8.5 code identification HELP!

[SuperCutlassGT406]

Recently picked up an 8.5 rear end and can't find out exactly what it is. I've found the codes but can't seem to match them to anything. The code is a little worn but I believe it says

9TP G 143

Any help would be much appreciated

 

[Ribbedroof]

TP is a 3.42 limited slip

G is the plant (Detroit gear and axle)

143 is the Julian date of assembly

 

[SuperCutlassGT406]

It is a 3.42 but it's a posi

 

[SuperCutlassGT406]

Oops you said that lol

 

[SuperCutlassGT406]

Any idea what it's out of?

 

[SuperCutlassGT406]

I got it out of an 83 cutlass but I assume it wasn't original

 

[Ribbedroof]

I got it out of an 83 cutlass but I assume it wasn't original

That's a given, since the G body 8.5 was not available prior to the 1984 model year

I would guess a GN as they would have been produced in higher numbers than the other possibilities...and 3.42 being the standard gear for them

 

[pontiacgp]

by this chart TP is an open carrier.....but since the rear end is about 30 years old who knows what changes have been made to the gearing

 

[SuperCutlassGT406]

Thanks!

 

[Ribbedroof]

I noticed that too, but it contradicts every other source online