Differential Fluid Change
Thread Starter
Racer
Joined: Nov 2018
Posts: 289
Likes: 105
From: Missouri
Differential Fluid Change
I have a Superformance 1963 Grand Sport and want to change the diff fluid. There are 3 plugs on the passenger side of the diff. I think the top one is for filling/return from cooler, the middle one is for send to cooler, and the bottom one is for draining. Can anyone confirm this?
Cheers,
MrHix
Cheers,
MrHix
Race Director
Joined: Feb 2007
Posts: 15,481
Likes: 8,960
From: northern california
C2 of Year Finalist (track prepared) 2019
You'll get the best answers if you provide pictures of the differential area and of the plugs you mention.
For that matter, does your Superformance GS use a C4 differential or a C2 differential?
For that matter, does your Superformance GS use a C4 differential or a C2 differential?
Race Director
Joined: Feb 2007
Posts: 15,481
Likes: 8,960
From: northern california
C2 of Year Finalist (track prepared) 2019
The cover is a custom casting by Superformance and is intended to resemble the covers used on the original Grand Sports. The tube frames are similar to the originals but miss on some important details.
Race Director
Joined: Feb 2007
Posts: 15,481
Likes: 8,960
From: northern california
C2 of Year Finalist (track prepared) 2019
I have a Superformance 1963 Grand Sport and want to change the diff fluid. There are 3 plugs on the passenger side of the diff. I think the top one is for filling/return from cooler, the middle one is for send to cooler, and the bottom one is for draining. Can anyone confirm this?
Cheers,
MrHix
Cheers,
MrHix
Assuming so, the bottom one would be the drain. The fill plug will be found on the passenger side of the iron differential case.
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Michael S. Palmer
Tech Contributor
Joined: Aug 1999
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From: Connecticut, USA
I'm only going to guess here, but the originals had taps for oil cooler lines. I suspect that cover has the same with the fill plug above it- as you think. I would have tapped the bottom of the housing for a drain as I have for 100's of them so far. Makes it a lot easier to change the hole at the lowest point. I think if you pull the lower plug you can drain most of the oil out.