Knocking Sound On Start Up

[brandonjbb]

When it is cold outside and I start my truck I hear a soft knocking sound. After the truck warms up it goes away. Should I be worried? What is this sound? I drive an 08 Vortec Max. Seen Below

[Stevens03]

Mostly normal, but a quick question about what oil filter your using. Does it have the anti-drain back valve? If it doesn't you'll get that knock. Some have it worse than others but generally isn't a problem. I didn't have it on my 07 Vmax.

[Guest pjblurton]

Mostly normal, but a quick question about what oil filter your using. Does it have the anti-drain back valve?

 

 

I would figure that if the oil filter was vertical, gravity would keep the filter full making an anti-drainback valve unnecessary.

[Ahsmo]

I have the same noise. I think it is something in the valve train not being oiled until oil pressure builds. I'd take it to the stealership but I would have to leave it long enough to replicate the sound...

[J-man67]

Could be the lifters...have it checked out.

[zibzer]

Could be the lifters...have it checked out.

Just throwing this out there but it could be a small leak in the exhaust manifold. Mine did that Nd sounded eerily similar to valvetrain noise

[gleno97]

When it is cold outside and I start my truck I hear a soft knocking sound. After the truck warms up it goes away. Should I be worried? What is this sound? I drive an 08 Vortec Max. Seen Below

 

 

Wombats!! I've seen it before, however, I could be wrong.

 

[dlstewart01]

Mostly normal, but a quick question about what oil filter your using. Does it have the anti-drain back valve?

 

 

I would figure that if the oil filter was vertical, gravity would keep the filter full making an anti-drainback valve unnecessary.

 

 

Its not the oil in the filter you need to worry about. its the oil above the filter in the passages. When you take the filter off see how much oil runs out. If you don't use a filter with an anti drain back valve this oil will drain from these passages and when you start the truck these passages will have to fill up before you have oil pressure and you may get a tick till that happens. Frams have a weak ADBV and sometimes people will get a start up tick using them for this reason.

 

GM specs a filter with an ADBV for a reason. The engineers for the aftermarket filters makers do also...

 

This is an old post from out late and great friend...C&As Dad who sold filters..

 

I am no engineer when it comes to this but I will tell you what I have been told by the engineer at Wix that I know. The AD valve is important on certain engines no matter how the filter is mounted. On our engines and others with the filter mounted upright, it allows oil to remain in some of the passages where it would otherwise drain back.

 

Again, I asked this same question and was told that if it is designed in from the OE, it is vital that it be there.

[Guest pjblurton]

Mostly normal, but a quick question about what oil filter your using. Does it have the anti-drain back valve?

 

 

I would figure that if the oil filter was vertical, gravity would keep the filter full making an anti-drainback valve unnecessary.

 

 

Its not the oil in the filter you need to worry about. its the oil above the filter in the passages. When you take the filter off see how much oil runs out. If you don't use a filter with an anti drain back valve this oil will drain from these passages and when you start the truck these passages will have to fill up before you have oil pressure and you may get a tick till that happens. Frams have a weak ADBV and sometimes people will get a start up tick using them for this reason.

 

GM specs a filter with an ADBV for a reason. The engineers for the aftermarket filters makers do also...

 

This is an old post from out late and great friend...C&As Dad who sold filters..

 

I am no engineer when it comes to this but I will tell you what I have been told by the engineer at Wix that I know. The AD valve is important on certain engines no matter how the filter is mounted. On our engines and others with the filter mounted upright, it allows oil to remain in some of the passages where it would otherwise drain back.

 

Again, I asked this same question and was told that if it is designed in from the OE, it is vital that it be there.

 

 

 

 

 

That is an clear and concise explanation, sir and it makes perfect sense. Thank you.

[07VMax]

my vmax has it and i dont like it lol

[MaverickZ71]

Mostly normal, but a quick question about what oil filter your using. Does it have the anti-drain back valve?

 

 

I would figure that if the oil filter was vertical, gravity would keep the filter full making an anti-drainback valve unnecessary.

