Diff?Gearbox? wineing under engine breaking

[terrano]

Im trying to work out what would be causing a loud wining noise under engine breaking, it doesnt do it any other time other than when engine breaking. It is very loud and seems to be coming from gearbox, but i was thinking maybe front diff? Is there anyway of telling? Apparantly gearbox has been rebuild but no receipts to prove this.

[Crash bandicoot]

1 thrust bearing in gearbox shaft.

2 worn pinion shaft bearings in diff as the opposing load is placed on the pinion shaft with its helical cut teeth it will force the shaft to move opposite to what it normally would. if the rollers in the bearings are worn they will be noisy under this situation.

also why alot of vehicles drive trains are quite noisy when reversing.

[terrano]

Ok cheers, the old owner of the vehicle said who ever rebuilt the gearbox put the old thrust bearing back in by mistake, which is why he said it wined, but i wasnt quite shore, so sounds like he may be right. Is this a hard one to replace?

[Crash bandicoot]

Ok cheers, the old owner of the vehicle said who ever rebuilt the gearbox put the old thrust bearing back in by mistake, which is why he said it wined, but i wasnt quite shore, so sounds like he may be right. Is this a hard one to replace?

on the money