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Rear Diff code (on diff)??

1K views 4 replies 2 participants last post by  Rod's Trucks 
#1 ·
I have an extra rear diff, with the dot matrix code, on the axle, of AM3(?). Is that a valid code for a rear diff? The doors, and most everything else, were gone off the van it came out of. I was given the diff for the privilege of carrying it off the property.
I may be reading it wrong, but that AM3 is the best guess I can come up with, after wire brushing and cleaning.
I've looked several places and cannot find that code, but I have not found anything that listed the codes after about 1998.
It is an open diff and I am pretty sure it is a 3.42 As I recall, it came out of a Gen 2
Any suggestions as to what code that might have been, or if it is a legit code, what does it tell me?
Thanks ?
Rod J
 
#3 ·
Thanks for the info. Where did you find that?

Well, if the AM3 is a good code, then maybe it is a G80. I recall the van that donated this diff was newer than mine, and I was told it was fairly low mileage, so the 96-2000 years makes sense.
I have had no reason to open it up....until now.
I have no use for a 3.23 G80. I have 3.73 gears and AWD.
Rod J
'98 Forest Green Astro
 
#5 ·
A long time coming, but....
Today I got really curious about these extra rear diff's I have had sitting in the bushes. I went after this one with wire brush and solvent. The code is definitely a AM3.
(The other is an older Gen I 'UTR' 3.73 open)
I opened up the ?? diff. It is a 3.42 open diff. It has the slightly narrower spring perches, so the Gen 2 style steel springs were likely on the chassis it came from. I am thinking it was a 2000 cargo that it came from, so that all makes sense.
It is possible, if is was originally a AM3 G80, the G80 had done what they are known for often doing (breaking), it was replaced with an open diff.
End of mystery...sort of :confused: !
So I have a spare 3.42 front and rear, set probably off the ~2000 cargo; and an earlier 3.73 rear

Rod J
Issaquah, WA
 
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