Lost overdrive in auto

[Avo]

hey guys was going for a drive last weekend loaded up camper trailer and half the car.half way along our journey I noticed on a hill the revs climb and little action.took overdrive botton off and it went fine.drove around all weekend,fine.drove 150 km home loaded just using d for drag without the overdrive button and it got us home no problem.so drive works and only have problem when in overdrive......I was thinking maybe oil change and a new filter casuse I haven't done it for about 4 yrs(50 000 km)but if it was this it would slip in all gears....yes...no.......it's probably cheaper to change to manual but I love my auto especially on the sand and the black top which is about 95%..the other 5% is on grass...I don't do mud

the car is a 4.2 diesel with auto...93 GQ.....


Just looking for pointers at what my problem may be.

Cheers

[Clunk]

Does it accelerate hard or us it sluggish?........... Well mire sluggish than a td 42 is I mean

[Avo]

hey Clunk everything is as before but if I put the overdrive button on it's like the transmission is slipping...But only in overdrive....every other gear it would still pull jesus crist off the cross....

cheeers

[Ian2011]

it might be the lock up clutch (sprag clutch) in the torque converter, this would need to be engaged in overdrive to provide the 1:1 drive. Could also be an electrical/solenoid problem within the valve body.

[shaunh]

my guess is lockup solenoid is dead

[lhurley]

It's an electric over drive so hopefully it's a simple fix. When I did my auto I tossed up putting a manual in (I prefer manual) but the mechanic building it made me stay with the auto by saying, yes I can do a manual conversion for around the same price, but with a brand new auto, I know the history, 2nd hand manual could have all kinds of issues waiting to pop up in a months time and I'm back spending more money on it.

[twisty]

Check you haven't got a leak from the radiator into the ATF system. That's what killed my auto. Hope not though, good luck.

[Avo]

@ twisty,nah mate stopped straight away and checkedsince no oil anywhere to be found.

Al;so thanks for the tips guys will question me amate about the solenoid...he works at Nissan ford spare parts in town here so I get most things at trade rates..

[Avo]

so I went for a drive this morning no load and it was fine for about 10km then started slipping,same on the way back so it is when the oil warms up..Hmmmmm

[Clunk]

I'd be dropping the fluid seeing as its been quite a while since last done.......... may or may not be the only issue though