rear axel comparison

heres a few pics of all the different size rear axels together.
from left to right its a d60, 8.8, d44, d35.
notice that there's not to much of a difference in size from the 8.8 and d60.

Joe is that a 31 or 35 spline D60 shaft? I agree the 8.8 is plenty strong for most people, esp with the thick axle tubes. When your tubes flex it's game over.

BillVIsta did a comparason: STRENGTH COMPARISON OF COMMON O.E. AUTOMOTIVE & RACING SPLINES and used a 12 bolt Chevy as a reference.

GM 12 Bolt Diameter 1.2917 0.0%

28 spline Older Jeep/Dana 1.1960 -21.9%
30 spline Dana 44 1.2793 -3.0%
35 spline Dana 60 1.4876 57.0%

28 spline Ford 9", & Ford 8.8" 1.2083 -19.3%
31 spline Ford 9" 1.3333 10.7%
33 spline Ford 9" 1.4167 34.4%
35 Mark Williams 35 Spline 1.5000 61.2%
40 MW 9" & 40 spline D60 1.7083 143.2%

So what this is saying is:
The 35 spline D60 is 57% stronger than the 12 bolt
The 8.8 is 19.3% weaker than the 12 bolt similar to the 28 spline jeep.
the 30 spline D44 is 3% weaker than the 12 bolt
the 28 spline jeep is 21.9% weaker than the 12 bolt

its a 30 spline dana 60. Are they normally supposed to be 35 or something.

okay it looks like dana made two sets of rear d60 shafts, a 1.3 (30 spline)shaft and a 1.5 (35 spline) shaft. Looks like i got the shaft and got the smaller one. I guess i'll just have to upgrade them when I finally go with the new gears down the road.

When I switch my D44's from 30 to 33 spline they actual shaft diameter changed significantly. The 33 splines had the additional splines, but they were also negatively cut into the shaft diamerter whereas the previous shafts had splines extending outside the diamerter of the axle shaft... lots more beef.

Same time I have been running the D44's with 36.5 irocs on them in competition and on the trail without any issues... Blew up the factory locker and so upgraded the rear shafts along with it but the shafts have been pretty bomb proof.

md4wheelin wrote:

okay it looks like dana made two sets of rear d60 shafts, a 1.3 (30 spline)shaft and a 1.5 (35 spline) shaft. Looks like i got the shaft and got the smaller one. I guess i'll just have to upgrade them when I finally go with the new gears down the road.

Yeah, I looked at upgrading the rear D60 in my garage to 35 spline before I bought the built set of axles. It would require reaming to accept the larger diameter shaft. there are a few write ups on pirate on the reaming and covers the expensive tool and the cheapo home made tool for doing the job. After reaming it would require a new locker/carrier. paying someone to do the reaming can be $$$. So for now it has the 31 spline shafts in there. The built ones I bought have the 35 spline shafts.

mine are 35 spline, and i got lucky with aoi boring my splindles since they bought the tool to do mine, it cost alot more money now because of the time it takes to bore through them, if i had to do it over i would buy a 14bolt and shave the hell out of it and prob still spend less than i would with a 35 spline 60.


here is the only comparison of a stock 30 spline next to a 35

hey grason do you still have your 30 spline shafts by chance?

i gave em to dad for spares, i forget if they are the same lenght or no, if so ill give ya one.

sweet, i just talked to my dad and he said he has the equipment down at his works machine shop to ream out the axel so i'm good to go when I finally get around to uprading the rear axle.

If you have 30 spline Dana 60 , that is a stock axle . When I built my 60's I did the whole subang and did 35 spline inner and outter , as well as 35 spline in the rear , they are built kinda heavy but I didnt want to take a chance .
Most 60's were 30 spline from the factory , the Dana 60HD and 70 is where you get the 35 spline axles from .