Outer Limits 4x4 Board

what's available for the landcruiser 9 inch diffs in regards to stronger pinions? sick of damaging them. did a few on stock drivetrain and 33's.

snapped one a beuty first trip out on 36's with the falcon 6 conversion this weekend. i want to be able to set and forget...

im looking at putting a GQ front end in mine, CVs are easyer to change than diffs

are you twisting and snapping the pinion just behind the tail shaft flange?

duck wrote:im looking at putting a GQ front end in mine, CVs are easyer to change than diffs

its the rear... and i'm not looking at throwing new diffs under there.

hulsty wrote:are you twisting and snapping the pinion just behind the tail shaft flange?

that's exactly where it's failing.

bad_religion_au wrote:are you twisting and snapping the pinion just behind the tail shaft flange?
that's exactly where it's failing.

how is this happening? are the uni's binding? I am yet to see a pinion snap from sheer power, generally something else fails first...
changing to nissan is no advantage, they run the size same pinion bearings, but the material hardness is generally a little higher which usually results in more pinion failures. The only downside in cruiser rears is the wall thickness of the small bearing end of the housing, and this often become loose. IMO find out the real reason that is causing them to fail first!

last resort upgrade to toyota dyna/tundra 10.5" rear

In there area that is breaking is there a diameter difference between 4.11 diffs and 4.1 diffs ? Or are they all the same aside from the ratio difference.

I *think* that the later cruiser ie 100 series 78/79 series have a larger diameter in the area that is breaking than the earlier diffs. Might be possible to swap out the side gears to work with your axels.

I have been doing the same thing in my BJ42 but in the front diff. I have done three this year, all exactly the same. No twist, a straight snap just after the flange of the driveshaft.

After this last snap (a week ago), I rang superior and after he spoke to some other people (which actually might have been 1madengineer) it was suggested that because the brackets on the springs are too high (too allow the leaves to separate for more flex) it is allowing the diff to twist (axle wrap) causing too much angle in the driveshaft, snapping the pinion. It is a good theory as each snap has been when there was a high impact on the front diff, where the front tyres hit an obstacle, gripping but not going anywhere.

This might not help the case for the rear diff however it's something to consider. Mick also reckoned there was aftermarket gears that could be freeze treated to make them stronger. This included the pinion. He is yet to send me a price.

I am still working out my solution, hope this helps...

That stands to reason, in my rear I totalled two pairs of springs due to axel wrap. I was surprised I didnt damage a pinion. I have now moved upto quality springs, with the appropriate clamps and have no more issues regarding axel wrap like I was.

1MadEngineer wrote:

bad_religion_au wrote:are you twisting and snapping the pinion just behind the tail shaft flange?
that's exactly where it's failing.

how is this happening? are the uni's binding? I am yet to see a pinion snap from sheer power, generally something else fails first...
changing to nissan is no advantage, they run the size same pinion bearings, but the material hardness is generally a little higher which usually results in more pinion failures. The only downside in cruiser rears is the wall thickness of the small bearing end of the housing, and this often become loose. IMO find out the real reason that is causing them to fail first!

last resort upgrade to toyota dyna/tundra 10.5" rear

the last one was probably was uni's binding due to spring wrap, as i was testing the soft springs on a big climb, but the other ones i'm not convinced were. i'm definately going an anti-wrap bar after the weekend, but having cracked and busted them before i had enough traction/tire/flex/power to have any axle wrap, i'd still like something stronger if available (like i said, do it right, do it once!).

i remember reading about cryo'd pinions ages ago on a yank site, but can't remember if that was for the hilux's or cruisers.

I haven't done a front pinion yet and my spring clamps are opened up with 2 leaves removed out of each of the front packs so they are pretty soft. I do use a cut down 60 series double cardin front shaft though...

RAY185 wrote: I do use a cut down 60 series double cardin front shaft though...

That might be the ticket. What series did these come out in? Many around? I am loathed to reduce my flex, it will seriously disadvantage me next year in Tough Tracks.

