FZJ105r DIFF TALK

[SCANAS]

What ratio diff is in my FZJ105r (solid axle GXL petrol auto )

Half the net says 4.11 half says 4.33

Yeah I know I should pull it out and count some teef but when I pull it out, I want to throw another one in there so I can keep driving it, fix the broken one with better bits and swap them back.

A04B is the axle code - And depending on what decoder you put that into it tells me different things a 3.56 - 4.11 - 4.1 - 4.56 ??????

[Stackson45]

If you have to jack it up, mark driveshaft and tyre, rotate the wheel one complete revolution and count the tailshaft turns. You will see the difference between those ratios.

[SCANAS]

I've already taken the cvs and axles out.

[Stackson45]

If cv's and axles are out i assume you're not driving it right now? you're only ten minutes and a few bolts away from having the centre out and ratio counted.

[Stackson45]

If cv's and axles are out i assume you're not driving it right now? you're only ten minutes and a few bolts away from having the centre out and ratio counted.

[RED60]

If you have to jack it up, mark driveshaft and tyre, rotate the wheel one complete revolution and count the tailshaft turns. You will see the difference between those ratios.

Please expand on how the above method helps on finding the actual ratio......

I do agree the OP should pull the centre and count if it's that far already.....

[Stackson45]

If you have to jack it up, mark driveshaft and tyre, rotate the wheel one complete revolution and count the tailshaft turns. You will see the difference between those ratios.

Please expand on how the above method helps on finding the actual ratio......

I do agree the OP should pull the centre and count if it's that far already.....

Your diff ratio 4.56:1 equates to as we all know 4.56 rotations of the pinion to 1 of the crown = driveshaft to axle. This is just a way to check that.
Not precise to decimals, but if you just want to check without stripping the thing down...


With a locked (or tight limo centre) raise the axle (front or rear whichever you're trying to count) both wheels just off the ground.
Mark one wheel at the bottom, and a corresponding mark on the ground.
On the pinion, mark the flange and corresponding point on the housing - these will be your datum points.

Spin the wheels one full turn slowly, back to the datum mark, and count the pinion (driveshaft) rotations as you go - may need the help of a friend, or lie down so you can see both.

You will count either approx 3 and a half, just over four, or four and a half driveshaft rotations for the one turn of the wheel for the ratios 3.56, 4.1/4.11, 4.56 respectively.

Can someone clarify if an actual 4.1:1 was available? 41t crown to 10t pinion? your standard cruiser teeth are 37:9 (= 4.1111111111etc:1) i remember some debates about this but don't recall if anyone found an example.

This only works with KNOWN AVAILABLE diff ratio values - or will give you a ball park of what the ratio might be if the available is unknown.

With an OPEN centre, leave one wheel on the ground, mark the raised wheel and pinion, but rotate the raised wheel TWICE and count the tailshaft rotations.

Or pull it out and count....

[SCANAS]

I'm still driving it. I know the technique mentioned. I want to buy another diff and put it in at the same time, surely someone knows its a 4.33 or 4.1 or 4.11

[SCANAS]

99% sure all petrol auto 80/105s all wheel drives will have the same ratio, just need to know what it is exactly.

[crankycruiser]

ALL 105s ran 4.3. Unless someones put aftermarket ratios in.

ALL 80s were 4.11 regardless of motor, box, or model

[SCANAS]

Cheers Cranky, i'm off to shop for a 4.33!

[SCANAS]

Just paid for a diff from the boys at Minden, best price around!

Then to swap them and hopefully the broken one can be fixed with better bits, yukons, solid spacer and the correct preload, sadly I don't think a locker is in the budget.

How much preload is recommended?

[Hilux_Ryan]

up until 60s they are 4.11(37/9), then with 80s they go to 4.10(41/10), then 105 go 4.30(43/10) and 100 go 4.10 this is for diesels, and pretty sure petrol uses same ratios.

(they change from 4.11 to 4.10 as for virtually the same ratio more teeth means more contact means quieter and stronger)

[bazzle]

Dont forget to check before you put it in...just in case

[SCANAS]

Old diff has 3 broken teeth.

The 2nd hand diff I bought is going in now after having a new set of bearing put in. Really wanted to see what the problem was with the old one before spending money.

See how this one goes otherwise i'll bust out the wallet and get nitro gears and maybe more

[SCANAS]

For what's it's worth I PM'd a few of the guys who always chime in saying they are the god of 8" landcruiser diff and they know all the tricks etc to ask them about how much preload needs to used and none replied.

So how much preload should be used?

And do you really need a locker to replace the 2 pinion carrier?

Or will a set of Nitro Gears ( which brand to use? ) and a spacer do the trick?

An ARB with compressor is going to cost at least $1200 extra probably closer to $1500. A cheaper locker and part time kit about the same price.

[Shadow]

The 2 pinion carrier has 2 big hollow section in the carrier.

at these hollow sections the ring gear can deflect slightly from the pinion under extreme loads, and bang goes a few teeth.

were the teeth missing nexto one of the big holes in the carrier on your old diff??

the solution is a 4 pinion carrier. Either toyota open diff carrier, or aftermarket locker.



below is a set of 4 pinion carriers from a 105, the bigger one is the rear 9.5", smaller one the front 8"



as for torque settings try this site

http://www.gearinstalls.com

or specifically a 80 series front gettin g new gears http://www.gearinstalls.com/nick.htm

[SCANAS]

Ok so standard geasr fine as the locker and spacer will keep it all tight?

