Is this an Aluminum or Magnesium trans case?

[davewadd]

I don't know how to tell the difference between aluminum and magnesium on a transmission case. This is a 911/01 trans. Can you tell if it's aluminum or mag?
http://forums.pelicanparts.com/porsc...ld-so-cal.html

[Cliff]

Mag, for a 70/71 b4 the 915 trans & after the original 901/902 aluminum cases....

[davewadd]

so does that mean all 911 transmissions are mag? Is one more desireable than the other?

[M_deJong]

I think there was aluminum 901 thru 68, then mag 901 '69 push clutch, then '70/71 911 mag pull clutch.

Aluminum a bit stronger, magnesium a bit lighter. All depends on what's important to you.

[beh911]

Transmission cases switched from alum to mag mid MY 69

[davewadd]

Is there a way to tell? Part number maybe?

[mike curnow]

Just look at it, aluminum is silver magnesium isn't.

[beh911]

Well, a 911 transaxle type is a 70+ case, so it should be magnesium.

[davep]

Is there a way to tell? Part number maybe?

Sure, that is easy, the AL main case has casting 901.301.101.0R and the MG case has casting 901.301.101.2R

[davewadd]

Dave P....this case has 901.301.301.1R as seen in the photo above. Not one of the options you listed.