FJ40 Rear Axle Research (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

M

Mr. Notorious

Joined
Apr 19, 2006
Threads
32
Messages
154
Starting the new year I'll be gathering parts for my mild spring build. The plans are to run coil overs front and rear and link it up. I'm running a chevy 350, a sm465, then adapted to a toy 3 spd case to keep the offset rear axle.

So right now I'm looking for a axle swap that will give me more width for stability, but also allow my center section from my current FJ40 stock (as far as I know) rear axle. It has gears with an ARB, thats why I'm pushing to keep it.

I heard about a FJ80, will it work? Any others? Can anyone answer the questions about the FJ80 or another axle they suggest?

Can the center section drop in?

Will the axle shafts have the same spline count as my stock FJ40's ARB's?

Does it have disc brakes? Easy to convert?

Same wheel bolt pattern as my FJ40?

Any big strength differences? (decrease or increase)

Ebrake mechanism?



A side question: if the ebrake is moved to the axle, is there an easy/cheap way to remove the one on the back of my t-case?

Thanks for the help, keep an eye for the suspension tear down in a few weeks :bounce:
 
60/62 series rear axle will be 3" wider....IIRC, stock is 55", 60/62 is 58"

centers interchange 100%...you'd need rear shafts for the 60, but they are 30-spline, same as the 40....likely your easiest swap option.
 
Thanks for the reply. What years are these series (yes I'm a little rough on non- FJ40 stuff ;))?

Any other wider options? I was looking to gain 3" on each side. I already have 3" overall on the rear from wheel spacers. I would like to throw the wheel spacers on the front, and get a 6" wider rear overall to match.
 
Could save yourself a bunch of cash and run a centered output t-case.. Dime a dozen, and cheap to fit to a 465.

Then, center your rear axle using minitruck parts. Since the '86+ axles are 3" wider, you can use those shafts, keep your FJ40 center chunk, Your disc brakes should just about bolt-up, yadda yadda.. Use your current spacers, and viola! 6" wider.

Your total outlay of parts would be a minitruck rear axle for ~$150-200, sell the stock third for $50-75, a Chevy t-case that mates to the 465, and that's about it..
 
2" offset wheels and a 60 series axle nets you 7".


Sell your wheel spacers.


:beer:
 
Eskimo said:
Could save yourself a bunch of cash and run a centered output t-case.. Dime a dozen, and cheap to fit to a 465.

Then, center your rear axle using minitruck parts. Since the '86+ axles are 3" wider, you can use those shafts, keep your FJ40 center chunk, Your disc brakes should just about bolt-up, yadda yadda.. Use your current spacers, and viola! 6" wider.

Your total outlay of parts would be a minitruck rear axle for ~$150-200, sell the stock third for $50-75, a Chevy t-case that mates to the 465, and that's about it..
Click to expand...

You just threw a wrench in my plan; but you do make a good point. Plus my transfer case is most likely the weakpoint from what I gather... You really think it would be cheaper to do a t case and a mini truck axle swap than a FJ60 swap with wheel spacers? Anyone chime in about a good swap? I knida like the D300...

The reason for the wide axle, would be to out board the coil overs as far as possible, mainly for stability reasons. I know I'll most like have to chop the rear frame section and fabricate a narrowed section to clear the coil overs. Wheel spacers help, but not as good as giving me a wider axle to weld on some coil over tabs further out.

I unfortunatly just bought my wheels, or else I wouldn't mine buying some more offset wheels.

So my center section bolts into a mini truck axle too? Are the mini truck axles comparable in strength to my LC's?
 
Mr. Notorious said:
So my center section bolts into a mini truck axle too?
Click to expand...


No it will not.

You will need to make or purchase a custom housing to use a Land Cruiser center section with the mini truck axles and brakes.




Mr. Notorious said:
Are the mini truck axles comparable in strength to my LC's?
Click to expand...


Yes, and you can upgrade to Chromo from Poly Perf. which would be a good idea.



Get a Dana 300 and install 32 spline outputs in it for sure, and possibly a lower gear set, and don't look back.


(or pick up a STAK or Atlas) ;)



Good luck!


-Steve
 
Poser said:
No it will not.

You will need to make or purchase a custom housing to use a Land Cruiser center section with the mini truck axles and brakes.







Yes, and you can upgrade to Chromo from Poly Perf. which would be a good idea.



Get a Dana 300 and install 32 spline outputs in it for sure, and possibly a lower gear set, and don't look back.


(or pick up a STAK or Atlas) ;)



Good luck!


-Steve
Click to expand...

Hmm, thanks for the response. Since the biggest issue for me is keeping the current center section, the centered minitruck rear isn't feasable, and then doesn't justify a 4:1 twin stick d300 :crybaby: I can't think of any other centered rear axles I like... 60's have a huge pumpkin and different bolt pattern, 44's aren't much of a gain.

