miles on those plugs?

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BackCountryAK said:

My truck also has a ping when warm outside. Pretty much started after the second year of ownership. Truck has had a catch can since new and I changed to a 180 degree thermostat along with a tune to adjust the efan to come on sooner after I noticed the pinging under light load. No change at all even when running our 90 premium in AK lol. The only time it has not pinged in the summer is when I ran 5 gallons of VP C10!

I thought I'd try something different this year before I changed out the winter oil as I've wondered if the pinging could be caused by carbon deposits attributed by wintertime idling and short trips to my job. I ran three consecutive applications of Red Line SI-1 and was hoping for a miracle but the ping is still there and the piston tops are still dirty. I replaced the spark plugs this go around, along with a new PCV valve and made sure the intake manifold bolts were still snug. It's only 46 degrees today so not warm enough to see if anything made a difference (I don't have high hopes). Thanks to Wild One for the gear wrench advise for the plugs (it still sucks but way better than previous times)!

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ramffml said:

What oil are you running, brand and viscosity?

Have you tried switching to an oil that mitigates LSPI (these oils usually use more amounts of magnesium and less of calcium)? I did try this over the winter and I'm almost certain I had less pinging over the winter, but temperatures have also climbed here recently and I know it definitely pings more when it reaches operating temp so it might just be the cold temps that helped vs the LSPI oil.

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ramffml said:

What oil are you running, brand and viscosity?

Have you tried switching to an oil that mitigates LSPI (these oils usually use more amounts of magnesium and less of calcium)? I did try this over the winter and I'm almost certain I had less pinging over the winter, but temperatures have also climbed here recently and I know it definitely pings more when it reaches operating temp so it might just be the cold temps that helped vs the LSPI oil.

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