Axle swap considerations

[archie73]

So you’re thinking you want to upgrade your axles, but which ones to grab at the junkyard-

FRONT
Fj60- 60”, stronger steering/knuckle interface
FJ80- 63”, stronger Birfield & knuckle, weaker front differential, steering solution are limited/expensive
Pre ‘04 Dana 60- variable width, stronger than LC oem, heavy
Post ‘05 Dana 60- 72”, strong aftermarket, tight turning radius, expensive/problematic steering solutions.

REAR
FJ60- 60”, drum brakes
FJ80- 63”, stronger pinion, 91-3 drum brakes/semifloat, 94-97 disc/full float
9”- ?????
Pre ‘99 Dana 60- Varying width & brakes, semi & full floats
Post ‘05 Sterling 10.5- 72”, full float
14 bolts- full and semi floats avail, many widths, drum until 99(?), huge axle shafts

1. I’m perfectly willing to edit these details, but it’s what I understand to be true.
2. I know there are others, but I’m trying to stick to the commonly available units out there.
3. I’m purposely excluding custom axles. I just feel like that’s a separate discussion

 

[archie73]

The reason I started this thread: I feel like it comes up in recent discussions regularly, so maybe this can consolidate the consensus. I’m also contemplating a build that I want more than the stock axles, so it’s timely for me.

From my perspective, I want:

• ~63” width
• 4 wheel disc
• ability to go to 40” tires
• To be able to not worry about hard lines.

I personally waiver in between FJ80 ff rear/widened FJ60 front and narrowing 05 SD axles. Both are time and cost expensive. Seems like the LC option is the easiest to package (links for this build). The tons will have tighter steering, aftermarket support and BEEF. Beef comes at the price of weight and packaging on an old frame (FJ4x). Also, I’m a believer in buy once, cry once.

 

[archie73]

Saved

 

[Mike Shull]

Is this thread for Paul? You beat me to it.

 

[Mike Shull]

Are you looking to upgrade, Archie? If so, are you keeping your Cruiser as is or are you going full crawler?

 

[matzell]

Let us know what you plan to do with this vehicle....
highway driving
dedicated trail rig, towed to events.
overlander wheeler
little bit of both?

I have vehicles with multiple axle variations.

What engine and HP numbers are you pushing
Auto tranny
doublers, low gears

All these play into effect. Driveline will be effected.
Tires size up to 40's will determine axle ratio needed
Driveshaft ends? flanges, open yokes


Need more details, but up to 40's I would go one tons.

 

[archie73]

Is this thread for Paul? You beat me to it.

Pauls questions echoed my current thoughts, so I figured I wasn’t the only person wrestling.

Are you looking to upgrade, Archie? If so, are you keeping your Cruiser as is or are you going full crawler?

My 40 is not slated for any major upgrades, just keeping it going seems to be hard enough lately. Currently I’m still mopping up my own sloppiness.

 

[archie73]

Let us know what you plan to do with this vehicle....
highway driving
dedicated trail rig, towed to events.
overlander wheeler
little bit of both?

I have vehicles with multiple axle variations.

What engine and HP numbers are you pushing
Auto tranny
doublers, low gears

All these play into effect. Driveline will be effected.
Tires size up to 40's will determine axle ratio needed
Driveshaft ends? flanges, open yokes


Need more details, but up to 40's I would go one tons.

My hope for this thread is more general, but I understand the need for more information so…

My desire for the next build is 60/40% highway/trail. I want something I can cruise 65mph without a death grip on the wheel, something I can let my wife or kid drive. I also have an affinity for dessert trips, so I try and get down there a couple times a year. Local trails are not quite to that intensity, but they have some flavor. So basically a highway crawler.

Power plant will seem plain Jane: LS auto. Transfer case will be determined by axles. LC axles; I have a splitcase that will get the 4:1 gears. SD sticks get something with a centered output.

Fabrication- I’m no pro, but I make things stick together. It won’t be ground breaking, but the formulas seem to be on the net and I can follow directions pretty well.

 

[GLTHFJ60]

To be able to not worry about hard lines.

With 40" tires, this is one ton territory for sure. Even chromo Toyota axles will pop if you have good reduction or have some power (or both)

As for which type, depends on the transfer case. If you're sticking with Toyota, you need a passenger drop front axle, which rules out superduty stuff. Kingpin Dana 60 in the front if you can find one, then a 14 bolt in the rear. Find an old cucv truck (roller) for cheap (less than 3k) and just slap those axles in your cruiser.

