Aluminium 4 speed case strength

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GTXS
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Aluminium 4 speed case strength

Post by GTXS » Mon Sep 24, 2012 4:29 pm

I am thinking about taking all the 18 spline parts out of the old cast iron housing and having it put into a later model aluminiul housing. My only question is would it be strong enough. I'm thinking about shaving a few pounds here and there.

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471Magnum
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Re: Aluminium 4 speed case strength

Post by 471Magnum » Mon Sep 24, 2012 7:23 pm

Short answer: NO
-Jim
"I can fix it... my old man is a television repairman... he's got the ULTIMATE set of tools... I can fix it."
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gcoupe72
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Re: Aluminium 4 speed case strength

Post by gcoupe72 » Wed Oct 03, 2012 9:55 am

GTXS wrote:I am thinking about taking all the 18 spline parts out of the old cast iron housing and having it put into a later model aluminiul housing. My only question is would it be strong enough. I'm thinking about shaving a few pounds here and there.
I think it depends on which case you're talking about.
You said later model, do you mean overdrive?
Steve Dulcich did a story in mopar muscle mag. quite a while ago about putting steel inserts into one of these housings for strength, and to correct worn holes. I think I'd pass on this with a big block!
There is an aftermarket aluminum housing that I think has been beefed up in know weak spots that would probably be ok, wonder if anyone on the nest has any experience with this?

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471Magnum
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Re: Aluminium 4 speed case strength

Post by 471Magnum » Wed Oct 03, 2012 10:08 am

Those aluminum cases were conceived to run behind slant 6's. Their durability was marginal in that application.

The casting is virtually identical to the cast iron, with no compensation for the reduced strength of aluminum.

The Passon case is the way to go if you want to drop the weight, but it is a very expensive diet plan.
-Jim
"I can fix it... my old man is a television repairman... he's got the ULTIMATE set of tools... I can fix it."
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