Whistling auto box

I have had this disco 2 auto for a month. Gear box changes ok, kick down fine, had an oil and filter change. When running it has a high pitched warbling whistle, anybody had this and what can I do to rectify, apart from turning the radio up.

worn boxes can whistle, you could check its fully sealed under the console

Are you sure it's the box? If it's a td5 then they're prone to warping the exhaust manifold and popping studs, this leads to a screaching / whistling noise under load.

Paul Leinichen said:

Are you sure it's the box? If it's a td5 then they're prone to warping the exhaust manifold and popping studs, this leads to a screaching / whistling noise under load.

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I think your right about the manifold, thanks, without stripping it all away to get a good look, what normally happens to them, and is it expensive?

ukamigo said:

I think your right about the manifold, thanks, without stripping it all away to get a good look, what normally happens to them, and is it expensive?

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The constant heating and cooling causes the manifold to warp slightly (mine ended up rocking by about 2mm when put against a true straight edge but that was quite extreme). The warping puts strain on the studs and usually ends up snapping a few, some snap just below the line of the head so you can't see till you try and take them out!
The result is that you will not get the manifold to properly seal even with new studs and a new gasket. Only option is to have it skimmed (resurfaced with a true flat face) then refit. Most engineering places can do this for you for not a great expense. If you have it skimmed, drill out the old studs carefully and refit new ones then it'll all go back together fine and usually it only happens once (when it's done warping then it won't warp anymore).
To give an idea of cost, I took to a local Land Rover specialist as didn't have time or a place to do the work myself and along with a couple of other minor jobs it cost £425 and that was 5 studs needed drilling out plus that was supply and fit new studs, etc.

Paul Leinichen said:

The constant heating and cooling causes the manifold to warp slightly (mine ended up rocking by about 2mm when put against a true straight edge but that was quite extreme). The warping puts strain on the studs and usually ends up snapping a few, some snap just below the line of the head so you can't see till you try and take them out!
The result is that you will not get the manifold to properly seal even with new studs and a new gasket. Only option is to have it skimmed (resurfaced with a true flat face) then refit. Most engineering places can do this for you for not a great expense. If you have it skimmed, drill out the old studs carefully and refit new ones then it'll all go back together fine and usually it only happens once (when it's done warping then it won't warp anymore).
To give an idea of cost, I took to a local Land Rover specialist as didn't have time or a place to do the work myself and along with a couple of other minor jobs it cost £425 and that was 5 studs needed drilling out plus that was supply and fit new studs, etc.

Click to expand...

thanks for that info, at least I know what it is now, I was convinced it was the box, did it affect your emission and fuel economy?