 

[EWheeler]

After watching @Broski and his 80 series on 39’s wheel in person, I believe a built 80 front axle is sufficient for most wheeling in the West, if you are linked & locked. Being linked (if designed properly) keeps shock loading the gears minimized, as long as you dont drive like a drunk 16 year old offroad. He wheels the s*it out of his rig, and isnt afraid to wind that thing up and giver the beans. I think he has gone through 1 ring and pinion, but he wheels a lot.

IMO, 80 series axles are the easy answer for most 40/60 series upgrades looking to stay full body and not go full on rock crawler/bouncer, adding width and a full floating rear axle.

The HP 8” has been argued by many to be comparable in strength to the LP 9.5” diff in the front, as the 9.5” is on the coast side of the gears when ran in the front.

 

[Mike Shull]

My hope for this thread is more general, but I understand the need for more information so…

My desire for the next build is 60/40 highway/trail. I want something I can cruise 65mph without a death grip on the wheel, something I can let my wife or kid drive. I also have an affinity for dessert trips, so I try and get down there a couple times a year. Local trails are not quite to that intensity, but they have some flavor. So basically a highway crawler.

Power plant will seem plain Jane: LS auto. Transfer case will be determined by axles. LC axles; I have a splitcase that will get the 4:1 gears. SD sticks get something with a centered output.

Fabrication- I’m no pro, but I make things stick together. It won’t be ground breaking, but the formulas seem to be on the net and I can follow directions pretty well.

I can go 75 mph at 2500 rpms without a worry. I have no idea what exactly enabled me to do that but it feels like a newer truck going down the highway and I bet that the extra length and width really help. I also bet that the solid and reinforced frame also help make for a stable platform for the highway, and perhaps the 1-ton gear. It’s heavy and it sticks to the road.

The problem that I will tackle next is that the LS produces a ton of heat under the hood, which is mostly only a problem for me on the highway after 2-3 hours of driving in the summer, which this year was March - October, ha. Even with double the recommended layers of lizard skin heat and sound protection, the floor and firewall reach temperatures in excess of 160 degrees F when the engine is around 200-205. I will be adding some stick on heat shields to the underside and sound protection to the inside of the Cruiser this spring.

 

[matzell]

When you say desert wheeling, does that mean go fast? IF so then fabricated Toyota Axle or tons should hold up, you may end up bending a factory Toyota housing unless you gusset it really well.

I always like to pick tire size and build around them.

Dana 60 HP Super Kingpin Front Axle - 40 Spline

The ECGS Dana 60 High Pinion Front Axle features the highest quality parts available on the market. Using the bulletproof Dana 60 High Pinion center section we build the housing to your specifications

eastcoastgearsupply.com

Chase and crew can build you whatever you need.

 

[archie73]

IMO, 80 series axles are the easy answer for most 40/60 series upgrades looking to stay full body and not go full on rock crawler/bouncer, adding width and a full floating rear axle.

The HP 8” has been argued by many to be comparable in strength to the LP 9.5” diff in the front, as the 9.5” is on the coast side of the gears when ran in the front.

So the main advantage of staying Toyota, in my mind atleast, is the packaging. They don’t have the massive pumpkins that want to hit everything. The relatively tight frames of the 4x series are a bit restrictive for packaging. They therefore lend themselves to a lower COG. For me in particular, this also has the advantage of spare parts. I have an 3 extra 9.5 dropouts & a split case to start the project out. “Which is Nice.”

While these are a nice starting point, I also want to mindful of the buy once, cry once idea. Which leads one to tons and the 05 & up SD axles seem like a good buy. They seem to be aging out and are coming down in price. There is a strong aftermarket. Main downfall I see to the them is the packaging and the cost of steering. Obviously, the packaging has a solution, people put these axles under everything. The steering I see two ways to solve: Weld on or Machined high steer. Since this is going to be a street driven I would want the machined knuckle/arm variety.

When I pencil out the cost of building the axles, forgetting the spare parts I have, the difference isn’t that far apart.
So for me in particular, it comes to beef vs packaging.

