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^ he thinks heavier oil is the culprit.
 
Discussion starter · #2,163 ·
Yeah, since I switched to a lighter oil the knocking/slapping has since became shorter.
 
Heavier oil just puts more load on the bearings anyways...unless you're revving the shit out of your car all the time. It's useless.


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Discussion starter · #2,165 ·
AND by me adding that thick molasis Lucas oil additive, it seemed to make things worse :facepalm:
 
Discussion starter · #2,167 ·
It’s the bearings, the noise is coming from within the center of my engine. I’ve listened to it with my stethoscope and you can even hear it from inside the car. The lighter oil help get into the tighter spaces (bearings) on cold starts. The thicker oil and the even thicker Lucas oil made it too difficult in lubricating the bearings.
 
That sux.. Dude you dont need to use a stethoscope. Your not a Doctor for God sakes, your a part time mechanic! :curse: Do like I do, use a prybar with a plastic handle to listen to all the crazy sounds coming from within that beast! :projectsti.com:
 
All this talk about engine noises makes me super paranoid with my engine. I literally started my car today, then got out with my ear to the hood trying to figure out whats going on under there lol

As of right now I dont have a knock per-se, just a kind of "shssh, shssh, shssh" noise with a light whine which i think is probably one of the timing belt idlers, never been replaced yet :/
 
Discussion starter · #2,170 ·
^ :lol:

Well, the thing is that I’ve had this car for a long time and it has gone through such a drastic transformation from being a comfortable (boat like) grocery getter to a some what stiff and agile street and track machine.

After adding little by little all of the bushings and stiffer mounts, you begin to hear new things each time (NVH). Only after I added the stiffer group-N engine mounts is when I noticed the slight knocking. Its such a treat to hear your engine make all kinds of sounds and noises from inside the car when you racing it and just driving it on a daily basis.
 
Discussion starter · #2,171 ·
Here is the update on the oil change. It works! :banana: The Shell Rotella synthetic 5W-40 motor oil really did do the job in getting the knocking time down to a super short period. Here are some stats from the quick log I took:

(note: all "warm up temps are when I couldnt hear the knocking anymore ;))

Before oil change (running Castrol GTX high mileage 10w-30, roughly 2000miles on oil)

engine start temp: 58F time: 9:42pm
engine warm up temp: 130F time: 9:46pm

engine start temp: 66F time: 9:39pm
engine warm up temp: 114F time: 9:43pm

After oil change (switched to T6)

engine start temp: 62F time: 9:42pm
engine warm up temp: 75F time: 9:43pm

engine start temp: 57F time: 7:36am
engine warm up temp: 94F time: 7:37am

As you can see that the T6 lighter weight oil only took about a minute for the knocking to go away Vs. the GTX time of about 3-4 minutes of idling.
 
Discussion starter · #2,173 ·
I think its just the lighter oil thats helping. But they say that full synthetic has good wear properties.
 
Discussion starter · #2,174 ·
But everyone Ive talked to swears by the Rotella oil, so I thought I would give it a shot ;)
 
5 subaurs and i only use castrol gtx regular. 15.50 for 5 qts at the wal
 
Just changed my oil today, castrol sytec 5w30 for me, great oil my only complaint is if you let it sit for too long the oil is so thin it seeps past the gaskets. Other than that it is good, and usually still somewhat clean after changes.
 
The engine warm up temp between the two is a huge difference.
 
Discussion starter · #2,179 ·
I only had to use one big bottle. There is still a tad left over too.
 
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