Does anyone happen to know what these numbers mean?

 

"287" is the matching number with the pinion in that transmission. They are a matched pair.

"08/84" is the production date.

"75.00" is the pinion depth

"020" is the backlash in 100ths of a millimeter.

 

So, this probably came out of a 84?
And i will need to swap pinion gears?

 

what year are you installing it in? you can use the RP you have now.

 

It's going in a 86 5 spd.

 

Thank you!
This will be very usefull for my future ring and pinion swap.

 

It's all explained in WSM.

 

Ring and pinions are matched pairs....never to be separated or run with another piece from another set!

If you change the differential in any transmission, both the bearing preload and the backlash will need to be adjusted, because the differential housings vary in distance between where the two bearings set and where the ring gear sits.

So, use the ring gear off of the '86, bolt it onto this limited slip (after rebuilding the limited slip), and set-up the preload and backlash.

Note: It is possible to very accurately measure the two differentials and set up the preload and backlash, assuming the '86 transmission is intact, properly set-up, and in good condition....I do this on a routine basis.

 

Thanks Greg,
The '86 transmission is in good condition....(74,000 Granny driven miles).
That's exactly what I was hoping I could do.
I may be able to get the pinion from the donor transmission.
Would that be a better way to go?

 

To change the pinion gear in a 5 spd you must take the transmission all apart.....the automatic has a short "bolt on" pinion gear to mate to the Mercedes trans. Very different pinion gears.
You need to run your current r+p .... rebuild the slip with new friction discs and correctly set up the mesh dimensions.

 

Makes sense.
That's my plan then.
Thanks James.

 

No!

Switching the ring gear and setting it up is relatively simple. Installing a pinion requires completely disassembling the transmission, swapping the pinion shaft, then setting up the new pinion depth, and then still needing to set up the preload and backlash of the differential.

Way more work!

 

Gotcha.
It did seem like the long way to go.

 

More help please.
Got my LSD today.
More numbers....what do these mean, if anything?
4061006320 26599 S40

 

Side question for the collective: is this a four or eight disk lsd? Unsure what MY the change was, did they change from eight to a four when the synchros were upgraded? Any why?