Spark Knocking

[lawnspecialties]

2013 F350 with the 6.2L. Around 44,000 miles.

Pulling the Work & Play, I guess we're around 15,000 lbs. total. I've been noticing lately some detonation; especially on hills. I've read before that some detonation is OK and expected when towing big loads. But I tow with this truck a lot.

Should I be concerned? Should I go ahead and bump up to 89 octane?

[carringb]

A small exhaust leak at the manifold can sound like knock too. At the very least, it would be a good idea to take it to the dealer, and let them do diagnostics. They'll be able to see if its actually knocking or not, or if its a non-harmful noise.

[marcsbigfoot20b]

What altitude are you at? The higher you go the lower octane fuel you can use.

I ALWAYS use the highest octane fuel available when towing. Actually I always use the highest all the time since both Tahoe and Vette are modified and tuned.

At $0.25 a gallon more for premium times 30 gallons if you have a big tank, that is a whopping $7.50 of insurance, more power and better mileage, plus less knock or ping.

Or you can try the Lucas red bottle octane booster......one of the few that actually works for $9.

[ROBERTSUNRUS]

🙂 Hi, Gas pings can destroy pistons. Your engine could be carboned up. Or have a computer problem. Or are you running cheap gas from Albertson's, Von's, Joe's dairy, or any other no-name gas station. (also Arco) Junk gas. "The money you save will cost you later"

[deltabravo]

ScottG wrote:
Knock is NOT ok and will do lots of damage if it continues.
My guess is there's something wrong with the knock, 02 or other sensor or EGR valve.
I would get it fixed before you destroy your valve guides or blow a hole through a piston.

Ditto.
Modern computer controlled engines should not knock.

I'd take it to a dealer for a check-up. Something is amiss.

[BenK]

Your truck should have a knock sensor...it is NOT working for some reason and
should have set a code(s)

Bumping up the octane is only a poor band aid for something that *WILL* destroy
your engine

*IF* that is an ignition knock...it could be something else altogether

I've had folks tell me it is ignition knock that turned out to be a rod going bad

Have it checked out ASAP and get the code....again, in today's ICE's...they
have knock sensors to either retard or go into limp mode.

Knock sensors are cheap and hope that is all it is

DO NOT DRIVE IT FAR while it is this way

[ib516]

89 or 91

[Greene728]

Any time I'm towing I use nothing lower than 89 octane. And most of the time 93. But never anything less than the 89. When pulling heavy, I figure the motor needs any help I can give it. Plus,in my truck I can honestly tell a noticeable difference when pulling with the higher octane fuel. I will run the 87 when running empty and just being a DD. I've only had the truck since January and it has 32,750 miles, but so far not problems and no knocking. Plus she tows like a beast!

[45Ricochet]

Modern gasser should take care of your detonation, but it sounds like yours isn't for some reason :H I would definitely try more octane since your most likely out of warranty.
As said, many engines do require premium. Whether the manufacture admits it is another story :W
DW car has a little sticker on the gas fill hole " PREMIUM GAS ONLY" although it is supposed to adjust timing when detonation occurs. It don't have a hitch so I'm not sure if it actually works.
Let us know how the higher octane works out.

[ScottG]

Knock is NOT ok and will do lots of damage if it continues.
My guess is there's something wrong with the knock, 02 or other sensor or EGR valve.
I would get it fixed before you destroy your valve guides or blow a hole through a piston.

[naturist]

Do be aware that as gas engines get more miles on them, the octane requirements go up. Slowly, to be sure, but it might not be a bad idea to use higher octane fuel. Can't hurt anything except perhaps your wallet, and might prevent more expensive damage down the road.

[jus2shy]

Is there anything in your owner's manual about using higher octane when towing? I know that certain dodges/rams have that, and I believe the ecoboost trucks also have some language about using higher octane when towing. With modern engines, the ECU should know when to take action against detonation.