I'm parking this here because all the top Aussies seem to visit
this section.

Almost all manufacturers of differential gear sets mention that
their products are "lapped" as matched sets at the factory.

Presumably, this is applies to gear sets supplied world wide.

However, it seems that there is a service that is particular
to Australia. There seem to be a number of firms offering
differential gear lapping of used gears to the the public.

One well known firm seems to be:

Diff Lapping Brisbane - differential repairs Queensland, PNG

In North America, the practice is to observe the mesh pattern
before disassembly, then try to reproduce it on reassembly
when the gears are reused.

No mention of gear lapping.

So what's going on there?


Other things denied to North America:

Utes and coil spring rebuilding

You can keep the killer spiders

 

If you like utes , you may enjoy this. Would have been better if he did it with a bale of hay and a blue heeler in the tray, but very tidy regardless :-)

 

We Aussies are very different, and WE know it.

That gear lapping has been around as long as I can remembr. We once had Adelaide Spiral Gear, but they seem to have gone AWOL.

The OLD steering boxes were a favourite for "lapping" to rid them of high spots.

Spring makers, yep, we had many, but sadly the last one closed its doors at the end of April 2016. Now we get replacements form C&**a, bugga.

Killer spiders, awesome on the flame thrower, they POP nicely. Its the King Browns ya gotta look out for.

 

As long as you can remember?

That would make it since the dawn of mankind then?

So, now I revert to child mode ... (wishful thinking HA!)

But WHY does diff lapping happen in your neck of the
woods and seemingly nowhere else?

It seems like a sensible thing that has perhaps gone
the way of the dodo bird elsewhere.

 

We still make springs in Australia!

 

HA, it feels that way today, damn I forgot how much pain the cold weather gives me, must migrate to the Tropics maybe.

I dont have a definate answer, but back in those days, Crown Wheel and Pinion sets, were both hard to get, AND expensive. Most of the "noise" was directly related to incorrect pinion settings, so a "lap job", NO, not a lap dance (I wish), mostly sorted them, and for pocket money by comparison.

I had both the diffs on my Road Train done at 400000kms, and that shut them up 100%, and at that time Diff gears were many thousands of dollars, and Ex Germany, and this was the "standard" fix at that time.

Not sure of the situation now with most vehicles being "throw away".

Example, the daughters XJ40 had a "singing diff". so I fitted a replacement from a wreckers, at a $150, all done. Trashed the old one, simply not worth the effort/cost to rebuild it.

 

I was thinking of downtown Adelaide.

Coils, I use King if Genuine are NLA, but my OLD brain was thinking Leaf Springs, and the resetting process that plagued them.

Industrial Engineers and Spring Makers did all that, included coils, and the quality was awesome.

 

We still have a good leaf spring maker in Brisbane, I have used them many times over the last 20 or so years to have an extra leaf made, fitted & reset for my less than adequate driveway.
Can't remember how many cars I've had to raise the rear an inch or so to get into my garage.

 

I'm not ignoring you

Can't do youtube on this computer.

 

Leaf springs are no problem here.

It's retempering coils that seems to be unavailable here.

And since this is now heavily oriented to Australian members,
I'll link to a nice 40 page booklet from Penrite:

http://www.penriteoil.com.au/tech_pd...%20GREASES.pdf

 

USA views:


1. Eaton spring company in Eaton, PA. leaf springs to spec's. Son refitted his 64 Chrysler 300K with pair.
Might also be a source for coils. Racers use them in various heights
and loads. Balance cars that way.
2. Mordrop in Oakland, Ca. A blacksmith shop primarily. Gained fame
in early days by changing the shape of beam axles to lower transverse springs. Also reworked leafs springs. Eyes on the front and rear springs of my forties hot rod. Lowers the car.


3. Lapping a ring gear and pinion or marking it to determine pinion to
ring gear mesh and guide the correction. Lapping denotes grinding?.
News here. That is tough metal...


Carl

 

I'll ask the rep next time I see him, but i doubt they have "printed books' anymore.

Even the Lube Guide we once had hanging on the oil rack has been replaced with a "tablet" lookup.

Better, more frequent "updating ability" is the reason given, and I have to agree.

 

Fair Dinkum, I told ya I was OLD.

I read that as "I like a...........", when in fact you typed "link to.........".

Maaaaaaate I need a coffee.

 

That's ok. Because of the neighbourhood there have been a couple
of posts where OLD was on the screen and I read QLD.

On a 27" screen at that!

Just came back from probing the part load breather.

Decided the MAF and TB can wait until tomorrow night
when the car can be down. Groceries first.

 

The standard machine is a Gleason. Or at least it was.

I know about marking and shimming, but apparently
"down there", they've been standing on their heads
out in the sun a bit.

NOT that I object to the concept. I think it's wonderful.

But being off vehicle on a machine, once the lapping
is done, it is still precision work to mount the gears.

There are a very few shops in North America that do
it as custom work on new gears for racing applications.
But, it is not a routine procedure for used gears.

 

Plums:


Thanks. learned something. That is always good!!


Carl

 

!!

when England was doing its ethnic cleansing, it sent all the GOOD Genes and DNA to OZ.
and also to the colonies,(USA). LOL.

 

But at least the Aussies did not feel the need to
create new standards for threaded devices.

Top of mind right now because the diff breather job
got interrupted last night due to the thread being
1/8" BSPT. I ordered 1/8" BSPP from the UK.

In Australia, you go to any parts place and get
one for a buck. At worst, you go to Pirtek.

On a brighter note, having confirmed the exact
thread, suitable parts can be ordered from Toyota.

The funny thing is that all the US 4x4 sites insist
that the reason that 1/8" NPT does not fit is that
it is METRIC! All the articles point at one of three
part numbers from Toyota or Nissan. But, only a
few know the parts are BSPT. Then the others all
pile on and keep on referring to the parts as METRIC
ignoring the one poster who has told them it is
BSPT.

The OZ 4x4 sites all correctly identify the thread
as BSPT.

Lots of peering at pictures to finally figure out that
the parts are indeed BSPT.

 

Told ya we're a special breed, and PROUD of it, HA.