Gearbox angles vs oil level

[Retrohowla]

It has been suggested to me that the slightly ass down angle my gearbox is running at might be the cause of its catastrophic failure the other day.
Its a 1994 DI and MT75 in a MK 2, the unit seems to sit high at front low at back.
I'm wondering if this has any bearing on the oil level and if its getting oil up to the input shaft bearing etc?
Any MT75 experts out there?

[loot]

Is it correctly installed as per manufacturer spec?

[Mr RVM]

How slight is "slightly lower at the back" I would have thought it could cope with an inch but 2 inches or more would potentially cause the front bearings to be starved of lubrication as it relies on the gears to pick up the oil from the bottom and fling it up to the top

the correct oil level with the box at "Design" level should mean the input shaft bearing will be submerged in the oil (even when stationary ticking over) but if the box is tilted too far back then it could be running "Dry"

Cant the rear of the box be brought up by altering the crossmember or packing up the mount

[Retrohowla]

Cheers guys, I wonder if anyone could measure the distance from lowest point of bell housing to the road and flange coupling to the road? Then I could determine if my installation is causing the issue or not.
Anyone with a standard MK4/5 able to do that?

[MinorMatt]

I will try this evening (on an unloaded 150 lwb)

[Retrohowla]

Spot on cheers Matt

[Retrohowla]

Would anyone have a chance to do some measurements this weekend at all? Would be very greatful indeed

[MinorMatt]

I forgot... it was a bit busy when I got home on friday

I will make sure I get some for you tomorrow

[Retrohowla]

Yep no worries thank you, i realise everyone has busy lives, just whenever you get chance mate, thank you

[vanfox]

Locate the filler plug and hold a short spirit level against it. Look along it and visualize the level of the oil looking forwards. Compare this to where the input shaft is in the box, ( OK, it's a guess but you should get a good idea from the casting marks on the casing). I doubt whether the level will be lower than bottom half of the bearing but if you're worried add a small quantity of oil through the gear lever hole, again this will be a guess, the box holds 1.25 litres so 250 to 500 mils should be enough.

I don't believe the slight angle would cause any probs, it's just like going up a long steep hill. The gears will throw up enough oil to keep the box lubricated and oil will settle in the front bearing outer race when stationary.

[MinorMatt]

My van has the plastic shround still around the gearbox... so dims are approx.

Bottom of bellhousing to ground 12.5", underside of rear mount (i.e. top surface of mount) 15"

Hope that helps?

[Retrohowla]

Thanks for the advice guys, much appreciated
I will do the spirit level thing as soon as I can find my spirit level lol.
Matt, just to confirm, you measured from the bottom of bell housing flange, the most forward point and back mount where aluminium box meets steel mount yes?
If so mines not a million miles out.
12.5 inches front and 14.25 rear. Obviously the roads not perfectly level but it doesn't seem too far out from standard.

[MinorMatt]

my bellhousing is covered in the plastic shield, and the flange is above the crossmember. But the measurement given is approx from the lowest point of the flange to the ground.

The other measurement is to the interface between the gearbox and rear mount.#

I wouldn't be concerned about the dims you have given there

[Retrohowla]

Thats great, thanks for that Matt, much appreciated.
Its looking like i just had a bad box and the installation is fine, just dont want it happening again so thought i better check.
Thanks again chaps