Drop spindle Dana 60 build

[Qumanchew]

I thought some of you might get a kick out of this pile of parts I cobbled together. I'm calling it a " drop spindle 60" because my original design was using spindles instead of unit bearings, but also because I don't know what else to call it.

So a little back story/ motivation for building this. This Bronco is my wife's, so first and foremost it's a driver, so that is what it has to do best. It only has 32s, and isn't getting anything bigger. It's honestly the best handling early bronco we've had...buuut, I've been getting the itch to wheel it more, and obviously the diff clearance on 32s is not much fun. I've been building this in my head for a while. I decide it would be a good winter time project and started putting this together last November. The wheel centerline is 3.5" below the pumpkin centerline giving it that much more diff clearance.

I have no idea in the long run if this is going to be a win or fail, but it's been a fun project regardless.

 

[phred]

That looks a little like the axle Todd Foss built for his truck although his is only “kinked” on the long side if I recall correctly. More details please I very intrigued on how this is put together.

 

[Yeller]

Been a few done. The ones I’ve been around in the rest had a hard time surviving due to the weird torque loads on the housing. With modest tire size and not trying to hang with comp buggies I think it will be great or at least a great experiment. I like things tried that are different, so I’m watching.

 

[DirtDonk]

Interested to see more details as well

 

[JB Fab]

Build thread?

 

[Qumanchew]

Been a few done. The ones I’ve been around in the rest had a hard time surviving due to the weird torque loads on the housing. With modest tire size and not trying to hang with comp buggies I think it will be great or at least a great experiment. I like things tried that are different, so I’m watching.

We're on the same page. I'm definitely low on HP and minimal gear reduction with a np205 and 3.50 gears.

 

[Qumanchew]

Build thread?

In the works. I've been working overtime so classic bronco time has been minimal

 

[Qumanchew]

I'll start at the diff and work out. I shaved the housing and added a fill plug to the top as well as a breather and fitting for an arb. I scored the arb on eBay as an open box for $900. It's a 35 splined unit. I'm using the seals-it axle seals just outside of the bearings. Coming out of that are short side, 35 splined Dana 60 front shafts. I made some aluminum spacers to hold the shaft centered in the tube. Basically, two half moon shaped pucks that went around the shaft before it was slid into the tube.

 

[Qumanchew]

One big goal from the beginning was to use all off the shelf parts for the wear/ breakable parts and I was able to accomplish that.

Attached to the inner axle shaft is a 1480 series driveshaft yoke to a 1.5'' splined shaft with a carrier bearing, to a 1480 series slip yoke. The carrier bearing on the splined shaft is what would be on a truck with a 2 piece driveshaft. I had to make the pillow block to hold that bearing. I'm calling these parts the intermediate shaft, basically just a short driveshaft.

I debated a long time on how much drop to build in and u-joint angle was a big concern. I settled on 3.5". That equated to 21 degrees of angle at the joints. There wasn't any science involved in that decision, it just seemed exceptable.

 

[abrogate932]

Anyone else remember Atomic Axles?! I just had a flashback

https://www.pirate4x4.com/threads/atomic-axles-feedback-wanted.859936/

 

[Qumanchew]

Very interesting. I might have under built mine, I see in the link that they're shafts are good for 1000hp, haha! I'm assuming they are not around anymore.

 

[Qumanchew]

Attached to the intermediate shaft is a Dodge Dana 60 stub shaft that goes into a Dodge 1500 unit bearing with the 5 on 5.5" lug pattern. I was really surprised when I realized that the 60 shaft has the same splined count and diameter as the 44. That being said, they're not the same shaft, the 60 shaft has the 55x u joint, which is the same as the 1480, except for the caps. Speaking of that, for each side I just had to buy one 1480 and one 55x, take two of the caps from one and swap with the other, creating a 55x/1480 joint.

Running that shaft in the 1500 unit bearing did create a problem though. The hole where the unit bearing sits in the knuckle isn't big enough for the bigger joint to fit through. What I ended up doing was was making an adapter player that bolted to the unit bearing and then to the housing.

 

[Qumanchew]

I wanted to keep the bronco at it's current ride height , which is 3" over stock. When I lifted it I moved the axle back like everybody else to center it better in the wheelwell. With the pumpkin being raised up it put it 0.5" higher than the original 9". With the size of the Dana 60, this was going to be a problem at full stuff, the diff cover was going to hit the cross member. The solution I came up with worked out really good, but was a major pain in the ass. Instead of having the drop go straight down it also is rotated back 1". I spent a lot of time getting everything true. I started by setting the pumpkin up at the desired pinion angle , welded that solid to the beam and went from there.

 

[Qumanchew]

Some more pics to this point.

 

[abrogate932]

Very interesting. I might have under built mine, I see in the link that their shafts are good for 1000hp, haha! I'm assuming they are not around anymore.

I’m not sure what happened to Atomic Axles, but that thread is 15 years old and I haven’t seen one since.