[SCANAS]

Yeah I know the difference. Not sure if where my teeth are broken is much of an indication as we had to get the car out of the creek and into a paddock so it drove about 100m and it's full time so the the gears would have been rotating I assume. But I see your point.

If I could get 4 pinion centre would that work by itself or are more parts required / ratios interchangeable etc? Which model would I look for?

[Shadow]

Ok so standard geasr fine as the locker and spacer will keep it all tight?

The standard 4 pinion carrier is as strong as a locker basically.

but a locker, once locked, wont let one wheel over spin to double speed and then bite down causing the bang, so a locker is always stronger(when locked).


As for the solid pinion spacer, the science just isnt there to prove it helps strengthen the diff.

The spacer exists ONLY so that the pinion nut doesn't move. It gives the nut something to tighten against, giving the face of the nut friction, so that it doesnt turn,

If the pinion nut loosens, the preload on the pinion bearings reduces until the pinion is loose and moving freely away from the ring gear, which then quickly blows gears off the ring and pinion.

People will argue till they are blue in the face, and many guys on here with alot of experience with diffs will tell you they are worth thier weight in gold. But the science just isnt there to support it.

If I was going to have a couple diffs built i would use a solid spacer since im no expert, but im far from convinced of its magical powers.

I would not use a solid spacer with shims, i would use a lathe to turn the spacer to the correct length.

[SCANAS]

Ok so standard geasr fine as the locker and spacer will keep it all tight?

The standard 4 pinion carrier is as strong as a locker basically.

but a locker, once locked, wont let one will over spin to double speed and then bite down causing the bang, so a locker is always stronger.

Yep, understand that 100%

As for the solid pinion spacer, the science just isnt there to prove it helps strengthen the diff.

The spacer exists ONLY so that the pinion nut doesn't move. It gives the nut something to tighten against, giving the face of the nut friction, so that it doesnt turn,

If the pinion nut loosens, the preload on the pinion bearings reduces until the pinion is loose and moving freely away from the ring gear, which then quickly blows gears off the ring and pinion.

People will argue till they are blue in the face, and many guys on here with alot of experience with diffs will tell you they are worth thier weight in gold. But the science just isnt there to support it.

If I was going to have a couple diffs built i would use a solid spacer since im no expert, but im far from convinced of its magical powers.

I would not use a solid spacer with shims, i would use a lathe to turn the spacer to the correct length.

Not that I have much a clue re building a diff but if the collapsable spacer softens and flexs than the nut is going to loose tension yeah?

But that's all good info. 2nd hand 4 pinion carrier is around $500 plus installing it Vs an extra $1000 for the air locker. The budget would allow a locker if I don't need gears as suggested so that's what I'll do next. I'll run with this reco'd one for few months save some funds.

[Shadow]

Yeah I know the difference. Not sure if where my teeth are broken is much of an indication as we had to get the car out of the creek and into a paddock so it drove about 100m and it's full time so the the gears would have been rotating I assume. But I see your point.

If I could get 4 pinion centre would that work by itself or are more parts required / ratios interchangeable etc? Which model would I look for?

I think all VDJ vehciles have the 4 pinion, and alot of HDJ/HZJ/FZJ 78/79/105 did.

I have heard everything after August 02 had 4 pinion carriers, but theres also some people who claim to have cars after that build date with 2 pinion carriers. (who knows if someone replaced the diff with an 80 series before they got it though)

[Shadow]

Not that I have much a clue re building a diff but if the collapsable spacer softens and flexs than the nut is going to loose tension yeah?

But that's all good info. 2nd hand 4 pinion carrier is around $500 plus installing it Vs an extra $1000 for the air locker. The budget would allow a locker if I don't need gears as suggested so that's what I'll do next. I'll run with this reco'd one for few months save some funds.

I just bought a rear diff for my 100(ifs) in 4.10 ratio for $400. From LCOOL forums. There was a matching front diff too if you want me to find out if its available?

bargains are around.

http://www.lcool.org/forum/viewtopic.ph ... highlight=

you might have to register. His add says it an 80 series diff but the rear diff i got off him was definately from a later cruiser.

[SCANAS]

Would it work for a 4.33 is there any differences?

[SCANAS]

Added this thread to the cruiser bible.

[SCANAS]

Thanks, Waiting on confirmation of LCOOL Admin

[Shadow]

Would it work for a 4.33 is there any differences?

theres no difference, just the gearset

[SCANAS]

Would it work for a 4.33 is there any differences?

theres no difference, just the gearset

Are the splines the same, would this work.

http://www.ebay.com.au/itm/Toyota-Landc ... 225wt_1399" onclick="window.open(this.href);return false;

[Shadow]

i believe so

To check, if the ARB locker for your car also fits the car those centre are from, then it will work in yours.

[slosh]

Could a Hilux rear 4.3 lsd centre be used for parts to convert the Cruiser front to 4 pinion?