gearbox some times loses 4th gear?

[TI3VOM]

Hi there I have a vt v6 commodore and every now and again it knocks back a gear from 4th to 3rd it can still use 1-2-3 but not 4th im pretty sure this is a shift solenoid but when I got holden to check the fault codes nothing came up I have searched on these forums and only found that most people have a different solenoid problem (different gear) I have a haynes manual but it does not have a fault code for 3-4 or 3-D.
Can anybody confirm this and if it is how hard is it to fix (myself) or a cost to get it fixed.
Thanks

 

[HARVZ-6]

How many ks?

when was last service?


my vt super6 did this from about 290thousand ks onwards.. basically the trans is just too tired, slippering etc getting hot and dropping overdrive because of a heat override... is the fluid clean pink colour or a smelly brown?

 

[White Tiger]

have a look at the linky in my sig

 

[nick3110]

ur link fails..

 

[White Tiger]

fixed it i think here's the link any way http://forums.justcommodores.com.au/general/117092-4l60e-problems-solutions.html

 

[TI3VOM]

My bad guys I forgot I even put this thread up.
K's: 212K's was doing it when I bought it at 193K's
Not sure when it was last serviced I've got trans fluit in my room right now just need the time.
Auto trans fluid is pink/red looks to be in great shape.
it seems to be affected by the heat so would that affect it more if its worn or could it possibly be electrical fault?