my car struggles to engage in reverse gear

[patdavis]

i have a 55 plate vectra 1.9 cdti sri automatic..

it wont always engage in reverse any one help?

[mattv6diesel]

fluid level or the selector switch on the gearbox may not be quite in the correct place possibly theese are just gesses

[patdavis]

so the fluid level will effect the reverse gear engage? bearing in mind all the other gears are working fine!

[mattv6diesel]

may just be more the slection switch then not quite knowing where r is

[patdavis]

any one with any knowlage