pinkpanthr
Well-Known Member
Looked through the older topics and haven't been able to get a clear answer, so can anyone tell me how to identify whether my center section is a 489 or a 742? Thanks in advance.
....... I have 3 -742s, 2-741s and 2-489s with different gear sets :basketcase:
The 489 was thought to have the strongest pinion gear but that has been questioned as of late. They came with a cone style limited slip if equipped which can be tightened up with some machine work, the earlier ones had replaceable clutches. And the crush sleeve on the pinion can be replaced with a spacer now. I don't know where they came from, they are like mushrooms I have 3 -742s, 2-741s and 2-489s with different gear sets :basketcase:
No wonder the rest of us can't find any rear ends. LOL! Do you have a different ratio for each of the carriers? Do you find it easier to change the whole axle or just the carrier. Is there a Sure-Grip available for a 741 case? Sorry for the questions but always have been curious on these issues
Hoarder. :acme:
Don't figure on the sure grip unit corresponding with the casting number on the center section. Lot's of stuff gets swapped over the years.... and even if it's never been out of the car, you never know what was installed in that axle on any given day.
Hoarder. :acme:
:toetap: :toetap::toetap::lmao::lmao::lmao:
I have a 742 case with a 3:55 open rear. The reason I asked is because I'd like to go to a sure grip rear with probably 3:23's. Just wanted to make sure there wasn't anything special I would have to look for.
I'm curious why you would want to downsize from the 3:55 to the 3:23's , most people on this sight and elsewhere all seem to want the higher gear ratios .
Also , you said you had an open rear . Is that the setup the car came with ?