View Full Version : 10 Bolt Gears

03-11-2006, 09:54 PM
Does anyone know if the carrier has to be changed when swapping from 3.73 to 4.56 on 88' GM 10 Bolt front and rear axles?


03-11-2006, 11:03 PM
yup 4:10 is the changing point

03-12-2006, 12:28 AM

Split on a 8.5" 10-bolt is 2.56/2.73.

Same case (carrier) for 3.73 to 4.56.

03-12-2006, 11:36 PM
but isn't a zr2 a s10 with the smaller 10 bolt

03-13-2006, 04:17 AM
I am putting full size axles front and rear in the ZR2. Gonna be pretty big, I mounted the rear tires yesterday, and the top of the box comes to the bridge of my nose (i'm 6'3"). Trying to get er don by May long.

03-13-2006, 07:46 AM
but isn't a zr2 a s10 with the smaller 10 bolt

ZR2 uses the 8.5" rear....most S10s use the weenie 7.5/7.625" 10-bolt as you're thinking. ;)


I'm curious... how close in width is the ZR2 axle to a fullsize? Seems to me they'd be almost the same.

03-13-2006, 06:06 PM
The ZR2 axle is 3.9' wider than a regular s10. Just as an example of the differance, the full size front diff whell mounting surface is even with the edge of my fender flares. I would say there is still a few inches differance between ZR2 and fullsize.

03-13-2006, 06:15 PM
I just figured it out by shaft length. Looks like about 1" difference [15]

ZR2 = 31"
fullsize 10-bolt = 31.5"

I think its so close because the 4x4 S10s use a wheel with ~5" backspacing on a 7" wide wheel. A front 10-bolt is couple inches wider than the rear... so what you're saying makes sense.

03-13-2006, 07:08 PM
A little off topic but would anyone know the common spline count on front and rear 10 bolts in an '88 Suburban 1/2ton?

03-13-2006, 07:59 PM
'88 is the changeover year for 10-bolt rear axle splines. Could be 28 or 30.

Front is 28 spline. (fronts didn't go to 30 until mid-89)