im replacing the master cylinder on my 90. when i looked at the new one in comparison to the one on my car now, theres a slight difference. the new one has what looks like a grease fitting for a suspension component on the side of it. is this some kind of bleeder valve that my old master cylinder doesnt have? all other bolts and brake lines line up to the new one. anyone know what it is??

Did you get a brand-new one or a rebuilt ($20) one?

dunno, i think its new. it was $45 with a core exchange....... the shape is slightly different so im going to say its new.

If they wanted a core, it's probably a rebuild. (New would be around $150) I've never seen anything like that... I might be wrong, but I'd be thinking that you got the wrong part. Is there a name and part number on the box that we can look up for ya?

(You could see if you canfind it yourself, too, from http://www.carparts.com or http://www.partsamerica.com or http://www.expressautoparts.com or http://www.rockauto.com - I try to always check these sites for part #s before I go to the local auto parts store.)

this is what i bought:
Master Cylinder

Oh, wow, A1-Cardone changed their part numbers? Used to be that 10-2057 was for J50 (disk/drum) and 10-1997 was for J65.... oh for cryin' out loud. I'm an idiot. Partsamerica.com is just leaving out the dash between the numbers.

So that is the right part #... any way for you to get a picture up of that spot?

found out what it is. turns out its a bleeder valve so you don't have to bench bleed the cylinder. kinda cool.......

thanks for all your help tom

Hey no problem, thanks for the info on what that thing was! That -is- pretty cool, be sure to come back and let us know how it works out!!