Thread: Tdi 300 1996

Do your Tailshafts have the Rubber Do-nuts instead of Uni-Joints, if so check to see if they are buggered, or the Ball Joint on top of the rear diff, Regards Frank.

Or, worse case scenario, but very likely, worn splines in the t/case input gear and the gearbox output shaft.

I don't know when the cross drilled input gear fix came out. Someone here may know if the 96 model was fitted with the cross drilled gear.

Replacing the input gear is reasonably easy, but a new gearbox mainshaft is $$$.

You can inspect the splines:

Remove the circular PTO cover at the rear of the t/case.

If you see a fair bit of red oxide (like rust) mixed with gunk, then you have worn splines.

The red oxide is the result of the process called fretting corrosion, which occurs when you have relative movement between steel surfaces (the flanks of the spline in this case, but also common between bearing inner rings and shafts). The problem is lack of lubrication, which the cross drilled gear addresses.

To be sure, pull the input gear from the gearbox output shaft to inspect the splines.

You may have to put the gearbox and t/case in neutral, and rotate the input gear until the teeth line up with the tooth space in the intermediate gear that the input gear has to pass by as it is removed. This should make more sense when you are looking inside the t/case.

If you don't have the cross drilled input gear, the splines wear until you loose all drive (forward and reverse).

what he said!

Maybe she's just rough.

Originally Posted by clean32

<snip>
Or is it just because she learnt to drive in Volga’s and t34s

Originally Posted by Dougal

Maybe she's just rough.

ok cool, do you have an exspanded drawing for this, before i dive in??
i asume thats the spline in the back ground?

Originally Posted by Bush65

Or, worse case scenario, but very likely, worn splines in the t/case input gear and the gearbox output shaft.

I don't know when the cross drilled input gear fix came out. Someone here may know if the 96 model was fitted with the cross drilled gear.

Replacing the input gear is reasonably easy, but a new gearbox mainshaft is $$$.

You can inspect the splines:

Remove the circular PTO cover at the rear of the t/case.

If you see a fair bit of red oxide (like rust) mixed with gunk, then you have worn splines.

The red oxide is the result of the process called fretting corrosion, which occurs when you have relative movement between steel surfaces (the flanks of the spline in this case, but also common between bearing inner rings and shafts). The problem is lack of lubrication, which the cross drilled gear addresses.

To be sure, pull the input gear from the gearbox output shaft to inspect the splines.

You may have to put the gearbox and t/case in neutral, and rotate the input gear until the teeth line up with the tooth space in the intermediate gear that the input gear has to pass by as it is removed. This should make more sense when you are looking inside the t/case.

If you don't have the cross drilled input gear, the splines wear until you loose all drive (forward and reverse).

Could also be the clutch plate what a silly design they are, The spline in the standard ones is supported with springs when the springs let go you end up with free play with in the spline of the clutch