What Diff??

[Stephen22]

Hi guys, with my Datsun 510 the guy gave me a diff. 

Can you please help me identify this diff??

 

[thisismatt]

It's an R160, same as stock.  No way to tell what the internals are.  You can figure out the ratio by number of turns, and you can check if it's a limited slip (or welded) by turning one output stub and seeing if the other turns the same way (if the other turns backwards than it's open, like stock).

[Stephen22]

Thanks. My current diff is welded and I really do not enjoy it. So I will replace it with this diff and see how it goes.

 

[datzenmike]

Pop the rear cover off. The ratio is stamped on the outward facing edge of the ring gear and non LSD will be obvious. 39:10 is 3.889 and 37:10 is 3.70.  LSDs are a two edged sword and welded diffs are scary dangerous.

[Tedman]

38311 21100 pn cast into top of case indicates a stock 510 R160. What Mike said about id'ing ratio.

[datzenmike]

Used on 2 and 4 door 510 and 610 sedans through July '73.

[Stephen22]

Thanks guys. I am going to fit this diff back, the welded diff is terrible. I just hope it lasts. 

[Stephen22]

I removed my diff that was welded. Can anyone tell me what diff this one is?

I thought it was the same as the ones in the photos above but its slightly different.

 

[datzenmike]

There's bound to be some revisions over the years and Subaru uses the same R-160  in their cars.

 

 If the ratio is the same and the carrier fits... just swap it entire. If swapping the internals you really need to have the gear lash set by an experienced tech.  You can (but should not) just bolt it in if you want long life out of it..