Be careful, a DC joint has less working angle than a single unis.

I tried to fit a 60s DC joint on the front of my cruiser to stop high speed vibes. But it wouldn't work at the angles that i wanted.

Z()LTAN wrote:Be careful, a DC joint has less working angle than a single unis.

I tried to fit a 60s DC joint on the front of my cruiser to stop high speed vibes. But it wouldn't work at the angles that i wanted.

you can get the yota DC's to pretty much the same angles as regular uni's with a bit of clever material removal.

did you cut and turn the axles when you sprung it over? there shouldn't be too much of a driveshaft angle if you did.

RAY185 wrote:I haven't done a front pinion yet and my spring clamps are opened up with 2 leaves removed out of each of the front packs so they are pretty soft. I do use a cut down 60 series double cardin front shaft though...

i'm using a 60 series DC in the rear, which is the one i broke.

bad_religion_au wrote:

RAY185 wrote:I haven't done a front pinion yet and my spring clamps are opened up with 2 leaves removed out of each of the front packs so they are pretty soft. I do use a cut down 60 series double cardin front shaft though...

i'm using a 60 series DC in the rear, which is the one i broke.

Then I would guess you are on the right track building a anti-wrap bar. Although in saying that, I don't know how soft your suspension is setup in the back.

Rick- Not sure what models they are in. Mine came out of an 84 FJ60 I wrecked, but I had another 84 FJ60 in the other day which had a normal front shaft. Last time I checked, Ford, Holden & 4x4 Wrecking at Brendale had a couple. 3205 4377

Could pinion support be an issue? I've noticed the cast differential centre carriers change as the years go on. My newer carriers have extra casting that extends upto the pinion further than the earlier carriers.

I used to be able to get enough axle wrap in the rear of my dead stock FJ40 to snap the pinion hitting second gear hard from traffic lights. Running 31" Desert Duelers.

Axle wrap and uni bind is the killer of Toyota pinions. Excessive Traction has little to do with it.

RUFF wrote:
Axle wrap and uni bind is the killer of Toyota pinions. Excessive Traction has little to do with it.

So what is the best solution?

No consensis yet on DC yet, but might help.

Freeze treated gears??? Surely this must help.

Adjusting the springs, i.e. tighter clamps on leaves???

Anti axle wrap bar???

Is it some or all of these to stop the problem? Or do we just have to drive a little more pedestrian. I bloody hope not...

axle wrap bar.

from my research, later pinions are finespline, supposed to be tougher.

Longfield offers a heat treating/cryo service.

even when i take care of the axle wrap, i still want beef, so i'll end up going this route.

Ricko wrote:

RUFF wrote:
Axle wrap and uni bind is the killer of Toyota pinions. Excessive Traction has little to do with it.

So what is the best solution?

No consensis yet on DC yet, but might help.

Freeze treated gears??? Surely this must help.

Adjusting the springs, i.e. tighter clamps on leaves???

Anti axle wrap bar???

Is it some or all of these to stop the problem? Or do we just have to drive a little more pedestrian. I bloody hope not...

I ran a stock 80 series rear centre in my buggy.



The above pic was taken when Dave Camp drove it at the 2006 World Finals in Las Vegas. Most people will prob attest that i drove it harder than Dave when i was still driving it. The 80 series centre is stronger in other areas but the pinion failure point is exactly the same. Right behind the flange. I snapped one pinion in 2 years of competition abuse. This was caused due to the uni binding and happened within the first couple of comps. Dave then drove the car for 18 months before going to Dana 60 diffs and never broke another centre. The only reason for the upgrade was for larger and stronger axles and more steering lock.

Fix the axle wrap and you should fix the Uni Bind. This in turn should fix your problem.

I dont think you need to treat the gears or fit a DC shaft.

bad_religion_au wrote:axle wrap bar.

from my research, later pinions are finespline, supposed to be tougher.

Longfield offers a heat treating/cryo service.

even when i take care of the axle wrap, i still want beef, so i'll end up going this route.

