corax

whenever you upgrade one part, expect another to become the weak link. last month, after less than a year behind the 300hp 1UZ VVTi, the 8" e-locker rear finally gave up the ghost, so a new rear axle seemed appropriate. I ran some numbers, and for a little bit more than what it would cost me to build a stout 8.4" Toyota axle, I could build a bullet proof Ford 9". This axle hasn't been used for nearly 30 years, but aftermarket parts are cheap and plentiful plus it's strength is well known and it's still used in motorsports. A good comparison of the D60 and Ford 9" can be found here:

https://www.tacomaworld.com/threads/...#post-17132583



This is what I started with - the axle ends made me think it was a 31 spine (it wasn't) and I was hopeful it might have a TracLok LSD as those were a very common option (it didn't), but it does have "early" big bearing ends. Funniest part about the axle I bought, it had 2.75:1 gears in it




after stripping off all the bracketry. this housing measured 60.5" flange-to-flange, add 5 inches for the axle to poke out, and it's almost a perfect match width for the front long travel



a simple back brace brace was installed and 95-00 Ford Explorer disc brakes were mocked up. I like the Ruff Stuff F9 back brace better, but was hopeful that this style would leave me with enough room to keep my 33" spare underneath the truck (it didn't). The back brace was carefully welded using (77) 1" back stitch welds to try to reduce warpage (I still got 0.5 degree toe-out afterwards, but was able to reduce that by heat shrinking the front of the housing). The Ford disc conversion is a direct bolt-on for "Torino" style or "late" big bearing housings, but can work as well on "early" big bearing housings with a small amount of bolt hole slotting. A special spacer also has to be used between the bearing retainer plate and the bearing if you decide to go with Exploder discs (Currie makes one, so does Dutchman Axle and several other companies).



getting the spring perches tacked in place so the pinion flange angle matches the transfer case flange angle. Of note is that the top of the axle tube on all Ford 9" housings is crushed flat at the factory, so normal spring perches for round tube need some grinding to have a nice tight fit before welding. I also welded in a 3/4" NPT fill/inspection port at the top and 3/8" drain plug at the bottom rear of the housing (there was no drain plug originally)



Some other goodies arrives from Dutchman Axle in Idaho. When I priced all the parts I wanted, I realized that they could build the center section for about the same cost as the individual parts. the build list is something like this: Strange Engineering nodular Pro Series center, cast iron "Daytona" style pinion support, 4.86:1 US gears (close enough match to the 4.88:1 I have in front), and Detroit Truetrac helical LSD for 35 spline axles (largest factory F9 axle shaft is 31 spline, 35 spline also requires a larger differential side bearing than Ford offered, so more beef). I also used a Trail Gear F9 triple drilled pinion flange so a Toyota driveshaft could be bolted on (this one seeps a bit, I think it might have to do with the machine finish at the seal area and might try polishing it, Nitro Gear also has a triple drilled F9 pinion flange)



35 spline axles are beefy. Dutchman made them in 6 x 5.5 bolt pattern for me with a center pilot to match the Exploder discs. I had them ship the axles without bearings and lug studs installed so that I could use the axle flange as a pattern to drill the Exploder discs to 6 lug as well. Axle shafts are using the stronger Set20 tapered bearings which are normally lubricated by the gear oil in the housing (need to remove the inner axle seal), but sometimes leak if you have to remove and reinstall the axle shaft. Dutchman also offers an optional bearing retainer collar which lets you keep the inner axle seal, for less chance of a gear oil leak, which means the tapered bearing has to be packed with grease so it doesn't die a quick death. If I had to do it over, the only change I would ask is that the center pilot on the wheel flange be extended a bit so I could run a hub-centric ring for the wheels (a dab of crazy glue would work to hold it in place). If you order axles to work with Exploder brakes, make sure they have 2.5" backspacing from the wheel flange to bearing (many stock axles have 2.375" and the rotor contacts the backing plate) and there needs to be an inspection hole drilled in the wheel flange to be able to tighten the bearing retaining plate nuts.



I weighed everything before assembly and this is what I came up with:

48.1 lbs for both 35 spline axle shafts - fully assembled

39.6 lbs for both rear disc assemblies - backing plates, calipers, parking shoes, disc pads

62.0 lbs for housing with all brackets/mounts installed

77.9 lbs for fully assembled Strange center section

227.6 lbs total dry weight without the 3.5 qts of 85-140 gear oil it takes to fill it


shock mounts were located and welded in place to let me use 10" stroke Bilstein monotubes with the stock upper mounts - a future project is going longer stroke with outboard shocks, but I needed to get this back on the road





I might try shifting my auxiliary gas tank and spare tire hoist back a bit to see if I can put the spare underneath again, but this is too close at ride height



plenty of room for the brakes inside stock 15" Taco alloy wheels. Brake feel is great and stopping is much better than my old Toyota drums ever were.



just a a couple inches of poke on the rear axle, but track width now matches the front.

bone collector

Great write up and great work!

rattlewagon

Thats killer!! 9s are great axles.