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Discussion Starter #1
After my recent rebuild I added 100 ml of molykote antifriction additive to the gearbox.

I thought 100ml wouldn't make much difference to the level so I didn't check it.
When in 3rd and especially 5th gear I can hear a kind of swirling noise. Possibly due to too much liquid in the box and when in these 2 gears it is frothing up the oil??

Changes are very smooth with the molykote, but in 5th it sounds like compressed air leaking!

I will check the level this week if I get time.
 

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Discussion Starter #3
well that's where I went wrong. I tilted the box while it was out of the car to put the additive in.
:rolleyes:
 

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Discussion Starter #5
Yes I will take out the plug to drain it.

Just curious of what the symptoms would be if it is overfilled.
The hissing/swirling noise in 3rd/5th gear?
 

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Don't think overfilling is an issue...

Hi Brit01,

I don't think a slight overfill is an issue, especially as one "trick" local Alfa dealership mechanics used to do when 'Suds were new was to substantially overfill the gearbox to muffle the characteristic rattle when the gearbox was in neutral :eek::eek::eek:.

Mind you, this was only done when owners complained :rolleyes::rolleyes::rolleyes:.

Cheers,

Andrew Matusiewicz
1971 Alfa Spider 1750 Veloce
1983 Alfasud Ti QV
 

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Discussion Starter #7
The additive has worked nicely. Smooth gear changes definitely.

Or maybe I can hear a noise that was there before because I haven't got the gearstick gaitor on!!
Just the rubber lower one on. Maybe the sound is more evident now!:lol:

I will put the gaitor back on and see.
 

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Discussion Starter #9 (Edited)
I had this noise in a 1.5 33, like a shhhhhh noise in 5th. I assumed it was bearing noise.
yes a shhhhhh noise in 5th. Shift down into 4th at the same speed but higher revs and no noise.

What was it?

Maybe I should whip out the oil with this additive and put new oil in. But first just check the level.
maybe 3 and 5 are lower in the oil and in too much.
I will jump off a building if the box is dying now as I've just done the engine.
 

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yes a shhhhhh noise in 5th. Shift down into 4th at the same speed but higher revs and no noise.

What was it?

Maybe I should whip out the oil with this additive and put new oil in. But first just check the level.
maybe 3 and 5 are lower in the oil and in too much.
I will jump off a building if the box is dying now as I've just done the engine.
Don't Jump Brit!!!
If the noise gets too bad - You could try turning the radio up a bit more......:lol:
 

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Discussion Starter #14
If the noise gets too bad - You could try turning the radio up a bit more......
:lol: you've used that advice before!! No radio at the moment so an alternative is necessary!:cheese:

Well back to the question.

Are you guys using GL-4 or GL-5? Mineral or what?
 

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Discussion Starter #17
Thanks ad.

says in the doc:

STANDARDS API GL4 and GL5 / MIL-L-2105D
Suitable for any type of seal and yellow material used in gearboxes design.
well I'm going to buy Motul engine oil this week so I'll see if they have the bo oil also.
 

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Discussion Starter #18
Thanks ad.

says in the doc:

STANDARDS API GL4 and GL5 / MIL-L-2105D
Suitable for any type of seal and yellow material used in gearboxes design.
well I'm going to buy Motul engine oil this week so I'll see if they have the bo oil also.
 

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Must use a GL5 oil in any box with hypoid drive. It contains the extreme pressure additives essential with the bevel/crownwheel set up. GL4 is for gearboxes and non-hypoid final drives.
 

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Discussion Starter #20
Will be buying the Motul Gear Box which is GL5 and suitable.

Also had another discussionn about the noise just in 3rd and 5th gears.
Could be some pressure on the bushing just next to the box shaft.

I modified the small bushings around the stick to make it more precise and with less play.
Could be a factor maybe.
 
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