3rd Gen Rear Axle Upgrade Options - Full Float Conversion vs Full Float Diamond

[JWaldz]

For the past month or so I've been collecting notes on parts to do the Full Float Conversion. I just got off the phone with Brian, onwer of FROR and got to talking about other options.

As you can see the kit itself costs $700. It comes with the adapters, a proprietary seal adapter and seal kit, Moser shafts, and some other odds and ends. You then have to piece together all the other parts from a early model live axle (solid front) pickup. This includes hubs, spindles, bearings, seals, flanges, rotors, calipers, and the various studs, nuts, and bolts, etc.. In total, if you go with higher performance parts that are 4130 or 4340 chromoly, you can spend upwards of $2,000. This doesn't include installation if you're not familiar with front solid axle pickups. Not saying I'm not, just saying it can add to the price. The only downside to the kit is that it has a lot tighter tolerances than a semi-float design. If the weak stock toyota axle housing is bent, it can cause failure. [MENTION=67615]Dirtco[/MENTION] and [MENTION=90485]URBAN ASSAULT[/MENTION] know about this with experience.

On to the 2nd option, which is what I was discussing with Brian is, I could skip the conversion all together, rid of the stock housing, and have him build me a custom Diamond Axle housing that associates an 8" elocker 3rd (which Is what we have) and all the stock axle 5-link geometry. I can have the axle built in a full float that associates the adapter to mount all the same pieces from an early model SFA pickup like I mentioned above. The only difference is about $1,000. The bare axle with the full float adapter, all the tabs for shocks, links, coils, etc would cost around $2100. This is an upfront cost. The rest are the pieces I can buy over a period of time. Again, depending if how high of performance parts I buy will determine how much I spend overall.

Both options lose ABS and the E-Brake



So to put it in sparks notes.

Option 1: Conversion on stock housing. Plenty strong provided housing is completely straight. No ABS, No E-Brake. ~$2,000 ($700 for conv kit payment up front, $900-$1300 for parts over time). 2-4 Week Lead Time

Option 2: Diamond Axle, stock geometry (bolt on). VERY Strong and same outer components as conversion kit. No ABS, No E-Brake. ($2100 for built axle and adapters payment up front, $900-$1300 for parts over time). 8 Week Lead Time

 

[cashmoney]

How many people have broken rear axles? I've yet to read of one. Not saying they don't just that it seems rare and doesn't seem worth the cost for something that pulls weekend crawler duty.

 

[Kryptoroxx]

What's your use of the truck? Don't use a butcher knife where a butter knife will do.

You can brace the stock axle too.

 

[pauldub]

I think Brian is working on an upgrade to the full floater conversion kit and it will use late model 4Runner rear disk brakes which include a drum e-brake. I don't see any reason that the axles couldn't be made to accept the ABS tone ring but I don't know if that is his plan. I'm considering a full floater just so I can unlock the hubs and tow the 4Runner.

 

[IBallEngineer]

So to put it in sparks notes.

Option 1: Conversion on stock housing. Plenty strong provided housing is completely straight. No ABS, No E-Brake. ~$2,000 ($700 for conv kit payment up front, $900-$1300 for parts over time). 2-4 Week Lead Time

Option 2: Diamond Axle, stock geometry (bolt on). VERY Strong and same outer components as conversion kit. No ABS, No E-Brake. ($2100 for built axle and adapters payment up front, $900-$1300 for parts over time). 8 Week Lead Time

All things being equal, I would love the Diamond Axle, you can get it up to 3" wider than stock, and it is proven great quality. When I first bought my 3rd Gen I had the dream of doing an SAS and using the Diamond Axles, including the full floater in the rear.

One added benefit to the full floater is you can use front hubs and flat tow with no driveline rotation at all. HUGE if you flat tow behind the RV, as I do.

If the money isn't a problem, go for it!

:whipping2

 

[JWaldz]

How many people have broken rear axles? I've yet to read of one. Not saying they don't just that it seems rare and doesn't seem worth the cost for something that pulls weekend crawler duty.

I doubt the general 3rd gen population will ever have a broken axle or even will ever break an axle shaft. Not including those in rear end collisions. However, I'm willing to bet that those that wheel harder than most can likely have a imperfect axle housing. Even after a days wheeling can cause the slightest runout. Given that that semi-float design has such leniency when it comes to tolerances you'll likely never know of even the slightest bend in the housing. You would in a shaft, but not the housing. The full float design is much tighter tolerances. The slightest bend in a housing and you'll start grenading parts in a domino effect. This worries me.

What's your use of the truck? Don't use a butcher knife where a butter knife will do.

You can brace the stock axle too.

Sure I can brace the axle, but it's like putting a band-aid on a bullet hole wound. It's only going to last so long. Not to mention that trussing a stock axle housing takes a lot of precision and know-how. Not just welding skills. The thin metal housing can certainly get warped if you're not careful. My truck as of now is a weekend warrior. That's soon to change as I'm taking a job with an offroad fab company and will be attending more events and trips throughout the year.

