Noisy 5th gear

94 300 Tdi manual. 5th gear has recently become very noisy when under power at above about 55mph. All other gears are quiet and the box is smooth, I have 3 litres of atf in the shed to go in it. but I have the feeling that that wont make much difference, as it would appear to be worn bearings on 5th , and as Im not an expert on gearboxes, your thoughts would be appreciated. 127.000 on the clock.

Difflock sell synthetic oil for gearboxes.
May be worth a try before condemming g/box.
Solved the 1st - 2nd gear slippage on my 300tdi (182k)

ANDYKNOWS said:

94 300 Tdi manual. 5th gear has recently become very noisy when under power at above about 55mph. All other gears are quiet and the box is smooth, I have 3 litres of atf in the shed to go in it. but I have the feeling that that wont make much difference, as it would appear to be worn bearings on 5th , and as Im not an expert on gearboxes, your thoughts would be appreciated. 127.000 on the clock.

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Before you decide to chuck the box away, why not try an oil change in the box, it's easy enough to do and it might work.

I would reccomend trying Difflock oils also, I put EVO1 in my wifes Tdi200 and it's loads quieter and smoother now - it's not cheap but it DOES seem to make a difference.

Putting the atf in that you have already MIGHT improve it, but if I were in your shoes I would try EVO1.

Follow the link: 4x4 Store

Hope that helps,

Dave

Have to be atf and molyslip additive for now.

Changed the oil today, took 2 of us 15 minutes to get the drain plug off, ended up getting an adjustable spanner on it and then a trolley jack to lift the spanner from underneath, it was so tight. Nice clean oil was then drained from the box. Think it was last changed about 2 years ago. Was very tempted to put some ep 80/90 in it. anyono know why its not used, It goes in the transfer box, so why not the gearbox?

ANDYKNOWS said:

Changed the oil today, took 2 of us 15 minutes to get the drain plug off, ended up getting an adjustable spanner on it and then a trolley jack to lift the spanner from underneath, it was so tight. Nice clean oil was then drained from the box. Think it was last changed about 2 years ago. Was very tempted to put some ep 80/90 in it. anyono know why its not used, It goes in the transfer box, so why not the gearbox?

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It's much too thick, if you use it you'll ruin the gearbox.
Cheers
Dave