'63-'79 Eaton diff rear cover bolt length/pattern same as '80-'82?
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'63-'79 Eaton diff rear cover bolt length/pattern same as '80-'82?
Can I use the same rear cover bolts that are on a '68 Eaton to mate it to an '80 batwing? Should the length be the same? Is the pattern the same?
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
The pattern is substantially the same, so the batwing will bolt up just fine. There's a couple bolt holes in the lower corners that aren't used if you bolt the batwing to an iron case.
I can't definitively answer the bolt length question. I suspect the batwing is just a touch thicker, but it's probably insignificant. Just stick a screwdriver in the holes and compare the depth to the bolt length.
I can't definitively answer the bolt length question. I suspect the batwing is just a touch thicker, but it's probably insignificant. Just stick a screwdriver in the holes and compare the depth to the bolt length.
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Both.
Going by memory here: The two pairs of bolt holes in the batwing at the 5 and 7 O'clock locations don't match up with the iron case. Just ignore them. Not a problem or issue for gasket sealing.
The iron cover uses 8 bolts. When using the batwing on the iron case, you use six bolts. The two bolt holes at 4 and 8 O'clock in the iron case/cover aren't used with the batwing. (There's a big thick web at that location.)
I ran several years and a lot of track miles with the C3 batwing on my iron case differential with no problems. (A couple years ago I swapped out the C3 batwing for a lighter (and modified) C4 batwing to get another 5# of weight off the car.)
Going by memory here: The two pairs of bolt holes in the batwing at the 5 and 7 O'clock locations don't match up with the iron case. Just ignore them. Not a problem or issue for gasket sealing.
The iron cover uses 8 bolts. When using the batwing on the iron case, you use six bolts. The two bolt holes at 4 and 8 O'clock in the iron case/cover aren't used with the batwing. (There's a big thick web at that location.)
I ran several years and a lot of track miles with the C3 batwing on my iron case differential with no problems. (A couple years ago I swapped out the C3 batwing for a lighter (and modified) C4 batwing to get another 5# of weight off the car.)
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Originally Posted by brassplyer View Post
Bolt holes on the diff case or on the batwing that aren't used?
Bolt holes on the diff case or on the batwing that aren't used?
Going by memory here: The two pairs of bolt holes in the batwing at the 5 and 7 O'clock locations don't match up with the iron case. Just ignore them. Not a problem or issue for gasket sealing.
The iron cover uses 8 bolts. When using the batwing on the iron case, you use six bolts. The two bolt holes at 4 and 8 O'clock in the iron case/cover aren't used with the batwing. (There's a big thick web at that location.)
I ran several years and a lot of track miles with the C3 batwing on my iron case differential with no problems. (A couple years ago I swapped out the C3 batwing for a lighter (and modified) C4 batwing to get another 5# of weight off the car.)
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
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Originally Posted by brassplyer View Post
It seems I read something about having to take some metal off either the iron diff case or the batwing for it to fit - do you recall having to do that? Is there some part of the iron case that bumps into an area on the batwing?
It seems I read something about having to take some metal off either the iron diff case or the batwing for it to fit - do you recall having to do that? Is there some part of the iron case that bumps into an area on the batwing?
All this is theory so far, I haven't gotten to the point of pulling out the Dana and trying to put the Eaton in place. I've got all the pieces except the driveshaft and whatever U-joints the Eaton will require.
