Actual Moderator with a Tacoma...But Definitely Not a Build Thread

And because everyone always seems to want to tell me how I should build my rig. Here is why I went with a 9" over a Dana 60.

First off...we're not comparing junkyard housings here. Sourcing a junkyard housing is really starting to dry up and it would be like comparing apples to oranges in that situation. We're comparing aftermarket fabricated housings. The reality is the sky is the limit when it comes to fabricated housings for both the D60 and 9". Secondly, we're also talking about semi-float housings. Going full float has advantages in terms of strength and trail repairs, but you will also lose the tone rings on the axles. Which means you can toss out any of the electronic nannies you may or may not love including ABS, VSC, DAC (4runners/Fjs), a-trac, traction control and crawl control. In addition you can expect at least another 1500-3000 bucks in cost depending on what kind of hubs you decide on. I'm perfectly content keeping semi-float and not having my dash look like a Christmas tree.

Now...onto the real meat. First off, buying an axle isn't just a matter of what's the strongest axle. I'll fully agree that the D60 is slightly "stronger" in terms of pure ring gear diameter. Yes, the ring gear on the 9" is smaller than the 60 (which is 9.75"). But a whole lot more goes into buying an axle aside from just gear size. Usage, application, ground clearance, weight tire size should all be take into account.

Pinion
Take a look at the below image that compares pinions of various Dana pinion gears vs the 9".





Pictures speak 1000 words, but notice the relative size of the 9" over the D60, but more importantly, focus on the tooth pattern (lime green line). 9" teeth are significantly larger in thickness and the teeth themselves visually have a spiral pattern gear and angled more. With a 9" you have almost double the amount of teeth in contact at any given time. And as gear ratios go increase in size (numerically), the 9" tooth contact increases because of the change in tooth pitch. Anyone who's sheered one or more Toyota R&P gears would appreciate the fact that the larger you go in gear size, the more tooth contact, the stronger the pinion tooth strength. The downside is the 9" gears are less efficient (due to increased surface area friction) than the D60. Ford also uses 3 pinion support bearings rather than 2 that you see on most axles. A 9" has an additional pocket bearing that has a retainer built into the case (back end of the pinion..see red arrow above and second picture). This supports the pinion's head and combats gear deflection. Some will argue that this 3rd bearing was a band aid that Ford did because the normal two pinion bearings are close together which results in larger leverage stress. Thus in the 60s, Ford introduced a Daytona pinion bearing support which houses larger bearings. So yes, it's still build with 3 bearings instead of 2 and still being used over 70 years later...so the argument is moot other than the 9" has one more bearing to replace or potentially to go bad.

Ring gear
As previously stated, the ring gear diameter on the Ford is appropriately named being 9 inches while the D60 is 9.75 inches. That's it right? Nope! Again, see image below.





The scale shown on the first picture is is actually comparing the D70, but you can see the 60 beside it. If you measure heel to toe thickness of the gear itself, the Ford 9" has the thickest gear out of all of them at 1.655". Yes the Dana gears have a larger outside diameter, but it's not the "heal to toe" thickest gear. Another measurement to keep in mind is what's called hypoid distance (or gear offset) as shown in the second picture. Hypoid distance is the distance from the center of the pinion gear to the center of the ring gear. If you compare roughly equal ring and pinon diameters, the higher this distance is, the higher the inherent strength of the R&P. When the gears have a larger offset, you have more teeth in contact (as mentioned above in the pinion gear section above). D60 has a hypoid distance of 1.062" compared to the 9" which is 2.25".

Ground Clearance
Remember that larger ring gear the D60 has? It doesn't come without a cost. I looked at a lot of housings over the years and the D60 will consistently be about 3/4" lower when compared to a 9". 3/4" may not seem like much, but that's the equivalent of moving tire sizes up from 33's to 35's.

Weight
Assuming like for like axle builds (same size axle tubes, bracing, width, spline count, etc.), a D60 will be around 30-40 pounds heavier of unsprung weight when compared to a 9". Those that are strictly rock crawlers typically won't care about this. Those that are setup to be desert trucks, weekend warriors, and DD's will care. Any pound saved (especially unsprung weight) is a plus.

Gear Ratios & Aftermarket
Gear ratios with the D60 are fairly standard like Toyota. However largely due to stock car racing, the 9" has almost limitless gear ratios. I doubt anyone on this forum will give a shit since you'd be restricted to matching (or nearly matching) the gear ratio on the front. However if you are a prerunner or SAS, your choices in gear ratios are broadened. And the pure quantity of aftermarket builder parts for the 9" are mind-numbing. This includes options for 9.5" and 10" ring gears (yes you read that right) which are available if the housing supports it or can be notched.

Third Member
The advantage of being able to remove a third member is really up to the owner. However the 9" has a drop out 3rd member like Toyota while the D60 does not. Again most people won't care one way or the other here, but I personally like the ability to remove the third member for gear work rather than removing the whole fucking housing or towing the truck somewhere. Being able to drop the 3rd and work on it on my bench or to drop it off at a gear shop is a hell of a lot simpler than doing gear work on the truck. In addition LubeLocker sells reusable seals for $20 so you never need to worry about RTV ever again.

TL;DR
I honestly do not care how you build your rig. Do what you want. I build my truck for my requirements and my needs. I'm not soliciting for advise.

 

Who said I'm not?

 

I already told him about it. They have a "note" in their system now. I believe largely due to you and Jonburtt both having more or less the same issue.

 

I don't think it was the runout specifically like yours. But something with the hub machining was off. Regardless I mentioned both issues to the guy and he already knew what I was asking about before I even finished.

 

Its their standard verbiage. They sell their axle as a builder kit designed to retain factory drums. Builder choice to use that or something else.

 

Nope. I would do a 60 before either of those. The carrier in the tundra diff is shit too. Deflects like crazy. And everything would have to be custom as their aftermarket support pales in comparison.