I have seen the course spline pinions take a lot of abuse in competition use. As long as the splines have no wear and the pinion is tight they rarely fail. But the fine spline pinions are the pick if your replacing centres.

RUFF wrote:

bad_religion_au wrote:axle wrap bar.

from my research, later pinions are finespline, supposed to be tougher.

Longfield offers a heat treating/cryo service.

even when i take care of the axle wrap, i still want beef, so i'll end up going this route.

I have seen the course spline pinions take a lot of abuse in competition use. As long as the splines have no wear and the pinion is tight they rarely fail. But the fine spline pinions are the pick if your replacing centres.

well i gotta replace it anyway i'm out of spares.

going to take the opportunity to regear to 4.88, ordering them from the states, so won't cost me any more for shipping to get them cryo'd. i thought it'd be worth the extra $40 to get at least the rear cryo'd, but i've watched you drive RUFF, so the fine spline pinion set up right should be enough.

RUFF wrote:

Ricko wrote:

RUFF wrote:

Fix the axle wrap and you should fix the Uni Bind. This in turn should fix your problem.

I dont think you need to treat the gears or fit a DC shaft.

Well that would suit me. I already have a couple more centres available. It will cost a bomb for the hardened gears, not to mention cutting down another shaft.

I have already had a look at the superior website and they do one for the 40# at $450. Since I am not real flash at making/designing this sort of gear, it will be the go for me I think. Plus it was superior who initially led me down the axle wrap path, service should equal sales.

Sorry bad_religion_au for semi-jacking your post, but since i had exactly the same issue and am trying to sort it right now also, I really had no choice.

I'm still open to more ideas about this, but at this stage I am going for the wrap bar, and standard gears.

Cheers, Rick.

bad_religion_au wrote:

Z()LTAN wrote:Be careful, a DC joint has less working angle than a single unis.

I tried to fit a 60s DC joint on the front of my cruiser to stop high speed vibes. But it wouldn't work at the angles that i wanted.

you can get the yota DC's to pretty much the same angles as regular uni's with a bit of clever material removal.

did you cut and turn the axles when you sprung it over? there shouldn't be too much of a driveshaft angle if you did.

Yes i have cut and turned.

These are old pix and the ride height has come down somewhat since then.

Its my Trans end unis thats the problem... its almost binding at ride height... remember the 13" lift thread

Trans end


Diff end

bad_religion_au wrote:ordering them from the states

Where are you shopping?

Was it like this vid clip

http://www.youtube.com/watch?v=VQtc-QS0 ... re=related


if you read some of the comments a bloke says about a axel wrap bar

The hilux dc joints get heaps more angle then the standard 75's uni's not shore if its early or late model ones are better but one is. I had the same problem as Z()LTAN with my FJ73 and fixed it with that and i have heaps of front axle movement its also running a wrap bar.

HANCOCK wrote:The hilux dc joints get heaps more angle then the standard 75's uni's not shore if its early or late model ones are better but one is. I had the same problem as Z()LTAN with my FJ73 and fixed it with that and i have heaps of front axle movement its also running a wrap bar.

lux ifs dc = ~25-30deg
lux solid ax dc = ~35-37deg
some 60 series rear long ear = 45deg+

Z()LTAN wrote:

bad_religion_au wrote:

Z()LTAN wrote:Be careful, a DC joint has less working angle than a single unis.

I tried to fit a 60s DC joint on the front of my cruiser to stop high speed vibes. But it wouldn't work at the angles that i wanted.

you can get the yota DC's to pretty much the same angles as regular uni's with a bit of clever material removal.

did you cut and turn the axles when you sprung it over? there shouldn't be too much of a driveshaft angle if you did.

Yes i have cut and turned.

These are old pix and the ride height has come down somewhat since then.

Its my Trans end unis thats the problem... its almost binding at ride height... remember the 13" lift thread

well you need something in there, you can't run a non DC/CV shaft with the uni's at THAT much of a different angle.

vk7ybi wrote:

bad_religion_au wrote:ordering them from the states

Where are you shopping?

Randy's Ring & Pinion