Description

The MT82 6 speed gearbox fitted to the 2.2 and 2.4 TDCi is prone to the spline on the rear output shaft wearing which causes a total loss of drive, this spline ‘frets’ as it is dry in the same way the earlier LT77 and R380 mainshaft splines wear in the transfer case input gear, same thing, different spline.

The MT82 mainshaft comes out of the gearbox and a female/female coupling shaft (LR030054) is fitted to this with a large bolt.

A male/male coupling shaft (TUD500020) then fits into the LR030054 and the other end goes into the transfer case input gear.

The spline that wears is the one at the rear of LR030054 and the front of TUD500020.

We have devised a method to make this splined interface wet with oil which stops the wear.

We make a new coupling (like LR030054) and spark erode two small slits in the front face where it fits to a bearing, also loose two teeth from the front spline at 180 degrees to eachother (to let the oil through), then spark erode another two small slits on the rear face under the clamping bolt, this now allows oil to ‘leak’ out of the mainbox to this spline. We then machine a thread on the outside diameter and also make two O ring grooves.

The new shaft (like TUD500020) has a ground diameter that the transfer case input seals runs on, we machine this diameter further up towards the gearbox for the O rings below) to seal on.

We then make an alloy new part which slides over the shaft, this has 2 ‘O’ rings fitted to the inner diameter which seal on the new ground diameter of the shaft and has both a diameter to seal on the outer coupling O rings and a thread to fit it to the coupling.

A tube spanner is supplied to fit this part.

We are well aware you now have other options from a couple of suppliers to address this output shaft wear issue, my thoughts :

The reason the spline wears is due to excessive misalignment between the MT82 output shaft and the LT230 input gear, this misalignment varies due to the accumulation of tolerances which explains why some cars see regular failures and some dont seen to wear at all. This misalignment causes dry splines faces to rub together under load with each revolution, hence the dry dusty, rusty residue thats visable when inspecting a failure,

Its very hard (if not impossible) to try to correct this misalignment so our design doesnt fight this, it just lubricates the spline to stop the wear, this design is well proven now and we have not had one fail after about 2000 sets sold.

The other options available adopt a different approach, they replace the shaft with a solid item, I cant help but think this would just transfer the stresses from the misalignment to other components possible causing premature wear elsewhere. It just doesnt seem the correct engineering approach to my mind but its your decision !!