Hi I posted in the new members area but thought ild post here too.
We have a 95 s 2.5 that engages into reverse but doesnt excelerate back motor just revs, it selects all other gears fine but just wont reverse it has had 3 different boxes put in all resulting in same issue, any ideas?

 

Have you driven the car around?

 

is there a flashing arrow warning light on the dash?

 

You said its a 95 s 2.5? What is that?

and

Your saying you put 3 transmissions in it and they all did the same thing?

 

Has the same shop or person done all three transmissions ?

Have the three transmissions been new or used ?

How many if any miles have each lasted ?

What kind of time frame, first failure was how long ago ?

 

One gear box after another re con direct from volvo, sent back gearbox twice coz all resulted in no reverse, they tested befor sending the last one said it definatly worked, 15min of driving no reverse, volvo said they couldnt help yes car is drivable, drives like a dream, 2.5 litre 850 1995 wagon. We know what the flashing arrow is about, by the way we are in esperance western australia

 

Have you tried cleaning your P-N-P switch?

Being that they are OEM transmissions I doubt you got 3 bad ones.
When the reverse goes out on these transmissions the B2 clutch is worn, but that doesnt seem to be the case in your situation..

This is all assuming you have a auto trans..

If its a manual it is most likely a linkage issue

 

Yeah auto transmision if the pnp is under the air intake yes we have cleaned that it shifts through the gears fine

 

How are the splines on your axles?
the only other thing i can think of is the TCU

 

If the pnp isnt aligned properly cld all gears work, but reverse? Why do u ask about the splines on the axle?

 

If the car thinks the axles are coming out it will lock the car movement down.

Can you feel the car shift into reverse? I was wondering if the parking brake had something to do with it.

 

It drives forward and rolls back when in reverse could the line pressure solenoid have something to do with it?

 

I don't know. If the PNP is working properly, I'd likely change the computer.

 

The line pressure would be the same for the forward gears as it is for reverse.

If you've replace the original failed transmission with two rebuilt units and all three are missing reverse I'd have to say it's something external to the transmission itself.

I don't know what to point at but it's just not possible for all three to have the same problem.

 

We couldnt get the line pressure solenoid to activate when we put power directly to it, u can feel reverse engage it has enough momentum to move back on flat ground in reverse but wont excelerate back, its like it all working fine just no exceleration to reverse, has us puzzled.

 

Park break isnt working either havent look into why yet, but since car moves back illiminated it from affecting the reverse gear

 

make sure there is enough fluid, 1/2 a quart more if you can. I never opened a Volvo transmission but if it has a transmission pump it could be too weak. My dad had a Chevy van that we had to put in an extra quart over limit to fully engage reverse. Torque converter and tranny pump were bad.

Are you using the torque converter from the other transmissions?