Piston Slap - Is it a Real Thing?

[Moto-Mojo]

I don't see many (if any) threads dedicated to this subject. I see some comments in various threads but I'm curious about this phenomenon known as 'piston slap.' Everyone from the GM Authority on down talks about it being something associated with our V8's. My car certainly seems to have all the classic symptoms.* But is it something that was made up to mask something more nefarious going on like, mis-machined crankshafts, slowly taking out rod bearings? Posters on other forums talk about having vehicles that did it from day one to 200,000 miles.

*lower end and lower frequency knock than that of the clicking of a lifter at startup. But...not a loud knock like a rod bearing. And goes away when up to temp

[1JEWLDSSRS]

It is a real thing. My old 72 Challenger 340 ci did it back when. Not sure what causes it, but when we rebuilt the engine and took the old pistons out, you could see where the piston skirts were hitting the cylinder walls and scraping them. I think it probably was due to the rings being excessively worn out and not sealing them like they should, and therefor causing the pistons to "slap" the cylinder wall on the up and down stroke by not being tight and centered in the bore. Just my guess. The engine when we tore it apart had very badly worn rings. Compression and the oil rings. Burned a lot of oil too.

[Arogg]

My 2010 definitely does it but the HEMI tick in my Magnum is waaaaaaaaaay worse. Almost made me not buy it but super low miles and pretty well set up so i took the chance

[1JEWLDSSRS]

Originally Posted by Arogg

My 2010 definitely does it but the HEMI tick in my Magnum is waaaaaaaaaay worse. Almost made me not buy it but super low miles and pretty well set up so i took the chance

I do believe piston slap and Hemi tick are two different things, since the Hemi's pretty much all have the "lifter tick" issue with their AFM setup, over what the L99 Camaros have, the mopars seem to be worse, especially if they idle a lot and the oil pressure is not keeping the lifters pumped up as they should. My buddies Charger Daytona suffered with that. And I have researched it for him.

[Arogg]

Originally Posted by 1JEWLDSSRS

I do believe piston slap and Hemi tick are two different things, since the Hemi's pretty much all have the "lifter tick" issue with their AFM setup, over what the L99 Camaros have, the mopars seem to be worse, especially if they idle a lot and the oil pressure is not keeping the lifters pumped up as they should. My buddies Charger Daytona suffered with that. And I have researched it for him.

You are correct sir, on both parts. Yes, the hemi tick is a different issue, I was just comparing the "fun" noises my cars make. And yes, the Hemi tick is the oil pressure issue. The Hemi hates idling. So far, no issues with that with mine but i do have the fun dodge canbus electrical issues which are super fun. Also the front end is basically glass and is constantly needing repair but for some reason, i like the weird wagon

[Moto-Mojo]

Most info I have found so far say it's pretty much 'built-in' to the design of the piston/motor. Designed to slap until the thermal expansion seats everything. But others say it could break piston rings at some point. I guess it's kind of like that fuel-leaking SR71. Leaked until the skin heated up at altitude. At least that's what I'm going to tell myself!

Really new one on me that it occurred as far back as 1972. I just heard of it over the weekend.

[1JEWLDSSRS]

Originally Posted by Arogg

You are correct sir, on both parts. Yes, the hemi tick is a different issue, I was just comparing the "fun" noises my cars make. And yes, the Hemi tick is the oil pressure issue. The Hemi hates idling. So far, no issues with that with mine but i do have the fun dodge canbus electrical issues which are super fun. Also the front end is basically glass and is constantly needing repair but for some reason, i like the weird wagon

Ah yes, cool. lol. Yeah when the magnum's came out, I thought they looked kinda cool. Almost bought one. And that sucks that there are ALL those other issues with the car! But if you can fix them, and the car is fun and doesn't leave you stranded, enjoy it!

[1JEWLDSSRS]

Originally Posted by Moto-Mojo

Most info I have found so far say it's pretty much 'built-in' to the design of the piston/motor. Designed to slap until the thermal expansion seats everything. But others say it could break piston rings at some point. I guess it's kind of like that fuel-leaking SR71. Leaked until the skin heated up at altitude. At least that's what I'm going to tell myself!

Really new one on me that it occurred as far back as 1972. I just heard of it over the weekend.

On this note, I will say that I have never seen a broken piston ring caused by that on any of the engines we have been into. Just scuffed up piston skirts where you could see where it was touching. Enjoy your Camaro my brother!!

[Moto-Mojo]

Originally Posted by 1JEWLDSSRS

On this note, I will say that I have never seen a broken piston ring caused by that on any of the engines we have been into. Just scuffed up piston skirts where you could see where it was touching. Enjoy your Camaro my brother!!

Oh, trust me, I do! But I will admit, all the negative stuff you see on the internet/YouTube sure makes me hyper sensitive to little noises coming from it.

[Arogg]

I drive my wife crazy because im constantly pointing out smells and sounds in the cars and she doesn't hear or smell any of them.

[Moto-Mojo]

Well, I'm about half deaf. But I just got new hearing aids. The entire world got full of new sounds. Cranking them to full volume and listening to an LS valve train is not for the faint of heart!

[redcoats1976]

Originally Posted by Moto-Mojo

Well, I'm about half deaf. But I just got new hearing aids. The entire world got full of new sounds. Cranking them to full volume and listening to an LS valve train is not for the faint of heart!

I only wear mine once in a while...is my guitar tone really that high pitched?grandson is a marine and came home on leave to go to the sun and fun fly in as has been our custom for 15 years.this year he made an interesting observation..."all the people with their hands over their ears when the F-16s and Raptors do their show are civilians". I think he was correct.

[Moto-Mojo]

Originally Posted by redcoats1976

I only wear mine once in a while...is my guitar tone really that high pitched?grandson is a marine and came home on leave to go to the sun and fun fly in as has been our custom for 15 years.this year he made an interesting observation..."all the people with their hands over their ears when the F-16s and Raptors do their show are civilians". I think he was correct.

These new ones are ok with my guitar. Much better than the last ones. Still can't beat the half stack with them out though.

I think I'm fixated on the slap thing now. It was really loud to me at start up today. But was gone after it got to temp. Like 1JEWLD said, just drive it and enjoy it.

[1JEWLDSSRS]

Originally Posted by Moto-Mojo

Oh, trust me, I do! But I will admit, all the negative stuff you see on the internet/YouTube sure makes me hyper sensitive to little noises coming from it.

Yeah gotta say, there is a TON of it out there! But most of it is from people who DON'T take very good care of their cars like we do, so you just have to take it all with a grain of salt, and if anything is going to happen, it will, no way around it.