Hilux 4x4 Forum

Pulling the filler plugs off the gearbox and transfer case of my 1995 (G52 gearbox and standard transfer box) I note that the oil pours out the transfer filler (about 200ml) and nothing out the gearbox filler (can't reach the oil when I stick my finger in). The truck is on a level surface with the nose about 50mm too low due to sagged leaves (OMEmu - how may I fix this??). I take it that the gearbox/transfer interface seal has given up?
Probably will only get around to pulling the box out in 2-3 years to replace the clutch and may set the car level before that by re-tensioning the front springs.

Will this be a train-smash if I refill both boxes to their correct levels and let them slowly equalize out?

No train smash, but not ideal. The head-space of air is there to take up some of the expansion when the boxes heat up .... if they were filled to the brim, oil would be forced out with heat expansion. The X-fer box is already full (overflowing you said), so just fill the gearbox. Fill till it runs out at the filler plug and close it up. If the seal is indeed leaking between the two boxes, expanding oil from the X-fer box will be forced back into the gearbox. We're really only talking about a small amount of oil here.
The gearbox will vent through the lever turret.

Do the seals right through when you're ready.

Ah so the boxes don't actually have designated breathers then - thanks for the peace of mind Mud Dog.

To fix the sag: http://www.hilux4x4.co.za/strengthen-hi ... /index.php

No breathers on the gearbox or transfer

Thanks Nic, it is actually the re-tempering/tensioning of the leaves I am looking at. I'm not sure whether to go hot or cold and which will last longer. My truck has had the saddles done and strengthened already, probably when they installed the OME leaves..

Don't do the heat treatment, you will be sorry!!

All suspensions will sag a bit as they settle down and personally I would leave it be unless it's really bad. I had OME fitted to my first van and after the initial settling of about 20mm they settled no further even after some serious abuse.

The most common cause of the front sag is the spring pedestals (saddles) collapsing on the outer edges, but you say that this has already been done. The other thing could be the weight in the front - do you have a motor conversion (heavier motor than standard), do you have a winch fitted or do you have an integrated bull-bar / bumper fitted that's heavier than standard?

If you have additional weight in the front, then have an extra blade fitted to the front leaf packs (the heavy duty option).
If not and you're going to do something to the springs, rather do the cold press reshaping. I had a sag in front on one side with Dobinson's suspension about 4 yrs ago and sorted it that way .... still good today and I've done some rough stuff with it over those years. I did a post with pics about it .... will look for it and post the link here for you.

Here's that link ...... viewtopic.php?f=3&t=28052&p=331711

Thanks for the advice and the link - have bought a 10 ton jack (overkill I know, but Midas was sold out of 6's) and will weld up a small jig to go with it to cold temper the leaves.

Cool. Let us know how it goes.

OH! ...... we'll need to see pictures as well!

As a guide, would you say that to get 60mm lift from a leaf pack, I would need to bend the longest leaf to an increased arc height of 60mm and the lesser leaves to follow the new curvature?

Double it (60mm more curvature on each side). Maybe even a fraction more, it's still going to deflect quite a bit as soon as you put some weight onto it. Then you also have to think that it will settle a bit as time passes but mine is still sitting level after about 3 years since I re-shaped my leaves.

When I did the cold press re-shaping I worked on each leaf at about 200mm increments along it's length with about a 50mm overlap if I remember correctly.

Where I've written +60mm is the arc height (or sagitta to be precise) - so to get 60mm final lift are you saying that the required additional arc height is to be 60mm or should that read 120mm? (excluding any extra for settling).

The sagitta. But like I said, increase it a bit to compensate for normal deflection and possible later sagging. Perhaps more like 80mm

Look what I did here ....... viewtopic.php?f=3&t=28052&p=331721

I see that you got approx. 40mm of lift by increasing the sagitta by 180mm, so I will go for 200mm to start with as I need quite a bit more lift than 40mm (60-80mm).

The perch heights on the front axle differ by a couple of mils but I'm sure the arc heights will differ quite a bit more when removed so here's a question - does anyone know the difference in arc height of the OE LHS leaf pack to the RHS leaf pack when removed from the vehicle??
I need to get an idea of how much more to bend the LHS pack than the RHS pack so it sits level...

Are there two seals at the interface of the gearbox and the transfer case? - i.e. gearbox rear seal and transfer front seal. If so, can you replace those seals by merely splitting the two and pulling out the existing seals from the gbox rear face and tcase front face or is there a bit more to be removed?

There's just one seal: http://japan-parts.eu/toyota/gr/1995/hi ... gasket-kit

Though on mine it looks like one of the previous owners took a short cut and used gasket maker rather than a real gasket

Sorry Nic - I mean oil seals around the shafts that turn. On the pic in your link, where the shaft comes out the front of the transfer, is there a seal around that? And similar on the rear of the gearbox?

This interface:
Rear of gearbox appears to have one:
Transfer front not:
So I suppose that to split them you have to drain the transfer oil, as the edge gasket keeps it in...

Like this:

I've not had mine apart, so I speak under correction, but what I can see from the parts stackup, is that there is only the gasket on the mating faces of the t-fer and g-box, and not around the shafts themselves. There are no o-rings or lip seals in that gasket set.

It's just the casing gasket on the X-fer box side. Those roller bearings have to run in oil.