Cougarfreak

I have been running the stock Toyota 8" rearend in my 4Runner with 4.56 gears, and a Detroit Locker. Back in 2005, I was Chasing a VORRA desert race in Hawthorne for my friend Oscar Lara #724. We were prerunning the course with 5 guys total in the vehicle (includes me driving), and a full load of recovery gear in the back in case we were to get stuck, or broke. There is an 8 mile or so section on the course that has 6 30' rollers that one can hit as fast as your vehicle can go... we hit them at about 80mph. It was like a roller coaster ride... an absolute BLAST!!!!! At the end of the section, I stopped to make sure everything was ok.... well, it wasn't. I had installed airbumps in all 4 corners, but the rear housings I mistakenly only mounted 1/2 way up the frame. The housing bent into the center of the frame cocking the air bumps off their pads, and rendering them useless. I nursed it back to the pit area where I heated up the frame and moved the bump housings back to where they needed to be, then full frame gusseted both sides with some 0.250" angle iron. That did the trick and I was back in business. Unfortunately, Oscar's race didn't fare much better. Oscar's motor caught fire from all the ATF fluid that was puking out his breather tube (faulty valve body) and ended his race 3 miles from finishing in 1st for his class. The long term effects of this Roller coaster ride were bent axle tubes from the perches out. this issue didn't rear it's ugly head until last year (2006) when my wheel bearings started making a terrible grinding noise on the way home from a Rubicon play day. Time to ditch the 8"...


I thought about a Diamond Axle housing, or a race 9", but both would have set me back at least $3500. I weighted my options, and $$$, and... I sourced a Dana 60 rear axle from PnP out of a 1975 Ford F250 Hi-Boy.


The rear axle shafts were 16 splined (30 splined are much more desireable), but I was going to have to go with custom shafts anyway since I was cutting it down from 64"(stock width WMS-WMS) to 60.75" (Stock 3rd gen 4Runner 8" width). I didn't keep it stock width because I didn't want to have to run spacers in the front to keep the track width proper. The cost of having the axle tubes cut down and bored out to accept 35 splined axle shafts was not too bad, so I went that route. I could have gone with dually hubs (They make the WMS-WMS narrower, but I'm not sure by how much), but I didn't want to make another trip to the junk yard to get those. I also didn't want the hub sticking out too far, as I tend to smack them from time to time (found this out when I ran center cones in my rims and had to cut them out after deforming them on a wheeling trip). So here's the list:

* The diff cover is from Ruff Stuff and is 0.375" thick (that aughtta handle a good beating).
* Axles are 1541 Chromolly 35 splined Yukon trim to fit. They arrived 33.5" in length.
* Rotors are '75 Chevy 3/4 ton fronts (lots of years use same rotors)
* '76 Cadillac El Dorado brake calipers (parking brake)
* Great Lakes Offroad's mounting brackets (Ford and Dodge are different)
* Detroit Locker
* 4.56 Yukon Gearset

Time to install!!! I cut down the axle shafts. This is what they looked like out of the box:


Time to trim... Driver:


Passenger:


Trimmed an extra 0.120" each side and chamferred:



Looking good with 35's!!!


Set under the truck, 1.5deg angle pinion flange to the d-shaft to keep everything running without vibration:


Welded perches (I love using gas):


Time to Truss (No more bent housings for me!!!). 2"x4" 0.120 wall square tubing will be used. This will go on top of the axle. The axle tubes are beefy already with 0.50" wall, but I saw a Dodge in a desert race make a smiley face outta his front axle with the same tubes. If I bend this axle, there's going to be a lot more wrong with the rig than just bent axles!!! Let's not find out!!!!

Cougarfreak

Is "A" going to be better than "B"? Lighter, yes (I kinda threw lightweight rearend out the window when I decided to go with a D60), but will it justify the extra effort to get to "A"?

Stomis

Very nice! Although I would have gone with a toyota rear and gusseted it up and threw chromeoly shafts in. Clean install and super nice welds...

Cougarfreak

I thought about that, but would have cost me 3x as much to get to where I am now. Finding a straight housing is tough. I know Sky is retubing for a decent price, but the ring and pinion size and my vehicle's weight with the exo and all bombing through the desert had me thinking bigger rnp. I blew up 2 Genuine pinions last summer on mild trails with finesse driving, and vowed never to have that happen that easily again!!!! I appreciate your input tho

Stomis

Hmmm try getting ur R&P cryod

881stGenRunner

awesome install, i would rather have Gusset B. awesome install

Cougarfreak

heat welding area with propane torch, 1" welds per session, each session welding each corner alternating sides and ends, working from outside in. 30 min cool down between each session. tack 2" square tubing (cut off and ground after final cool) to the bottom side of the axle tubes...