Anyone know the width of a FJ80 rear axle? Or am I pretty much narrowed down to just FJ60 for the easiest compadability? Are 60 series shafts any stronger than the FJ40's?
 
All the rear shafts are the same spline, but the mini's have a constant size throughout the shaft, and they tolerate TONS of abuse since they'll twist evenly.

Look through the tech writeups, Woody did a centered rear on his rig.. it's the best of both Toyota worlds.. Cruiser center section, minitruck shafts.

FJ80 rears aren't THAT offset, either.. another option. they are low 60's.. I know the front was 63.5"
 
Mr. Notorious said:
Starting the new year I'll be gathering parts for my mild spring build. The plans are to run coil overs front and rear and link it up. I'm running a chevy 350, a sm465, then adapted to a toy 3 spd case to keep the offset rear axle.

So right now I'm looking for a axle swap that will give me more width for stability, but also allow my center section from my current FJ40 stock (as far as I know) rear axle. It has gears with an ARB, thats why I'm pushing to keep it.

I heard about a FJ80, will it work? Any others? Can anyone answer the questions about the FJ80 or another axle they suggest?

Can the center section drop in?

Will the axle shafts have the same spline count as my stock FJ40's ARB's?

Does it have disc brakes? Easy to convert?

Same wheel bolt pattern as my FJ40?

Any big strength differences? (decrease or increase)

Ebrake mechanism?



A side question: if the ebrake is moved to the axle, is there an easy/cheap way to remove the one on the back of my t-case?

Thanks for the help, keep an eye for the suspension tear down in a few weeks :bounce:
Click to expand...

I just put an 80 series rear in my 55, which has the same axles as a 40. I also put a 80 series rear locker in my front diff.

The center section on the rear of the 80 is identical to anything else in a Land Cruiser.

The center section on the front of the 80 is a high pinion, smaller third identical to a mini rear. A rear 80 will fit and work fine in the front of a 4/5/6x diff, but a 4/5/6x front third will not work in an 80 front axle.

axle shaft spline count depends on the year of your 40/ It is the same as a fine spline 40.

93+ 80s have discs front and rear. 92 down have drums in the rear

all 60s and 80s have drum e-brakes located in the rear wheel. 93+ 80s have e-brake only drums located inside the rotor hats.

The bolt patterns are identical, but 80 rear calipers will have be ground a lot or 16 inch rims are needed.

80 front axles and birfs are considerably stronger than stock 40 or 60 fronts. 93+ rears are all full floaters.

You can just take the e-brake stuff off the back of your transfer case. You will need to keep the drum unless you go to a later year output yoke.


The 80 axles are about 8 inches wider than a 40 axle. I gained about 2" over my stock 55 with 2" spacers on either side.


There is a LOT of stuff to cut off an 80 axle. Expect to spend a day grinding it all down.

The 80 axle will also offset your driveshaft a couple of inches. A 60 axle will too, but I don't think as much.
 
I would keep it simple. FJ60 axles, PIG ChroMo inners, wheelspacers or offset wheels. It doesn't get any simpler and should be plenty strong. If you need stronger, then it's time to abandon the Land Cruiser axle entirely and head over to Dana 60s with all the custom options.

FJ60 axle as above will not be expensive as axles go.
 
Gumby said:
You can just take the e-brake stuff off the back of your transfer case. You will need to keep the drum unless you go to a later year output yoke.
Click to expand...


What flange did you have in mind for this?


The output shaft splines of the one-piece case are not the same number or diameter, compared to a split case rear output flange...



:beer:
 
I love my Cruiser/Mini Hybrid, and Dana 300..

A Cheep way to do it is a Stock minitruck Axle, Keep the Drum brakes (So you have an E-brake). Dana 300 with 32 spline R output, you can always add 4:1, and front 32 later down the road..

I ended up with a Cruiser 3rd member and Disks, but its not that much stronger than a Mini center, and i have no way to do an EZ E-brake.

I was happy to get away from the Cruiser Case, (it would become the week link, and they have NO aftermarket support)..

another option is Minitruck T-case.. Strong, Cheep to get/upgrade, and good aftermarket!
 
my 77 case was 16-spline and case drum e-brake....so was my 74....
 
You must log in or register to reply here.

Similar threads

P
Rear coilovers on a 40 ?
Replies
16
Views
1K
Blackknight1
Blackknight1
Rock40
Old and New: 5.7 Vortec to 6.0 LS Swap, ‘69 FJ40
4 5 6
Replies
114
Views
7K
Rock40
Rock40
Choo Magoo
How much is too much side to side movement of axle during 3 link suspension axle travel?
Replies
11
Views
2K
Choo Magoo
Choo Magoo
SaturnAscends
Should the third member be dropped to replace the pinion seal on an 8.4” rear diff?
Replies
4
Views
392
WildernessRimFab
WildernessRimFab

Users who are viewing this thread

Total: 2 (members: 0, guests: 2)

Share this page

Back
Top Bottom