[DMR7717]

So I read all the threads about the knocking on cold-starts associated with the 5.7L and yes, mine does it too. I only have 450 miles on it and I didn't hear it when I test drove it.

What I also have been experiencing is slight engine pinging or at least what sounds like engine pinging. I'm not sure if I'm hearing valve noise or timing chain clatter but in any case, it's annoying and worrisome.

I purchased this truck over the GMC Sierra becuase I wanted some reliability. I was so concerned that my dealer "through in" 100k powertrain warranty to match my GMC offer. That's what sealed the deal for me. I have owned two Toyota Tacomas previously and one went 200k miles before I sold it and the other has 146k miles on it without ever seeing the dealer.

I traded in a '05 F-250 Lariat when I purchased this truck. It only had 40k miles on it been had been back to dealer several times with a variety of problems, 4WD did not engage, alternator failed, washer fluid pump failed, worn ball joints....etc.

Is anyone experiencing similar conditions?

 

[07 firecrew]

and I reinterate, go to a higher octane fuel. different cilmates, have varying affects on performance, you may have to counter, with higher grade fuel. i run midgrade and sometimes premium, my truck is stout.

 

[bbfirebird]

and I reinterate, go to a higher octane fuel. different cilmates, have varying affects on performance, you may have to counter, with higher grade fuel. i run midgrade and sometimes premium, my truck is stout.

That wouldn't be the case if it's only on cold starts and disappears as the engine warms up. Detonation usually occurs while accelerating, not when the engine is idling.

 

[Rustywrenches]

That wouldn't be the case if it's only on cold starts and disappears as the engine warms up. Detonation usually occurs while accelerating, not when the engine is idling.

I would like to add, a warm or hot engine is more likely to ping than a stone cold engine. I understand the cold knock is audible only when the engine is cold and gets quiet after the engine is at operating temp. I would think the cold knock situation is not pinging / detonation.

 

[mxsjw]

Read the part "Effects of octane rating", all of it.

Octane rating - Wikipedia, the free encyclopedia

 

[confederate2]

So I read all the threads about the knocking on cold-starts associated with the 5.7L and yes, mine does it too. I only have 450 miles on it and I didn't hear it when I test drove it.

What I also have been experiencing is slight engine pinging or at least what sounds like engine pinging. I'm not sure if I'm hearing valve noise or timing chain clatter but in any case, it's annoying and worrisome.

I purchased this truck over the GMC Sierra becuase I wanted some reliability. I was so concerned that my dealer "through in" 100k powertrain warranty to match my GMC offer. That's what sealed the deal for me. I have owned two Toyota Tacomas previously and one went 200k miles before I sold it and the other has 146k miles on it without ever seeing the dealer.

I traded in a '05 F-250 Lariat when I purchased this truck. It only had 40k miles on it been had been back to dealer several times with a variety of problems, 4WD did not engage, alternator failed, washer fluid pump failed, worn ball joints....etc.

Is anyone experiencing similar conditions?

If you are talking about pinging under load such the "marbles rattling in a can sound", we have had a lot of extensive threads about this over the years, many of which I started. But they were all about the 4.7 not the 5.7 so I don't know if they would be much help to you. I will condense about 20 threads and probably a thousand posts into a couple of sentences here as it relates to the 4.7. It is normal, at least that is what the dealer says. I will say that I had good results switching to 89 octane and accepted the problem for the life of the truck but my problem was ultimately cured after the truck was nearly 4 years old. It was when i retired last year and moved from sea level or there abouts to 600 to 1800 feet above sea level. That instantly solved the problem. Don't ask me how as I don't know anything about the mechanics of it but maybe someone more knowledgeable can explain. It may just been different additives and not the altitude, don't know.

Again I know you don't have the 4.7 but maybe this info can give you a place to start.

Good luck.

 

[DL]

So is everyone swapping to 89 octane? No more knocking?

 

[Rustywrenches]

Read the part "Effects of octane rating", all of it.

Octane rating - Wikipedia, the free encyclopedia

Very interestiing reading! That does explain a few things..........:tu:

 

[Cooper S]

I don't have a "pinging" sound so I am not going to switch. I am going to continue to use 87 octane from a top tier company with a can of BG 44k every 6k miles or so.

 

[paulphilly]

So is everyone swapping to 89 octane? No more knocking?

I have been using 89 Octane since I purchased my truck 4 weeks ago and after 1500 miles, have not had any symptoms of "knocking". There is several other members running higher Octanes and are not having any knocking as well. So, there does appear to be a correlation between the 89 rating and no knocking.

 

[Rustywrenches]

I have been using 89 Octane since I purchased my truck 4 weeks ago and after 1500 miles, have not had any symptoms of "knocking". There is several other members running higher Octanes and are not having any knocking as well. So, there does appear to be a correlation between the 89 rating and no knocking.

That certainly is worth a try and a very cheap experiment. Nothing to lose but a few $$ :tu: