Thread: TD6 reliability gear box

Originally Posted by BigJon

Do you think fitting a new valve body to a high mileage ( 140 000km) but otherwise working transmission would extend its useful life?

That's a question I would like the answer to as well Jon. I'm thinking of sticking a new valve body in mine if it is still in good nick inside, but is that the right thing to do? Mine only has 20 odd KKM since a rebuild, so I'm thinking it may be the right thing to do, but not 100% sure.

Pick up the beast tomorrow so will take some pictures and load them up to site ,hope I can get a sleep tonight a i cant wait to pick it up.

Originally Posted by bacicat2000

That's a question I would like the answer to as well Jon. I'm thinking of sticking a new valve body in mine if it is still in good nick inside, but is that the right thing to do? Mine only has 20 odd KKM since a rebuild, so I'm thinking it may be the right thing to do, but not 100% sure.

The Valve body issue seems to be only part of the big picture, the main pressure valve in the pump housing wears at a similar rate, this controls main circuit / overall line pressure so in effect it is just as important as the valve body, and as far as I am aware wears at a similar rate to the valve body bores.

I would suggest replacing only the valve body in a higher mileage 5L40E seems like a bit of a band aid. Could even lead to early wear of the new valve body due to overall pressure drop...It is a bit of a 'which is first? Chicken or the egg?' scenario. I was recently talked out of this action by a very knowledgeable 5L40 rebuilder. There doesn't seem to be any shortcuts with these gearboxes at all I'm afraid.



JC

Originally Posted by justinc

The Valve body issue seems to be only part of the big picture, the main pressure valve in the pump housing wears at a similar rate, this controls main circuit / overall line pressure so in effect it is just as important as the valve body, and as far as I am aware wears at a similar rate to the valve body bores.

I would suggest replacing only the valve body in a higher mileage 5L40E seems like a bit of a band aid. Could even lead to early wear of the new valve body due to overall pressure drop...It is a bit of a 'which is first? Chicken or the egg?' scenario. I was recently talked out of this action by a very knowledgeable 5L40 rebuilder. There doesn't seem to be any shortcuts with these gearboxes at all I'm afraid.



JC

So is there an up-spec main pressure valve in the pump housing?

hi slug,

unfortunately higher pressures mean harsher shifting etc. the bore also wears in the pump housing, the same problem as the valve body....chickens, eggs, etc etc...

jc

All this talk of TD6 engine L322 having gearbox issues is quite offputting. Maybe I would be better off saving more pennies and buying a TDV8 version.

After reading a lot of posts BigJon,, my conclusion is LR gearboxes wont tow anything worthwhile untill the 6 speed command shift came in.
Thats a really badly worded sentence , but you know what I mean,,

Originally Posted by justinc

The Valve body issue seems to be only part of the big picture, the main pressure valve in the pump housing wears at a similar rate, this controls main circuit / overall line pressure so in effect it is just as important as the valve body, and as far as I am aware wears at a similar rate to the valve body bores.

I would suggest replacing only the valve body in a higher mileage 5L40E seems like a bit of a band aid. Could even lead to early wear of the new valve body due to overall pressure drop...It is a bit of a 'which is first? Chicken or the egg?' scenario. I was recently talked out of this action by a very knowledgeable 5L40 rebuilder. There doesn't seem to be any shortcuts with these gearboxes at all I'm afraid.



JC

I have had the same advice here in Melb by experienced rebuilder, so have decided to examine oil at regular intervals and at slightest sign of any particles in the oil, go for a complete rebuild.
Peter