Slight Knocking noise after oil change?

Hmong_1G

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Dec 31, 2008
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California
Ok I hope it's nothing serious, but my passed down supra ( from my dad) has been on conventional Castrol 10w30 as long as my dad had owned it. He rarely does oil changes on time. I just changed it out For Royal Purple and after starting it up... it idled and ran fine. After it reached its operating temp, I can hear a knocking noise from under the Intake manifold. WTF? Is this because the use of synthetics or a more horrible reason. This noise gets alittle louder, but not much with revs. Oil pressure does go down at normal temps. Is this a normal 7mgte noise? I've searched around and looked at many other posts.... but I really hope its normal. Please someone enlighten me.


sorry for the rather longish post.
 

hvyman

Dang Dude! No Way Man.
Staff member
Apr 17, 2007
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syn is not going to affect it. wat rp did you use 5w30 or 10w30? either way there all still a 30w at op temps. sure you just dont have something loose down there? what is your oil pressure at idle and at 3000rpms hot? where exactly is the noise oming from front rear? need some more info.
 

Hmong_1G

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Dec 31, 2008
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California
Don't flame me but I'm doing my measurements of the stock gauge. I know its not as accurate, but at 3k the psi jumps up to wat I believe is 15-20 mark. Its hard to tell you all, but I think oil pressure is fine, but this knock seems right under the intake manifold. I thought 7mgte is a hydraulic valvetrain? I'm running 10w30 RP. At 3k the noise is a little more faint but there. It's weird because this noise becomes noticeable at normal operating temp. On start ups (cold) the knock isn't there. Thanks guys for the fast responses.
 

gaboonviper85

Supramania Contributor
Jan 13, 2008
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Northeast Philly
Hmong_1G;1350728 said:
Don't flame me but I'm doing my measurements of the stock gauge. I know its not as accurate, but at 3k the psi jumps up to wat I believe is 15-20 mark. Its hard to tell you all, but I think oil pressure is fine, but this knock seems right under the intake manifold. I thought 7mgte is a hydraulic valvetrain? I'm running 10w30 RP. At 3k the noise is a little more faint but there. It's weird because this noise becomes noticeable at normal operating temp. On start ups (cold) the knock isn't there. Thanks guys for the fast responses.

no a 7m does not have lifters...we have shim buckets which suck royal ass and valve adjustments are a whore!

also....10w30 royal purple is too thick on cold start ups.....you really should have went with 0-30....
 

GC89

1J-THIS
Jun 13, 2007
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Spokane, WA
I would also recommend a different oil 5 or 0-30, preferably 0. Try crawling under the car when it is running see if that gives you a better Idea if its coming from the pan or something else.
 

Hmong_1G

Name the Place and time.
Dec 31, 2008
280
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California
Alright guys... thanks for the advices. I haven't got a sethoscope avalible, but will check into it sooner. I checked the crank and seems on tight and perfect condition. I'm still on the stock injectors. Funny thing is this happen after I did the oil change. WEIRD.... :aigo:LOL.


My next oil change i'll go 5w-30. This 7mgte is still all original with 178,xxx miles. :biglaugh: