When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
The attached link is for a posi-diff and gears out of a S-10. I was wondering if it will fit my 1985 Z28. Thank you in advance for your input.
Respectful Regards,
You don't want a Gov-lock. Your 85 should have 26 spline axles, if it even has a 10-bolt. Doublecheck that it doesnt have a 9 bolt before you buy parts.
I agree, you do not want a Gov Lock. Look up Quick Performance on ebay and get their package with the Yukon Dura Grip, gears and USA Standard installation kit.
Thanks for the reply. I have to gather more information.
Check the number of bolts on the diff cover. If it's 9 you need the Torsen carrier from Australia. I have a post about those in this forum section. If it's 10 bolt you want Big Head Gear mentions above.
Thanks I will check it out in a couple of days. In addition to the differential cover, I will be looking over the axle tube for a gear code.
I have only owner the Z28 for a month and have already done a heads and cam (25 hour thrash!!!). Exhaust is next and then a 3:73 gear.
Still has greasy hand prints from the weekend.
Assuming you have the 7.5 10 bolt, you need to pull the axles out before you order any parts. If the axles are worn where the bearings run on them then you need to replace them too. No point in putting 26 spline axles and differential in it when 28 spline parts cost the same and are quite a bit stronger. Now is the time to upgrade.
Assuming you have the 7.5 10 bolt, you need to pull the axles out before you order any parts. If the axles are worn where the bearings run on them then you need to replace them too. No point in putting 26 spline axles and differential in it when 28 spline parts cost the same and are quite a bit stronger. Now is the time to upgrade.
Exactly when I rebuilt my diff there was zero difference in price between the 26 and 28 spline carrier and the 28 spline axles were actually a little cheaper.
Except that Auburn just told me last week that the weak link in these rears is not the axles -
it's the small diff side gears and the small ring & pinion.
The pinion gear gets really small if you have 4.10s.
Ring & pinion usually goes first in the 7.5, but no point in putting 26 spline parts in if you have to replace them anyway. 28 spline stuff is the same price and stronger. I'd rather be sure that the gears are going to break before the axle. When the ring & pinion break it doesn't tear the quarter panel off and cause you to crash.
Yeah the 2 pinion side gear design is much weaker. But if you get a Torsen carrier there's no side gears anymore.
GM used the same diff on the 99 to 02 WS6 with LS power, T56, and zexel torsen carrier. They can hold decent power. It's no drag race diff.
The 9 bolt can be upgraded to the same or a little higher power. They have 28 spline axles already, larger ring gear, and a more rigid case design. The Torsen carrier for them is about $500 shipped from Australia. You can get 370 gears easily. Other ratios from Australia also. They get used on 500 wheel HP commodores over there routinely and are pretty well respected.
TA makes a girdle cover for them.... etc.
People talk a lot of trash on the 10 bolt, not as much, but still on the 9 bolt - realistically what power level are you going to be at?
Ring & pinion usually goes first in the 7.5, but no point in putting 26 spline parts in if you have to replace them anyway. 28 spline stuff is the same price and stronger. I'd rather be sure that the gears are going to break before the axle. When the ring & pinion break it doesn't tear the quarter panel off and cause you to crash.
That is why I did mine, my old axles were worn on the bearing surface after 32 years of use. No reason to not upgrade
The axles on the 9 don't don't wear like that either. They are Timken tapered roller bearings pressed onto the axles making the axle not a wear item. Also they are retained by a heavily interference fit sleeve and a bolted retainer plate making them "clipless" and they will not fly out of the axle tube if they should break. Basically they are stock with C clip eliminators.
Ring & pinion usually goes first in the 7.5, but no point in putting 26 spline parts in if you have to replace them anyway. 28 spline stuff is the same price and stronger. I'd rather be sure that the gears are going to break before the axle. When the ring & pinion break it doesn't tear the quarter panel off and cause you to crash.
03-28-2017, 09:14 AM