Buck01

I really have no personal experience on this subject but will throw this in the mix. I saw on extreme 4x4 last week i think. They drilled the holes in the truss. The the added round tubing in the holes. They said it was for additional strength. Not sure how acurate that info is just thought I would share it.

Your work looks great.

dropzone

iTrader: (6)

I have never bent an axle, but if you plan on prerrunning with a similar weight again (maybe a 3 guys instread of 5 next time) go with truss "B"..

btw: nice welds....

Grizz1

I have a set of dana 60's in my Toy with a 4-link and coil overs that I use to play in the mud and trail ride with.

Cougarfreak

Thanks Dropzone... I've been practicin'

Now I just gotta clean the axle and weld it!!!

Cougarfreak

I've been informed that I will be lucky not to have a bent axle welding only to one side of the tube, and that I should consider a small truss on the bottom side of the axle as well to even out the heat and shrinkage to both sides. I'm trying to avoid a bent axle here. If I'm going to be lucky NOT to have a bent axle after welding in this truss as I have it, I'm a fool for putting it in as it sits in the first place. Luck and I rarely get togther at the same time. For rock crawling, I soooo don't need it. But that's only part of the vehicle's designed adventures. I also want to be able to fly in the desert and dunes, and for that, I'm thinking I do need it. i know I can't have my cake and eat it too, but I wanna come close!!! Build it for the worst conditions in any one particular adventure without severely detracting from any other adventure. that's my philosophy. Am I over thinking this? Probably, but I don't like doing things twice, and I don't want bent tubes again!!!!

etan

That's Huge!

Rock Slide

iTrader: (1)

Well, I def do not know as much as others may know about axles, but like Buck01, I too saw an episode of 4x4 that explained the whole truss idea for top and bottom.

Don't know if it'll help you from what you already know, but they said you would want to truss the top of the axle if you do a lot of rock crawling. (Helps keep the axle from bending into a "U" shape). Plus you gain clearance over the rocks while making the axle stronger.

However, for desert racing & pre-running, they suggested to truss under the axle. (So often the axles bounces while desert racing, it tends to cause the axle to bend in the shape of an upside down U.) Thus the need to truss underneath.

So I guess it comes down to what do you do more often...rock crawling or some type of desert racing (know you don't race, but you know what I mean). Or you could just truss both sides and forget about it

Good luck!

89silverpu

You could just put it under my truck and end your predicament! hahaha

Cougarfreak

hahahahaha smart assed kid!!!! I've a habit of overthinking things... This may be one of those times.

Cougarfreak

Possible solutions include... not trussing at all (get's me on the trail quicker, but worried), Trussing the back:


or the bottom:

Cougarfreak

I am having serious thoughts of ditching this whole idea of trussing the axles and just not jumping the rig. The axles are only one area the jumping abuse will effect. I'm not racing it, and I rock crawl more than I run the desert. The reality of NOT needing trusses for mild desert running/chasing/prerunning, and certainly not rock crawling is very real. In reality my rig is more set up for rock crawling anyway with only 2.5" of uptravel in the front end. sure I could go more, but then it would be taller and th CG would be higher... I'm thinking I'm trying to go to an extreme that just isn't realistic for this rig. I'll build a 700 truck and jump it if I really need to jump something... or just use my quad... I do appreciate everyone's input, and thank you very much. I haven't given up yet, but I am considering it.

toy power

No man! I can't believe you're even saying that. That rear end is awesome, and it looks like you have already done some excellent work with it. Since you already have the upper gusset made, I would go ahead and weld that on. That gusset is really strengthening movement either way, and I really think that the benefit of a lower gusset is not great enough to warrant building it and having less ground clearance, etc. Don't freak yourself out, man. You're almost done anyway. That axle is seriously tough just like it was when you dragged it from the junkyard. With the thickness of those axle tubes, you would really have to burn on it to warp it while welding that gusset. Bottom line is I don't see you have any worries here. Put it on and hit those rollers at 90mph.

Cougarfreak

hahahahaha Thanks for the booster!!!! I may just do it for the educative purposes. worst case scenario, I have to go spend another $150 on a new housing at PNP, and another $300 to cut it down and broach it again for the 35 splines.