New down pipe came in black grease inside?

Probably a stupid question but just got my catless downpipe in the mail today when I opened it up I noticed a black grease like substance inside top portion with some metal shavings. Looked like something from maybe the welds and not cleaned after properly?! And ideas guys? Of course didn’t take a pic

Here’s pics of the residue on the towels after cleaning

its used prior. that's carbon soot.

CalvinL said:

its used prior. that's carbon soot.

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Gotcha that’s what I figured was something from the welding process

CalvinL said:

its used prior. that's carbon soot.

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Agree...

Sauceii said:

Gotcha that’s what I figured was something from the welding process

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I don't think that's from the welding process...It appears that's carbon exhaust soot as the result of having been installed on a another Supra ...most likely a returned downpipe was simply resold ....

tadda said:

Agree...



I don't think that's from the welding process...It appears that's carbon exhaust soot as the result of having been installed on a another Supra ...most likely a returned downpipe was simply resold ....

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It definitely was never installed on another Supra I’ll post some more pictures . Looks to me like weld smut and from my small understanding of welding that’s when gas shielding becomes marginal and the aluminum and magnesium are being oxidized

Sauceii said:

It definitely was never installed on another Supra I’ll post some more pictures . Looks to me like weld smut and from my small understanding of welding that’s when gas shielding becomes marginal and the aluminum and magnesium are being oxidized

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tadda said:

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Here’s some updates pictures I tried to mark the areas where the substance was in red . You can see the wipe marks from me wiping it out with the rag

tadda said:

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Tried to get another shot from the other end as well . It seemed it was in the area the o2 housings were welded in . Figured to post up in case some master welders could explain better . I’m 99% positive it was never installed on another Supra though as it was only about a 3inch ring around the o2 housings area

Looks newish to me