On Dec 8, 4:49*pm, "Doctor Drivel" wrote:
"js.b1" wrote in message

...
On Dec 6, 5:34 pm, "Doctor Drivel" wrote:

One automotive engineer, not mechanic, said the best thing is use the
likes
of Mobil 1 oil and a high quality oil filter that grabs particals of
smaller

Actually since about 2004 Mobil 1 is no longer a true fully synthetic.
.

I think gear oil is neglected especially as it lubricates the diff and drive
shafts as well. *How sensitive is gear oil to extended changes? *Is fully
synthetic gear oil superior. I would assume so as it would take more to
break it down.

Garages will top up via the vent plug so overfilling the box. Can't
remember the details, but the oil wont work as required when the box
is overfilled like this. It's better to have low oil than an
overfilled box. Next time I'll be using a molybdenum disulphide
loaded oil, probably a Rocol product. There's no need just now, needs
a few years (probably 4) and miles before the standard gearbox oil
starts showing effects of deterioration. The extreme pressure
additive in a standard gear oil is not particularly hard wearing.