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Not quiet. the bearing is pressed onto the pinion. The shim goes under the bearing cup in the housing on the IRS version of the diff. I used the original shim.

On the older style diffs the shim is between the between the bearing and pinion.

The guy I spoke with today recommended using a heat gun to warm the housing a bit so the bearing cup goes in easier.

Today's mission, Washing machine locked up on the weekend on the final spin cycle, 1200rpm with a full load of towels. Looks like the seal failed causing bearing failure. In this case the rear bearing cage failed, part of it folded over and locked up the bearing. Made of a hell of a racket when it locked up. Bearings look standard but that seal might be difficult to get.

According to the manufacturer that is not repairable, the only sell the whole rear section of the tub with complete bearing/hub etc.

Ah, Ok ... That's a newer style then I'm familiar with. setup is still basically the same.

Yea, Heat gun, kitchen oven whatever is handy to heat it up good and even ... You'll be surprised how much difference a couple hundred degree F will do. (Sorry don't know the C scale)

Holly cow, that's a fresh clean break, it just snapped! Bet that made y'all jump ...

Looks like I'm finally getting a bit of good luck. Managed to track down a supplier who has these special seals. Will fit some decent bearings to replace the cheap chinese ones that were in there.

After changing the ppk value in the dash do I need to change any other settings to get the fuel calculations correct for the diff ratio change?

Looks like my bearings and seal for the washing machine are stuff in the backlog of parcels in the greater Auckland region and washing is piling up fast

Fuel economy went up the shit with the 3.73 gears even though you seem to use less throttle? Started playing with the tune and been slowly adding in timing down low which it seems to like and fuel economy is improving.

Have new shims coming to adjust the diff pinion height. Taking ages to get shit from the US as no one here seems to have a ready supply of parts here.

Washing machine back up and running but looks like the belt took a hit and is slipping. turns out it's a special belt only made for this manufacturer and it's NLA..... Closest generic belt is 4mm shorter but there is not adjustment for tension.

Mechanical and pumping losses go up with rpm and also parasitic losses from the SC running faster all adds to the losses. Economy will get worse with higher diff ratios, the exception is big cam engines can improve with higher diffs due to getting worse economy at low speeds compared to medium speeds.

I've always had better economy at speeds where you get speeding tickets. It was really happy cruising over 2000rpm. The diff change was supposed to bring the legal road speed and happy cruise rpm together. With the tune tweaks it seems to be responding. I'll see how it goes over the next couple of tanks of gas and see where things settle.

It is more engine rpm but you gain mechanical advantage due to the shorter gears. It's about finding the right trade off, 3.46 gears are probably ideal but wanted to try the 3.73 gears for the greater fun factor. I'm running a 3.2" pulley and 5% OD balancer so mechanical/pumping losses are probably far above the factory engine regardless.

Understand that engines efficiency changes at different rpms load points etc. My one tonner is getting better economy with 3.27 gears over the 3.08.
But isn’t there some maths behind this that affects the outcome? Say the injector rate is 1.000 at 1800 rpm at 300 MGC at 100km/hr, would you have to be below 0.750 injector rate at 2400 rpm at whatever MGC point on the table you are at now to be using less fuel for the same road speed? Or is it not that simple? Will spark timing or other changes get you below that point? Interested to see the outcome.

I'm not sure if there is a mathematical solution. Injector rate doesn't mean much because you are using the injector rate to fine tune the MAF curve. I've used 3.45's before and got better economy so this time I wanted to try the 3.73's. Just having to work a bit harder for it it seems.

Shorter gears allow the engine to accelerate faster. A engine that accelerates faster can generally handle more timing. The engine is effectively under less load so should be a little less sensitive to extra timing.

All the map ecus use less with gears maf uses more cause the maf sees the extra flow of air from the extra rpm my vx loves to labour in 4th instant fuel usage is low click it back to 3rd usage skyrockets all my old vn and vp got driven in 3rd unless you hit the open road and would use less gas