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finned diff cover question


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Maybe some of you guys might know this....

Some subies I see have the smooth rear diff cover, and some like mine(99 OBS)have a finned diff cover. What is the difference besides cooling? Or is there a difference besides that? Just curious, as I can't seem to find a definitive answer on this. Thanks!

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I dunno, lol. I'll get a pic of mine tomorrow. It's bone stock on my 99 obs. Pretty sure all these were open diffs. At least mine is or acts like it. Tires spin opposite when off the ground, no indication of a lsd in there whatsoever. I'm pretty knowledgeable with drivetrain stuff, so I know what to look for with that kinda thing.

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When I was heavy into the early Fox Mustangs, some aftermarket covers being sold were actually designed to increase the rigidity on pumpkin area. Some of those had internal sections that helped strengthen the main cap areas.

 

 

Without seeing the inside of the finned pumpkin cover, it appears to be mainly for better heat transfer and some rigidity increase. As long as some air IS moving across the fins (hard to say if air is moving or stagnant around here given how airflow UNDER a car doesn't always do what you think it should) it'll greatly help with lowering oil heat. So this would be an upgrade and help keep oil cooler under towing or hard off roading, etc.

 

Also, even if the the inside of the cover doesn't add any sort of extra support for the main caps, the fins WILL add some structural strengthening to the entire assembly. Probably not going see full benefit on a stock-powered car, but on higher HP it'd definitely help in one way or another. And having it dissipate heat more efficiently than a smooth, stamped steel bowl cover, longer life should be the norm. 

 

And hey, remove it, polish the hell out of the aluminum and the bolts and you'll have a cool looking pumpkin cover.

Edited by Bushwick
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