draining the gearbox oil from the diff

[xpress]

hi there. do you drain a gearbox with the rear drain plug on the diff.

clonking juststarted at the rear.

many thanks and salutations.

[croc]

The drain plug is on the bottom of the gearbox case with a 17mm hex 'socket', requires a hexagon key.
MAKE SURE you can remove the FILL plug before you drain - this can be very tight. Same hex key needed. Near the gearshift input shaft.

'Clonking' may be CV joint on drive shafts, also check rubber boots while you're there.
Also, the 6 bolts, each side, attaching shafts to gearbox flanges - these can work loose but the rubber boot stops them falling out completely.

[xpress]

could it take some time for the oil change to go to the cv joints and is there a filler for the diff and gearbox or are there separate drain plugs for both?

[bigherb]

The CV joints are not lubricated by the gearbox oil they are grease filled with moly grease.
The gearbox and diff share the same oil unless it is an automatic which uses it's own gearbox oil. Manual gearboxes it is drained from the plug on the rear of the diff and filled at the gearbox filler plug near the gear lever linkage.

[faggie]

better of draining the gearbox oil after a long run as the oil will be thinner and the gearbox case will be warm

[ghost123uk]

'Clonking' may be CV joint on drive shafts,
Also, the 6 bolts, each side, attaching shafts to gearbox flanges - these can work loose

Yep, check the drive shaft flange bolts, both ends, both sides = often a cause of clunking.

Changing gearbox / diff oil whilst a good thing to do, will not cure any clunking.

[xpress]

happened after changing oil. maybe it was oil working its way into the half shafts.

[xpress]

its stopped now soundedlike horses Hooves. sped up the faster you went.

[xpress]

'Clonking' may be CV joint on drive shafts,
Also, the 6 bolts, each side, attaching shafts to gearbox flanges - these can work loose

could this be a reason for a wheezy whine when changing from first to second I wonder? and difficulty changing gear?

[kevtherev]

Nothing to do with it

[xpress]

ghost could you give me a description of where these nuts are on the flanges? and where i will be likey to find them? also what size socket and tools i will need and i will go and tackle it. thanks.

today the clonking started again always going up the hill, i presume where it gets the most load along with the weight of the stuff in the van, i am still getting trouble getting in gear and a bit of a whine when changing gear and using the clutch pedal. clutch on way out? maybe linkages out slightly.

[lloydy]

if you go under the van and find the driveshaft, you will see that either end is bolted to either the gearbox or the wheel. Six bolts each end, they will be hex head or spline. Spend a bit of time cleaning the heads of the bolts out, as this will make it easier to undo/tighten, and less likely to round one off. Check the drive shaft too, in out movement is ok, side to side/up and down movement not. Jack up rear of van and turn wheels whilst checking driveshaft for odd notchy movement.
It's quite an easy job to remove the driveshafts, you can then clean and grease them up again, and check for wear on CV jointsj and maybe fit new boots. Quite a satisfying job