 

 

Its not the oil in the filter you need to worry about. its the oil above the filter in the passages. When you take the filter off see how much oil runs out. If you don't use a filter with an anti drain back valve this oil will drain from these passages and when you start the truck these passages will have to fill up before you have oil pressure and you may get a tick till that happens. Frams have a weak ADBV and sometimes people will get a start up tick using them for this reason.

 

GM specs a filter with an ADBV for a reason. The engineers for the aftermarket filters makers do also...

 

This is an old post from out late and great friend...C&As Dad who sold filters..

 

I am no engineer when it comes to this but I will tell you what I have been told by the engineer at Wix that I know. The AD valve is important on certain engines no matter how the filter is mounted. On our engines and others with the filter mounted upright, it allows oil to remain in some of the passages where it would otherwise drain back.

 

Again, I asked this same question and was told that if it is designed in from the OE, it is vital that it be there.

 

 

 

 

Okay, now I'm confused. When I open the oil filter boxes at Wally World, I can see the orange rubber anti-drainback gasket 'valve' on the Fram TG10060. But I don't see any such thing looking at an AC Delco PF-48. Are you guys talking about the filter brands in general, and our specific GMT900 AC Delco filter just doesn't happen to have an anti-drainback valve?

[dlstewart01]

Mostly normal, but a quick question about what oil filter your using. Does it have the anti-drain back valve?

 

 

I would figure that if the oil filter was vertical, gravity would keep the filter full making an anti-drainback valve unnecessary.

 

 

Its not the oil in the filter you need to worry about. its the oil above the filter in the passages. When you take the filter off see how much oil runs out. If you don't use a filter with an anti drain back valve this oil will drain from these passages and when you start the truck these passages will have to fill up before you have oil pressure and you may get a tick till that happens. Frams have a weak ADBV and sometimes people will get a start up tick using them for this reason.

 

GM specs a filter with an ADBV for a reason. The engineers for the aftermarket filters makers do also...

 

This is an old post from out late and great friend...C&As Dad who sold filters..

 

I am no engineer when it comes to this but I will tell you what I have been told by the engineer at Wix that I know. The AD valve is important on certain engines no matter how the filter is mounted. On our engines and others with the filter mounted upright, it allows oil to remain in some of the passages where it would otherwise drain back.

 

Again, I asked this same question and was told that if it is designed in from the OE, it is vital that it be there.

 

 

 

 

Okay, now I'm confused. When I open the oil filter boxes at Wally World, I can see the orange rubber anti-drainback gasket 'valve' on the Fram TG10060. But I don't see any such thing looking at an AC Delco PF-48. Are you guys talking about the filter brands in general, and our specific GMT900 AC Delco filter just doesn't happen to have an anti-drainback valve?

 

 

AC Delco filters are made by Champion Labs. The last time (a couple months ago) I spoke with Champion Labs, they told me they DID NOT make an AC Delco filter with-out an anti drain back valve. The AC Delco filters ADBV is made different, (E-core design) it also functions as a BY Pass valve in case the filter gets stopped up it will by pass the filter so you still have oil circulating through the engine...

[07 GFX Silverado]

My truck does the same thing, sometimes it lasts for 1-2 minutes.I use synthetic oil and it does not help. My truck actually burns about a litre of oil every 3000 kms and they(GM) tell me that this is normal. Even when I let my truck warm up and leave work, hit the throttle and it leaves a cloud of blue black smoke behind me. I say bring back the 5.7 ltr as it was a great motor.

[rodram]

It is a terrible thing that you '07 and newer 5.3L AFM engine owners have to deal with this oil consumption issue.... GM is just starting to accept that there is an AFM-related issue and is monitoring oil loss..

 

and yes, the 5.7L was a pretty good engine, even though it had it's own weak points...

I will be keeping my 5.7L in my '97 for as long as it is practical to maintain this thing...

 

My truck does the same thing, sometimes it lasts for 1-2 minutes.I use synthetic oil and it does not help. My truck actually burns about a litre of oil every 3000 kms and they(GM) tell me that this is normal. Even when I let my truck warm up and leave work, hit the throttle and it leaves a cloud of blue black smoke behind me. I say bring back the 5.7 ltr as it was a great motor.