DIWhy Heavy Duty Driveshaft

I created my own driveshaft for off road use and wanted to document it in case anyone else wants to attempt it. I got the idea from Wide Open Design but wanted something a bit cheaper. Since I had an extra driveshaft to cut up, I'm only ~$150 into this.

https://www.wideopendesign.com/1350-driveshaft-kit

The idea is to leave the carrier bearing/front half of driveshaft on the truck and only swap the rear portion. Undo four bolts at the rear axle and slide the driveshaft out of the slip yoke.

If you want to cut up an existing driveshaft, you'll need the following:

• Spicer 2-28-2777
  
• 3' of 2" x .120 DOM tube
• 3" of 1.75" x 0.313" DOM
• 1330 U joint (or reuse existing one)

If you want to create it from scratch, you'll need the following:

• Spicer 2-28-2777
• 3' of 2" x .120 DOM tube
• 1330 U Joint
• Spicer 2-40-01930 (currently backordered)
  
• Powertrain Industries 3302-185 (currently backordered)

First, I drilled three holes into the 3" section of DOM so I could add some plug welds, then welded it all together. Then did the same to the 3' section of DOM.







I then laid the two driveshafts side by side and cut the tube to length. I don't want to give a measurement in case yours is a little different than mine, but I cut about 6" off.

Once it was cut, I inserted the U joint weld yoke into the other end. It's very important that the U joints on either end line up, otherwise you'll have vibrations and binding offroad. I used my digital angle finder to ensure everything matched up. This is also a good moment to point out that the splines on the slip shaft will only go into the slip yoke one way, so there's no guesswork if it's correct when installing it.

Getting the weld yoke into the DOM was a bitch, it's truly a press fit as I was unable to hammer it in. I ended up having to grind out a little bit of the DOM and a little bit of the weld yoke, then was able to hammer it in.








And that's it! Then just paint and reassemble everything. Its maiden voyage is this weekend so I will report back on strength and drivability without it being balanced.









The DIWhy driveshaft ended up being 3/4 pounds lighter than the factory driveshaft as well.

 

What's the difference in diameter and wall thickness between the WOD and OEM and the WOD? Looks like the WOD is 2.5" x 2.50". Definitely seems like it would take a lot fewer impacts.

 

OEM - 3.5" x 0.065"
WOD - 2.5" x 0.25"
DIY - 2" x 0.120"

The WOD is without a doubt the strongest one of the bunch but I felt it was unnecessarily overkill, plus more than I wanted to spend. I'd need their kit, plus the tube, plus some 1350 -> 1350 U joints. It would cost closer to $600. Of course I could source the Dana parts myself since all they're doing is reselling, but I didn't pursue that avenue so I'm unsure how much money I'd save doing that.

My train of thought is that if .120 wall DOM is strong enough for rock sliders, it's strong enough for some gentle impacts on a driveshaft.

 

Awesome write up, thanks.

 

I should have re-read that and posted after having some caffeine. An extra half-inch of clearance (or more, since the shaft is at an angle) over the WOD should be nice, too.

 

I'm very curious to see how it does this weekend. It's my go-to spot so I've run it a dozen times which is great for comparing differences in the truck each time. Big differences for this trip is the driveshaft and the rear hanger/bumper setup.

 

God those wing welds look horrendous in that pic. I promise they're not straight boogers.

 

Great write-up. I also have a junk spare driveshaft and was thinking of doing the same thing. I would definitely be trying to get mine balanced as mine's not a trailered rig.

Sub'd to see how it goes..

 

I think once the other Spicer part becomes available early next year, it will really be the key to making a driveshaft both street friendly and stronger. I say this because then both ends would be a press fit into the tube and it would be incredibly straight and easy to be balanced.

 

Looks like I'll be waiting.

Keep that shaft spinning as slow as possible. Might have some vibes. But can't be worse than a bent driveshaft.

 

I was amazed at how snugly all the tubes nestled together at the slip yoke side. Measured with my calipers, they're all within .001" of one another so they slid together with surprisingly minimal play. I guess it will be fine up to ~40-50 mph but we'll see, tomorrow will be the test. The truck is currently trapped in the garage by my trailer.

 

One thing I'm unsure of and don't even know how to begin to calculate is the critical speed of the smaller diameter tube. Even though this one is double the wall thickness, the larger diameter tube will withstand certain forces better. So all that to say, proceed with caution if you plan on driving with one of these on the highway. My gut tells me it would be just fine but math may say otherwise.

https://4xshaft.com/blogs/other-vehicle-drive-shaft-tech-articles/toyota-tacoma-drive-shaft-tech

 

Hmmmmm. Think I might try this with my factory shaft down the road

 

Just a heads up for any one that regularly goes to the junk yard. That same style slip yoke came in the older Grand Cherokee ZJ and possibly the WJ. Very similar slip yoke with the same thick splines. You'll be able to take the front and rear shafts and slips. We would run these on our XJs.

 

So besides sounding like a civic how did the driveshaft hold up? How fast did you go? Vibes?

 

It did great! Went as high as 40 mph and no new vibes that I noticed. I had it up against a rock pretty good and did take some paint off but no dents. So far so good.

 

Very cool option... I'm on my third driveshaft, so this might be the ticket to saving future issues.