 

[archie73]

I can go 75 mph at 2500 rpms without a worry. I have no idea what exactly enabled me to do that but it feels like a newer truck going down the highway and I bet that the extra length and width really help. I also bet that the solid and reinforced frame also help make for a stable platform for the highway, and perhaps the 1-ton gear. It’s heavy and it sticks to the road.

This a good point about the heavier axles lower the COG, but it also brings the point of heavier rigs break more stuff in general. While I like the idea of a lightweight rig, mine will be more or less full body. I would love to end up south of 4K, but my 40 is 4.5k. Since the build will be longer and wider, it’ll likely be around the 40 weight wise.

 

[archie73]

When you say desert wheeling, does that mean go fast? IF so then fabricated Toyota Axle or tons should hold up, you may end up bending a factory Toyota housing unless you gusset it really well.

More crawl then high speed. This is one of the limitations of the my 40 that I want to over come, it’s not fun at speed on rough roads. I don’t have a strong desire to go fast in these situations, but it be nice to have the ability.

The fully fabricated axles look great, but the cost is prohibitive for a ground up build. For the purposes of this conversation I’d like to stick something that can be extracted to from an oem vehicle.

 

[Broski]

To be clear, my front axle has held up very well, I did damage a ring and pinyon dragging a 8000# 80 a cross the Rubicon trail but held enough to get me off the trail.
I also snapped a set of RCV inner axle shaft after 8 years of hard use. they were the older 28 spline ones.

My axle does have a full truss, knuckle braces, ARP hardware everywhere and RCV axles and all the other goodies.

My tire size is 39x12.50x17 so smaller then a 40x13.50x17

I do wheel it hard and IMO it has held up well and is up to the task.

 

[archie73]

To be clear, my front axle has held up very well, I did damage a ring and pinyon dragging a 8000# 80 a cross the Rubicon trail but held enough to get me off the trail.
I also snapped a set of RCV inner axle shaft after 8 years of hard use. they were the older 28 spline ones.

My axle does have a full truss, knuckle braces, ARP hardware everywhere and RCV axles and all the other goodies.

Your testament to the 80 running gear, and the packaging, are what give me pause to going tons. The next build should be lighter then an 80, I hope.

Can you elaborate on your front axle mods. This would be helpful to anyone looking to go this route? How do you address high steer? Or maybe you don’t?

 

[AgentOrange]

So I have a RuffStuff 9 1/2 up front and RCVs in it on 40s and it gets wheeled pretty decently. The Toyota 9.5 stuff is plenty strong as long as I'm not bouncing. That said, if I could start over, I would build 609s front and rear just for peace of mind. But I don't think I'll change anything on this rig and this set up has done Rubicon a bunch and Fordyce a few times and is hitting Johnson Valley next month and I'm not worried. Even dead drug a Sequoia out of Rubicon this year.

 

[Broski]

Your testament to the 80 running gear, and the packaging, are what give me pause to going tons. The next build should be lighter then an 80, I hope.

Can you elaborate on your front axle mods. This would be helpful to anyone looking to go this route? How do you address high steer? Or maybe you don’t?

I'm running the stock set up with the steering behind the axle. I really like this setup as it protects the tie rod and hydro ram.
As far as mods 5-29s with OEM E-locker, full Truss from spring perch to spring perch, knuckle gussets top & bottom, bash plate front & bottom, All ARP hardware and RCV Ultimate axles.

If I were to go high steer I would use the Front Range High steer Knuckle kit with there keyed steering arms. Steering arms are keyed to the knuckle. SWEET
FJ80 High Steer Knuckle Kit - https://frontrangeoffroadfab.com/fj80-high-steer-knuckle-kit/

 

[Mike Shull]

I'm running the stock set up with the steering behind the axle. I really like this setup as it protects the tie rod and hydro ram.
As far as mods 5-29s with OEM E-locker, full Truss from spring perch to spring perch, knuckle gussets top & bottom, bash plate front & bottom, All ARP hardware and RCV Ultimate axles.
View attachment 4021511
If I were to go high steer I would use the Front Range High steer Knuckle kit with there keyed steering arms. Steering arms are keyed to the knuckle. SWEET
FJ80 High Steer Knuckle Kit - https://frontrangeoffroadfab.com/fj80-high-steer-knuckle-kit/

I had no idea that you had all of that underneath your 80. I need to take a closer look for the next time that I see you.