rear diff

Hi , what size is the rear end in my 99 ws6 ? 7.5 ? or 8.5 ?
thanks

7.5

7.5

Cool, so what interchanges with it ? and what are the GM codes for gear ratio ? so is the s-series truck the same center section ?

What do you mean by interchanges with it?

GU2 - 2.73
GU3 - 3.08 v6 gear
GU5 - 3.23
GU6 - 3.42

well mine howls , I can't find any in my area , but I have a s truck with 3;73 , in it and it's a 7.5 , 31 spline , ? so will the guts fit ?

When I had my 98' TA the rear would randomly howl at low speeds.Like when driving around a parking lot.

I changed out the fluid and never had a problem after that...

Just a thought,hope you get your situation worked out.

if its howling it could also be a bearing. drain the fluid and see if there are any metal shavings