Setting up diff / measuring bearing preload

[crispy'86]

Ok so as above i'm going to reassemble my hilux diff (centre) this afternoon, have the workshop manual with the relevant pages and got the tools in my toolbox to reassemble it. Have fitted new pinion bearings to it, have the dial gauge top measure crownwheel preload etc. But my question is who out there in Toyspeed land has set up their own diff and successfully measured the pinion bearing preload. The manual states you need to check the drive pinion turning torque (bearing preload) and the total differential preload with a "low range torque meter". So does anyone have the tool to do this and measure it ?? Ideally i'd like to do this properly and not have to sacrifice my new bearings due to a huge cock-up on my part. Specs are 1.9 - 2.5 Nm for drive pinion preload and an extra 0.04 - 0.06Nm to check overall torque.

[Grrrrrrr!]

Torque = force x distance..

Lever arm of known length, bucket/cup with handle and measuring jug full of water or set of scales.

1 litre = 1kg = 9.8 N

Just make sure lever arm is horizontal when filling the jug/cup.
And with such a low torque to be measured you need to account for the weight of the arm, or make it symetrical.

[strx7]

i've just used handometer when putting diffs together, never had issues with any yet, probably done 30 or so over the past 9 or so years.

[crispy'86]

Yeah guess it's the old saying you get a "feel for it" after the first couple of times then it's all pretty easy every one you do after that. Have seen people recommend getting a dial type torque wrench so you can see the actual figure. Doubt you'd be able to get your hands on one cheap here in NZ, i just don't want to get too heavy handed if i used your method and have a ctastrophic failure.

[evil_si]

Fish scales are good, wrap string around the inut a dozen times and pull the fish scale to get a measurement

or rolling type torque wrench

[crispy'86]

Fish scales measure in kg only don't they ? haven't thought about using them because i always had the impression would be tricky to measure such a small Nm measurement

[Grrrrrrr!]

2.5kg at 100mm = 2.45N.m
25kg at 10mm = 2.45N.m
Just pick a suitable lever/pulley size.

[DVSMOTORSPORT]

Like Simon said, wrap string around it and use fish scales, unless you have a 1/4 drive tourqe wrench that you can watch while turning it. Just rememebr you want the rolling preload, not the initial preload.

[evil_si]

Yea just convert the units to what you want, grab the smallest fish scale available usually $5-10
As ben said its the rolling torque, ( the force it takes to keep it moving at a constant speed ) not the initial toque it takes to move ( sometimes this is 2-3 times what the rolling torque will be )

[crispy'86]

So i'm checking and double checking the tooth contact area before i fully assemble the diff head. Have just run the pinion nut up by hand without the crush tube etc to be on the safe side. What's the best method to do this. do i need the marking bluie like the manual says ?? I've read somewhere else it says you can use poster paint but will i need to wait till this fully dries before running the crownwheel back and forth through the crownwheel??

[evil_si]

Bearing blue jus makes it easy as it washes off and doesnt dry as such,

Ive used white spray paint in the past, have also painted the teeth white then used bearing blue to see the imprint better

If using any sort of paint, be quick and do it while its wet,

[crispy'86]

So the best tooth contact pattern seems to be dependent on the type of diff. Some state that the pattern on the toe on the drive end and heel on the coast end is the best pattern. Others say centre tooth contact on the drive and coast sides are ideal so WTF!!! Do i just risk it and fit it as is and risk having a noisy diff?

[DVSMOTORSPORT]

Out of all the diff Ive done, Ive only had to re-shim 1 pinion.