Whine in first gear and reverse

[Barry flint]

Any help my 1.6tdi has started to whine for a brief second or 2 when taking of in first gear it also has the same whine in reverse but doesn't do it all the time,
Any body had this issue before, im suspecting gear box, as not sure if I have smf or dmf

[STP]

Don't think the 1.6 has a dmf. Only the 2.0.

Might be worth doing a gearbox oil change. Been thinking about this myself, as the gears are way smoother in really cold mornings with the oil thicker, than they are when warmed up. Gets notchy when hot, if selecting first when sitting at junctions.

If it was a gearbox bearing, surely it would whine all the time unless the engine noise is covering it up at higher speeds.

[Barry flint]

Yeah i was wondering why it only whines for a couple seconds only in first gear and reverse,
But doesn't do it all the time,
Strange one,
I will definitely look in to changing the oil as not sure it has been done in past certainly wont do any harm, its only got 80k with full service history,
I did discover there last week that the 1.6tdi is a solid mass flywheel,
I was also wondering it is currently lowered and stage 1 remap, could the whine potentially be the inner drive shaft cv joint? Im pretty sure I read somewhere that with it lowered it can change the geometry of the driveshaft and with the extra horses it could potentially lead to premature wear on the inner cv ?

[STP]

CV joints tend to make a clattering sound when they wear, not so much a whine, maybe the diff output bearings if it's lowered. There has to be bearings on the outputs of the diff casing for the driveshaft flanges. Maybe get the front jacked up and onto axle stands under the front subframe, then you can run it in gear and have a look underneath and a listen, to see where the noise is coming from.

[Barry flint]

Stp will this still produce a noice when jacked up at front end? I will certainly try this as struggling to pinpoint what this could be the weird this is it doesn't happen all the time, if thats the case does this rule out the gear box?
It has whined in 1st gear reverse gear and a faint whine in 2nd gear and its always intermittent,

[Barry flint]

Also can these bearing be replaced if this is the issue?
Without dismantling gearbox

[STP]

Lift it on axle stands and run it in gear, it's very possible it will still make the noise and you may be able to pinpoint it.

However...

None of the bearings mentioned can be easily replaced I'm afraid, as far as I know. Any issue with a gearbox bearing or a diff bearing would be major removal and rebuild. The days of coned roller bearings are long gone and everything is friction fit and pressed in with a lot of force. Not to mention the gearbox bearings have shafts running through them.

I would maybe try getting the gearbox oil drained and replaced, it's likely the diff shares the same oil.

If this doesn't cure it then the other options involve a fair bit of labour and replacing parts. I'd rather swap to a used gearbox than tear the existing one down to replace bearings.

Take the simplest routes first, always.

And remember, a slightly noisy bearing will last a long long time before failing. Most of the wear has already happened. If the noise is slight and bearable, it's not a show stopper.

My advice, if it was mine, drop the gearbox oil and replace with fresh. See what it does.

[Barry flint]

Many thanks stp
For your information
Yeah its probably best to dump oil first now you say this and have fingers crossed lol.
Failing this i will certainly look into either a good used or reconditioned box,
Is it a case of getting a specific one for the 1.6tdi is there different variations?
Once again cheers bud

[STP]

Ah I reckon to use the standard gearbox is best. You can swap to the 6 speed but the driveshafts are different as far as I know.

Try the oil change first, it's cheap and you may be surprised!

If not, come back and we can investigate what's possible.

[Barry flint]

Hi me again
Dumped oil from gear box removed about 1.3 litres
And put 1.3 litres back in. Removed lower hex nut,
,I was just wondering is there not more oil capacity in these boxes maybe 1.7 or 2.2?
Is there a way to release all the oil?
I had the air box out checking for anyway to release more oil
After this took for a test drive and whine noise has gone maybe dirty oil ?
But id like to think its a full oil change rather than a mixture of old and new

[STP]

Not sure about the draining of all the oil, maybe it isn't possible but some transmissions have a separate drain plug and fill plug. Anyway good to hear it solves the issue and I don't think a wee drop old oil will do any harm at all. Good result.