Hello,
I have a 2.5TD with AR25 box.
There is an issue with the box once it warms up. Drives perfectly when cold though.
Fluid/filter change has been done three days ago.
It seems as if there is no fourth gear. If I run the box in "3", it operates as it should.
If I run it in "D" after some town driving, then when switching into fourth - be it from third or second, it goes "out of gear".
Basically when going 50kph (35mph), the car does not accelerate unless you rev it to about 3400 rpm. If you floor it at this point, the acceleration makes me think it's stuck in first.
If I rev it past the limiter, it changes into third gear with a strong jerk, and the box goes into limp mode (3rd gear only).
If I manually select "3", it goes into third gear, and can be driven normally.
There is no issue driving in "D" on the highway, overtaking etc.
Getting the software of the box upgraded, but I doubt that will do anything for me.
Does anyone know what the issue could be? 4th gear worn out? Some seals inside the box being weak and once the oil gets thinner with temperature not holding enough pressure to keep it in gear?
I haven't disassembled an autobox (yet). Friend of mine who did it for a living, said there is a disc (or drum, hard to translate) that wears out on these boxes, which enables fourth gear...