I think Brian is working on an upgrade to the full floater conversion kit and it will use late model 4Runner rear disk brakes which include a drum e-brake. I don't see any reason that the axles couldn't be made to accept the ABS tone ring but I don't know if that is his plan. I'm considering a full floater just so I can unlock the hubs and tow the 4Runner.

He is working on a new kit. He said they're bout a week or so from finalizing it. I'm not sure about ABS, I think he said they weren't offering it at this time but I could be wrong. I contemplated it, however I'm not sure I'm going to like the price tag for it. Even then, I'm still right back into the decision of whether or not I want to do this to a stock housing. ABS and E-Brake are not really in high demand for me. ABS is a deathtrap on one of these rigs with the way I have it set up and I cant remember the last time I used my e-brake haha. Plus, if I did a solid axle swap in the future, I'd be losing ABS anyways.

All things being equal, I would love the Diamond Axle, you can get it up to 3" wider than stock, and it is proven great quality. When I first bought my 3rd Gen I had the dream of doing an SAS and using the Diamond Axles, including the full floater in the rear.

One added benefit to the full floater is you can use front hubs and flat tow with no driveline rotation at all. HUGE if you flat tow behind the RV, as I do.

If the money isn't a problem, go for it!

:whipping2

The idea of a diamond is always nice. I haven't decided on width yet. I'd like to keep the width I have now as the 35's tuck nicely into the fender well. The reason I'm even considering a diamond setup is it's the route I would go anyways if I were to sas my rig, which isn't out of the question in the next few years. I can always add spacers in the future to widen the stance but even If I sas, I really don't want to go with larger than a 37" tire. I'd love to keep the cog low as possible, squatty and flexible. Money isn't necessarily the problem but it does play a factor as always. I mean, I obviously can't just go spend $5000 on stuff, but $3000 over the period of a couple months is not a huge problem for me. I actually just sold my rear CBI bumper to help fund the project. I can afford the fabricated diamond payment up front and buying the outer components over months time wouldn't be too hard for me. Wife might not be too happy, but tax returns should help ease the pain

 

[KidVermicious]

I think a full float conversion on an 8" housing is lipstick on a pig. But I think a diamond housing with an 8" center is wasted strength too. I say go big, diamond housing with a 9" center. Costs more up front, but you'll have ring and pinion strength to go with your axle strength.

 

[JWaldz]

I think a full float conversion on an 8" housing is lipstick on a pig. But I think a diamond housing with an 8" center is wasted strength too. I say go big, diamond housing with a 9" center. Costs more up front, but you'll have ring and pinion strength to go with your axle strength.

I'm starting to think the same way...

As far as, go big or go home, I could but at the same time that's another couple grand for a center setup with gears and ARB locker. I think plenty enough people run 35's or 37's on stock housings (and gears) without problems. Praying to the gods, I have yet to do it myself. If I grenade a rear end, I'm in a position I shouldn't be in. I wheel hard, but not that hard.

What's the weakest link when it comes to a a full setup diamond with chromoly shafts, chromoly spindles, chromoly hubs, chromoly drive flanges, arp hub studs, etc etc.... ?

 

[Singtoe]

I say do option C : Use a Land Cruiser rear end. Make new control arms to mount it it and be done.

It will have an E-locker (stonger then ours), disk brakes, floating axle and e- brake

 

[KidVermicious]

Is the LC 9" rear already full float? If so, Singtoe has the answer.

 

[JWaldz]

I say do option C : Use a Land Cruiser rear end. Make new control arms to mount it it and be done.

It will have an E-locker (stonger then ours), disk brakes, floating axle and e- brake

Only one thing wrong with that.. pumpkin is off-centered. Would take a little more fabrication than just links.

 

[JWaldz]

Is the LC 9" rear already full float? If so, Singtoe has the answer.

I think a specific couple of years were.. like 95+ maybe.. But still, pumpkins were off centered to pass side I think

 

[KidVermicious]

Passenger offset is away from the gas tank, so that's not a problem. Run CV joints on both ends of the driveshaft?

I'm just saying, if you can make it work it solves your want for a full float axle and adds mucho beef to the rest of the rear for about the same you were going to spend on the floater conversion anyway.

 

[1985taylor1925]

If youre going to be doing some custom fab, here are some more ideas.


http://www.toyota-4runner.org/3rd-gen-t4rs/209726-rear-coilover-long-travel-custom-linkage-thread.html

 

[URBAN ASSAULT]

I vote for the diamond housing. Good idea.

I wish I had gone with the diamond housing during the FF conversion, and again when I reworked the rear geometry. Just couldn't force myself to cough up the cash at those times. I will get it, someday, when I do a true 4 link in the rear.

I drooled over lots of rigs with Diamonds at the Jamboree. Top notch quality. Brian at FROR, and his staff, are great guys as well.

Sorry about the delay on the PM. I'll look over those links and check those part #'s for you.

 

[JWaldz]

I vote for the diamond housing. Good idea.

