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Discussion Starter #1
Hi guys, I've noticed that the first start after an oil change results in something sounding like rod knock in the '94 4.6 Tbird.

It goes away after a few seconds. I'm assuming this is an oil pressure problem? However, our 94 Crown Vic w/ the same motor never has done this after an oil change. I have tried both a dry filter and pre-filling the filter.

It also makes a different knocking noise upon startup when cold. The after oil-change noise is more muffled. However, the engine runs awesome outside of this.

I always use Motorcraft oil filters and have tried different oils including MC 5w-30, 10w-30, pennzoil 10w-30, and Castrol 10w-30. The engine still makes the noise.

Any suggestions? I'm stumped and I'm hoping its not major.
Adam
 

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The knocking after changing oil is normal, every car I owned has knocked after changing the oil and filter. On my T-Bird I disconnect the coils and crank the engine over for 10-15 seconds and then hook the coils up again and start.
 

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Discussion Starter #5
Ok, I might try that. I just don't like it and it makes me cringe :p
 

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Mod motors all have verry tight tolerances, and its common to have a bit of clanging around on cold start or after changeing oil... the only cure for this is 5-w20 Mobil one, and sometimes that doesnt even work.motorcraft filters are recommended also... however taking it easy for a few minutes after start up, and there shouldnt be a problem even if it sounds like he11 for a few seconds, go figure
 

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Discussion Starter #7
Ya, I was thinking along the same lines so I switched from Dino 10w-30 to Motorcraft Synthetic Blend 5w-30. Oh well.
 
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