what tool for rear diff?

[1Gina2G]

what tool is needed to get to the oil fill bolt on the rear differential? none of my tools can seem to reach the bolt without getting in the way with some kind of line, maybe a brake line?

 

[95eclipseguy]

If i'm reading your post correctly, you simply want to fill/check the level of lube in your rear diff. I have 3 GSX's and all have a plug in the case cover on the back of the diff that takes a 17mm wrench. The only thing in the path should be the sway bar, but you should be able to get to it easy enough. However, it will be tight!