Hey there. I'm hoping someone can help me figure this out. I have a 1995 volvo 940 with 199k.
A short while ago the tranny started dropping out of overdrive at random times. Around the same time a mysterious squeal started.
The squeal is coming from the rear passenger side of the engine compartment. It is definetly not a belt or any kind of metal on metal rubbing.
It is usually worse when the engine is cold and then eventually goes away. It seems to come and go at various RPM's but seems to more or less increase or decrease following the RPM's when it does occur. It happens in all gears including park and neutral.
I checked the tranny fluid. The level was fine, no bubbles, it smelled a little funky but not bad.
Could it be a tranny problem? I'm hoping no, but my gut is telling me otherwise. Any input would be greatly appreciated. Thanks.

 

The thing to do is change the tranny fluid for starters, you say it smells funky... I have never seen this in a Volvo, you may have a belt squealing and totally unrelated to the tranny... The dropping out of OD may be unrelated, I'd try changing the relay first.

 

Does it only squeal when the vehicle is moving or does it happen while parked? If it happens only when moving and changes with the speed, then it could also be the center driveshaft bearing.

If it isn't speed dependent and occurs when parked, then I would suspect a belt. I have read of cases where a clogged trans filter also causes squealing noises. How dirty was the trans fluid? Dark brown? Cherry red? Somewhere in between? If it was not red, then I would recommend flushing the trans and pulling the pan to inspect/replace the filter.

 

The squeal happens in both drive and park. It also happens when in neutral if the car is still cold.
The belts seem fine and have good tension.
This weekend I'm going to drop the tranny pan, swap the filter and see what happens. Thanks for the replies!