hi,

i've noticed a quiet whine (engine speed related) under decelleration recently and am looking for suggestions. my current guess is gearbox/diff beginning to fail but could it just be low on oil. i had thought it has a sealed for life unit but there should be a drain plug no?

other sources i've thought of include the aux belt (replaced 1000 miles ago), cambelt? never heard of one that whines but the noise is engine speed related. alternator bearings? the unit is a recon (only 1000 miles old now...) the air-con wasn't on so i've ruled that out. i've also move the fan through its speed settings on all the options and i don't thing its something stuck in the vents. the noise is the same with re-circ on or off.

i've revved it up on the drive and listened but couldn't hear anything hence my gearbox thought.

what sort of gearbox oil does a vw 'box use? 80w90? or might i need something clever from vw. and lastly if there is a drain plug is it mounted horizontally so you can add more oil should you want to?

edit: its a DUU gearbox mated to a AKL 1.6 engine. i've had a look at there aren't 2x17mm bolts for drain/fill as VRS posts on the same subject. there is a small torx (5mm maybe) on the bottom. is this the drain and do i fill through the speedo hole?

any help appreciated.

toby

Edited 16 March, 201016 yr by toby

after some more looking the trx plug on the underside i'm sure is the drain but i can only guess the speedo hole doubles as the filler.

the questions are then how much oil goes in the box and is there anything that falls off the speedo unit if i'm not careful?

i'll procure 3l of vw 75w90 oil (as required) tomorrow possible and some tools as the TRX plug looks to be more like a 50 or 60.

lastly does excess oil escape from the breather if i just fill up to the speedo hole?

any input appreciated,

cheers

The DUU transmission is an 02K variant.

The filler plug is on the LHS of the box next to the driveshaft.

Capacity is 1.6l and I suggest you get the gearbox oil from the VAG dealer as some gearbox oils seem to cause a notchy gearchange.

On the VRs the filler is on the front of the gearbox, cant remember what size it is but its a hex key, jumbo :-) , available in a set from Halfrauds by Lazer tools, cheap as you like. Running lightened flywheel so jacked mine up to give it a bit extra fluid :-) tis a bit quieter now. Used a syringe for mine as didnt have any hose to run down to it so worked from underneath with some trusty shooting at the hole.: LMFAO

well after some crawling in the mud under the car i've found both 17mm hex bolts as all the other posts suggested. waiting on local vw place to get in 2l of gearbox oil. only needs 1.6 litres so i can lose a little.

i'm not sure how to encourage the oil in - i'd rather not syringe it in 10ml at a time (only syringe i have) - i think possibly a tube pushed up through the engine bay attached to a funnel might work.

thanks for all pointers,

regards

replaced the oil which was foul with new VW stuff (almost clear). two tiny fleks of metal in the old oil that i take to be casing swarf rather than gear teeth. sadly the noise hasn't gone away but i did notice a small tear in the oil breather pipe going into the throttle body so that'll need fixing.

any thoughts on a road speed dependant quiet whine only present when the car is nicely warmed up mostly noticable as the car decellerates but its slightly audible under acceleration. doesn't appear related to engine speed at all. everything appears to work as normal.

thanks rwbaldwin for pointer. it was there just hidden under muck.