[tanshi]

Can any one tell me where i can get the solid spacers for the diff pinions on sierra diffs? i want to build up the diffs a little stronger than the collapsable spacers will allow. I have heard of people doing them in diffs but have never managed to find them for sale.

[Gwagensteve]

I'm not sure they are an off the shelf part - If they were, you'd theoretically need shims to get the pinion depth right.

Matt from total traction drivelines in Moorabbin (Vic) has set up quite a few for club members here.

Steve.

[royce]

they have to be machined to suit your pinion in your housing

I am yet to understand what they are supposed to do, both pinion bearings oppose each other and cant move anywhere

[tanshi]

theoretically the crush spacer can crush if you put enough torque through them. With a soild spacer that cant happen

[royce]

but how can it crush? what crushes it? the spacer has no drive through it thats what the pinion does

[tanshi]

i would think that the pinion turning, against the crown wheel pushes back away from it? if you put enough torque through it some thing has to give, and the spacer would presumably be the point of weakness?? not the best description but it may help explain it

[royce]

if the pinion is able to move then the preload wasnt correct to start with and with a solid spacer it would just clunk and flog the bearings anyway

I reckon its the answer to a question nobody asked

by this reckoning sierra front wheel bearings should have a solid spacer between them as well

[Gwagensteve]

royce wrote:

but how can it crush? what crushes it? the spacer has no drive through it thats what the pinion does

Torque. Much more torque and much more traction than suzuki designed the diff for results in lots of thrust on the pinion as the pinion tries to push away from the crownwheel. At large loads, bearing deflection occurs and the crush sleeve collapses. Have a look at how many sierras with lockers in the rear have loose pinions. They never have loose pinion nuts - the tabs will still be peened over just as they were from the factory- the nuts didn't loosen

A stock sierra can theoretically put 800Nm into the pinion.

A sierra with an EFI 1.6 and a 6:1 can put 3000Nm into the pinion.

Now jam some 34's up with a locker and that's a lot more thrust than suzuki were planning.

Steve.

[tanshi]

Gwagensteve wrote:

royce wrote:

but how can it crush? what crushes it? the spacer has no drive through it thats what the pinion does

Torque. Much more torque and much more traction than suzuki designed the diff for results in lots of thrust on the pinion as the pinion tries to push away from the crownwheel. At large loads, bearing deflection occurs and the crush sleeve collapses. Have a look at how many sierras with lockers in the rear have loose pinions. They never have loose pinion nuts - the tabs will still be peened over just as they were from the factory- the nuts didn't loosen

A stock sierra can theoretically put 800Nm into the pinion.

A sierra with an EFI 1.6 and a 6:1 can put 3000Nm into the pinion.

Now jam some 34's up with a locker and that's a lot more thrust than suzuki were planning.

Steve.

Thats what i said

[tanshi]

http://www.pirate4x4.com/forum/archive/ ... 39743.html

found this on pirate. any chance thats these guys are right and a toyota 7" spacer would work? i know you can get these after market.

[royce]

no, thats wrong, its worse than wrong its plain retarded

if the bearing flexes (giggle) then its fucked
when a bearing wears the bits get smaller so the preload get lighter and shit flops around and its fucked, thats not the spacer

to crush the spacer you need to push both pinion bearings in towards each other, to do this you need to COMPRESS THE FUCKING STEEL DIFF CARRIER and apply that compressing force between the end on the pinion gear and the diff flange, how do you apply force in that direction when one end hovers in free space and the other has a spinning shaft attached that is designed to change length as it goes?

you know suzuki owners are the only people world wide that think these things are for some kind of horespower remedy dont you?

[tanshi]

so the reason they make solid spacer kits for luxes is??

[Gwagensteve]

The fact you think we're doing this as a "horsepower fix" is as dumb as claiming the carrier has to bend to allow a bearing to deflect under heavy thrust loads. Under your reasoning, larger tyres couldn't cause more rapid wheelbearing failure because the the hub would have to bend for the bearings to deflect and loosen off.

Bearings can and do deflect, and you're right, that does wreck them. Preventing the bearings from being able to deflect when loaded outside of their design parameters is why you'd run a solid spacer. The crush sleeve is there to set preload. If that preload is defeated by the force acting on the bearing from the opposite direction (i.e thrust) you'll loose that preload, the pinion starts to walk and loose pinions, wrecked gears and leaky seals are the result.

AFAIK it's only sierra and hilux diffs (out of common 4WD diffs) that use a crush sleeve to set bearing preload and funny enough, they're the ones that get converted to solid sleeves.

Anyway, it works for us in Vic. Solid spacers result in tight pinions and seals that last.

Steve.

[joeblow]

Gwagensteve wrote:

AFAIK it's only sierra and hilux diffs (out of common 4WD diffs) that use a crush sleeve to set bearing preload and funny enough, they're the ones that get converted to solid sleeves.

Anyway, it works for us in Vic. Solid spacers result in tight pinions and seals that last.

Steve.

Pretty much ALL banjo type differentials (removable third members), and dana types use a collapsable spacer. Old Tojos had them, then they went to a collapsable version. If you are constantly having problems with pinions you either need to look at the vehicle setup and or driving style. Going to a larger diff may be the only way to solve this. Myself and others I know who build diffs will not use solid spacers. Measuring for a solid spacer is critical, and being slightly off in shimming will destroy the diff quick. Another reason we don't use them is the deflection is then taken up by the ring gear resulting in breakage. I would rather my pinion come loose than a gearset failing in the bush. Funny thing, of all the diffs I build loose pinions are not a problem.


Also, as an experiment, pull apart a diff that has a loose pinion, and one that is normal. I bet there is a 99% chance the spacers will be of the same height, and only the bearings have suffered damage.

A pinion that deflects away from the ring gear, towards the pinion flange will strain the main large bearing, if that moves the collapsable spacer will then move the small bearing out towards the seal, and as there is nothing behind the small bearing to stop it the spacer should not collapse at all, but you're large pinion bearing will be toast. Sme applies to opposite direction but substitute large for small bearing.

[royce]

http://www.4x4wire.com/toyota/tech/crush_sleeve/

your wheel bearing analogy is also wrong, that would be like bolting a 10kg weight to the pinion flange

[Gwagensteve]

No it's not royce, the analogy is that an overloaded bearing assembly looses its preload even if that's theoretically impossible. The bearings in a hub oppose each other too so it should be impossible for them to loosen once preloaded, but if the force on the bearing is greater than the preload they loosen off.

Steve.

[royce]

the bearings dont loosen, they wear and therefore get smaller so lose preload

a wheel bearing is also under a shitload more axial load than your average pinion, hence why they wear fast, are you saying a solid spacer between them would make them last longer with big wheels?

see once again, your wrong but you still babble on, are all your vic club mates going to come over with some oo my mate said in theory something should happen stories again?

[acc1]

Someone trying to turn up the temperature in this thread..

[Gwagensteve]

I'm not really sure how where I am and who I wheel with are relevant. I guess we're just have to going to disagree Royce, It's clearly not going to be resolved, particularly if you're going to start taunts.

My experience, and the advice of the driveline people I work with is clearly opposite to yours.

I'm satisfied that solid spacers improve the durability of standard sierra diffs under the conditions we're using them.

I could "babble on" but there's clearly no point.

Steve.

[tanshi]

There are differences of opinion here but there is also an opportunity for good tech. If people want to find out for them selves. Thus the question above re toyota solid spacers. If nothing else being able to change seals when they die more easily would be a distinct advantage.