gear box/axle oil change

[morrisminor]

I'm sure this has been covered many times before but how often does everyone change their axle and gearbox oil ?

[Reckless Rat]

I've just changed mine on the RP (back axle) I last did it in the 1980s, and to be fair there was nothing wrong with the stuff that came out. The only time I've changed the gearbox oil was when I stripped and rebuilt it a few years ago (4 spd crash).

In both cases it's more important not to overfill.

[Dave Mann]

About every two years, or if there are new noises emanating from the unit. It is usually done hot otherwise it takes forever to drain.

[Chris KC]

erm..... occasionally...

It's far more important to check there is actually some oil in them now and then.

[Biddlecombe]

Well that stuff I've just scraped out of mine was probably there about 40 years.
   

[Dave Mann]

Oil level checks are done much more frequently, about every 3 months, or when I remember..

[Bob Culver]

“Modern”oils and greases have remarkable resistance to oxidation and do not turn to treacle or gel. For moderns gearboxes/diffs sometimes filled for life, like wheel bearings. For older cars with some plain bearings oil needs to be kept reasonably clean, and crash gears are inclined to produce metal (altho Seven gears seem to resist chipping better than some other makes), so very occasional changes desirable. (The frugal can pass thru a filter or allow to stand and reuse, but best not to mix diff oil!)

If oil looks like silver paint something is wearing. Can often continue for years .The life of say a pitting 1st gear is determined more by tolerable din. As mentioned, maintaining the (low) level is vital; many today are unaccustomed to regular checks and top ups.

[Dave Mann]

I inspect the drained oil for metal particles, a bit like panning for gold, because that is the first sign of trouble. About 14 years ago we visited the Hebrides and had no sooner arrived in the islands and the diff started making it's presence heard. A local garage let me use their drainage tray and along with the oil was a load of scrap metal. I refilled the diff drove round the block drained and refilled it a couple of times until the oil was clean. Then refilled the diff and continued the holiday covering a further 500 miles with a silent diff, it was drained on arrival home to find only a few metal particles in the oil. A strip down revealed part of a crown wheel tooth missing. I don't think we'd have made it home under our own steam without those precautionary measures.

[Ruairidh Dunford]

Ahhh, the Hebrides trip!