I wish I had gone with the diamond housing during the FF conversion, and again when I reworked the rear geometry. Just couldn't force myself to cough up the cash at those times. I will get it, someday, when I do a true 4 link in the rear.

I drooled over lots of rigs with Diamonds at the Jamboree. Top notch quality. Brian at FROR, and his staff, are great guys as well.

Sorry about the delay on the PM. I'll look over those links and check those part #'s for you.

You think going with a 8" Full Float Diamond with stock geometry is a smart move for now? Then maybe when I sas I can look at redoing the geometry on it. Perhaps do a f150 tank swap, move it to the back and get a true stable 4 link. The guys did bring up a good point and now I'm contemplating a rear centered 9.5" ff diamond and just source out a elocker 3rd and all the outer components. I can just have Brian come up with a mounting design to make is as "plug-n-play" as possible. I was going to build new upper and lower links anyways. The reasoning behind this is so I can go with a 9.5 front end later down the line when I decide to sas.

If I really wanted to make the mounting portion easy on myself I could go leafs and a trac-bar. Then later do a 4-link. Spring perches and shackles are easily welded and removed on an axle housing and frame.

Diamond Axle 9.5 Center Full Float FJC

 

[IBallEngineer]

You think going with a 8" Full Float Diamond with stock geometry is a smart move for now? Then maybe when I sas I can look at redoing the geometry on it. Perhaps do a f150 tank swap, move it to the back and get a true stable 4 link. The guys did bring up a good point and now I'm contemplating a rear centered 9.5" ff diamond and just source out a elocker 3rd and all the outer components. I can just have Brian come up with a mounting design to make is as "plug-n-play" as possible. I was going to build new upper and lower links anyways. The reasoning behind this is so I can go with a 9.5 front end later down the line when I decide to sas.

If I really wanted to make the mounting portion easy on myself I could go leafs and a trac-bar. Then later do a 4-link. Spring perches and shackles are easily welded and removed on an axle housing and frame.

Diamond Axle 9.5 Center Full Float FJC

Just curious why you'd want to go 9.5 in the front. My FJ62 had a 9.5 in the front but it was not a high pinion, one of the main reason I went with FZJ80 Axles was the high pinion in front. And I have V8 power, Air locked, and over 7000LBS. Not to say it can't be broken, I am very selective about locking my front axle, and I drive it like I expect it to take me home. Hey I'm all for the best options available, just wonderzin'.

:cheer2:

 

[Dirtco]

How many people have broken rear axles? I've yet to read of one. Not saying they don't just that it seems rare and doesn't seem worth the cost for something that pulls weekend crawler duty.

The axle shafts bend before they break (it's a known issue), it causes additional runout on the drum brakes and it kills the stock bearings and seals. I'm on my third axle housing, and I bent both of the stock axle shafts before I upgraded to the full float set-up.

You can brace the stock axle too.

Yes, you can truss the axle but it's tricky. You really need an axle alignment bar and pucks to do it right, I spent almost a month trussing my housing during my off time (to keep the heat down). I'm happy with the outcome, but it's not perfect.

I think a full float conversion on an 8" housing is lipstick on a pig. But I think a diamond housing with an 8" center is wasted strength too. I say go big, diamond housing with a 9" center. Costs more up front, but you'll have ring and pinion strength to go with your axle strength.

And this is why I have not invested in an aftermarket housing yet. I really like the full float kit, but you get to a point where you have to decide if the custom Toyota stuff is worth the money, or do you start looking at a manufactured 9" or maybe one ton axles?

 

[JWaldz]

Just curious why you'd want to go 9.5 in the front. My FJ62 had a 9.5 in the front but it was not a high pinion, one of the main reason I went with FZJ80 Axles was the high pinion in front.

Does Diamond not make a housing for a front HP 9.5". I was under the impression they did. I haven't investigated enough. The issue with running a stock front HP 9.5 is it's a passenger drop. It would take some $$$ to make that work.

Another thing to consider is the elockers in the cruisers are so temperamental. They end up taking a dump after a while.

 

[JWaldz]

And this is why I have not invested in an aftermarket housing yet. I really like the full float kit, but you get to a point where you have to decide if the custom Toyota stuff is worth the money, or do you start looking at a manufactured 9" or maybe one ton axles?

At this point, I think the best option for me is a 8" diamond with stock geometry. It may seem like a waste but plenty of people run 40's or bigger on stock 8" toy housings. They may have issues eventually but I would never want to run more than 37's anyways. I think a ff diamond 8" with chromoly parts would be plenty strong. I could eventually 4 link it when the times comes and getting a matching front axle for a SAS would be an easier swap. All parts would be interchangeable between front and rear for the most part as well.

It's more than lipstick on a pig but it may not be the Incredible Hulk of all setups. Should be plenty strong setup for slow crawling with the occasional skinny pedal with the 3.4. Would work well with dual cases/crawl box too.

Crawling over those curbs at the mall will still be difficult though....