Whine at 50mph , gearbox?

[stemon]

Hi all Has anyone else had a whine at 50 mph on a 1.3 IQ?  it happens if i sit at 50mph but any less or over 50 it goes.

Ive changed the gearbox oil.. In fact ive tried 3 gearbox oils as trials
Fuchs TITAN SINTOFLUID FE SAE 75W
Fuchs TITAN SINTOFLUID SAE 75W-80 (made gears a bit stiff as i expected)
Now on Castrol Syntrans FE 75W

If i knock it out of gear it still whines

Still does it when i fit the winter tyres so not tyres.

Wheel bearings seem smooth but cant rule them out i guess.

I'm at a loss, The cars on about 45k and ive had it since 32k, Its always whined.

Any help would be great.
Thanks

[john p williams]

Should not be drinking and driving Dan :):)

[stemon]

lol 🙂 Its the smell of the gearbox oil i cant get enough of it.

[Milky Bar Kid 1001]

Possibly internals of the gearbox could be failing eg a shaft bearing (input shaft bearing for example). I'm no gearbox expert but just suggesting.

[Antonio 2]

Hi Dan. I also had a 50mph whine on my 6 speed IQ3.

The whine would commence at about 48mph - irrespective of gear selected. The whine was noisiest at exactly 50mph. At indicated 53 mph, the whine had gone!

I thought a new replacement gearbox would be fitted, but no, apparently, the dealer could only replace individual worn parts !

I always considered a gearbox overhaul as being a transmission specialist  job rather than a normal garage job

Fortunately,the car was under Toyota warranty (with approx 35000 miles on mileometer). Firstly, my dealer replaced a worn gear shaft bearing. This didn't make any difference. The car was taken back for a 2nd time. This time the shaft end-float needed re-shimming and they ordered various shims. This repair made a marginal improvement - however it was not a proper fix.

From the very beginning, I suspected the differential - (part of the gearbox).

On the 3rd occasion, the differential bearings were renewed. Result !

I must admit though, when carrying out the 3rd test drive, the whine was very very very slight. I decided this was as good as it was going to get. However, after a couple of thousand miles, the whine is now completely non-existant.

I know that worn tyres and wheel bearings can also cause whining noises, but if your symptoms are the same as I experienced, it may be a gearbox overhaul I'm afraid. Good luck Dan.