My V10 sounds like it's got an intermittent knock, especially at start up.

The truck pulls like normal, otherwise runs great. Other than an actual rod knocking (why would that be intermittent?) what else could this be?

Does the exhaust manifold studs make a sound like this after they break? I don't really know what to do at this point. Dont have the money to pay someone to tear my truck apart just to tell me its exhaust studs.. LOL..

Also, I think that I have the transmission access panel rattle.. Could the knock be related?

Thanks!

Jim

 

When my truck is cold upon first start up,if you try and take it above 2000rpms it will sound like a knock. Until after it warms up,i presume its detonation but dont know for sure. When my studs broke it was just an annoying loud tick,could be a knock i suppose.

 

check for broken exhaust studs..

bet thats it, and i bet u have at least 2 broken.

 

Mine also has a knock when it is cold it sounds like a rod to me could be piston slap I guess but what ever it is I don't like it, but it quits after 30 seconds to a minute after running and it has not gotten worse in the 20,000 miles I have owened it. (158,000 on the clock) I DO KNOW IT IS NOT EXAUST STUDS it's an inturnel knock probably something not getting oil as soon as it wants.?

 

Mine had what I assumed was an exhaust leak that I couldn't find no matter how hard I tried. Turned out to be a combustion leak all right, except it was leaking from the loose spark plug which finally blew out after driving it for several months. Better at least check 'em out.

 

Studs everything is cold and shrunk accordingly you start up and the dreadful clang, knock, noise.
Once the heat gets into the parts they expand and tighten up and things normalize, sound wise. That's the comforting scenario I have come up with for this sound.
On cold mornings for sure knocky clang clang All warm summer start ups are normal. During a cold snap I made sure to plug in. When I started it on a warm engine things were normal. Now I need to define normal. There isn't any time for 11yrs driving this truck that the Exhaust wasn't clinging, clanging, creaking or rattling.
But I still Love it....

 

Mine also makes some slapping/knocking sounds when cold. After a minute or it goes away. I've come to the conclusion it's "normal". I kind of always remember it being there but I'm going to check the plugs anyway.

 

I think the plugs check is a good idea
Oil pressure check
Listening with a stethoscope
Crank end play
Generally making yourself comfortable.
There have been spun bearing threads come across the forums.

 

Mine does the same thing on cold startups. I changed oil and used Motorcraft synthetic and put a quart of Marvel Mystery oil in and it is quieter and does not last as long. I hate rattles,ticks,clanks and thuds.

 

What oil(viscosity, weight, brand) and filter are you using?

 

Oil is Mobile 5000, filter is Motocraft (I believe in OEM filters). Weight is 5w20. I normally use Motocraft synthetic blend but the store was out and I needed to change the oil for my vacation.

 

I'm sorry if i missed it but how many miles you got on it? My 99 knocks a little at start up cold too. Sounds like a little piston slap. I've got 277,000 on mine. But once it's warmed up I don't hear it. I've looked for exhaust leaks and gone over it looking for anything but nothing else stands out.

 

I got 146k on it. No worries, it's still running great, ran it all day on Sunday just messing around. Not really F350 worthy but I got to drive my truck and the wife got some shopping done.