131mirafiori forum

I've got a 132 disc rearend in my 131, the only issue is the 4.1:1 (10:41) ratio, it's too short for my liking. I've been told the auto Argenta had 3.417:1 (12/41). Does the Argenta rearend bolt up the same as the 132, ie: 2 parallel lower control arms and 2 angled upper control arms? Would the Argenta CW&P fit the early 132 housing?

When I did the diff swap in my 131 I was told that Argenta is the easy way to go.
Try getting one now.  Are you able to get one ?
The ratio is still off a bit.
I used holden 3.55: 1.
You could also use ford 3.5 : 1. There would be more machining in the ford diff conversion, like axle splines but for the dedicated there is no limit. Prop shaft to pinion flange is the same work either way.
As to the suspension arm mounts, cutting & welding fixes that issue.
Really all you need look for is track width & ratio. Who knows even a Toyota diff is in Sids 131.
If you cannot do the engineering yourself you are going to needa the spondoolie.
O.
P.S.  Look for something real common for ease of repair at any future time.

Anything can be made to fit, something from the Fiat parts bin is the least painful.

I think the 132 and Argenta arm to axle mounts are the same, just the axle should some 2cm wider.
Argenta VX had also the 3.417 ratio and a 2.5TD version had the longest gearing known to me, 3.15:1
132 2000 GLS Automatic also had 3.417.

The Argenta I'd been told about has been crushed unfortunately.

Now what ?
Are you going to live with the diff that you have ?
O.

I've got 2 x 131 rearends behind the shed, 3.58:1, I might look at putting the 132 discs on one of them.