Hi,


First, thanks for a great Volvo site :)


I have a problem with my Volvo 940 LT Sedan 1995 (tuned to 0.8 bar) that I can't seem to find nobody else having, so I'm trying here. I have stock suspension, and stock torque rods/panhard rods. Last summer the bolt in the lower torque rod broke right off inside the treads in the rear differential and the bracket welded on the rear axle tunnell got bent outward. I got it out, knocked the bracket on the rear axle tunnel pretty straight again and mounted a new bolt.


Now a few days ago, the same bolt broke off again when I had my throttle wide open, around 6 months after replacing it. I did the same procedure, but obviously this is only going to last for a limited time until I find out what's causing this bolt to become so stressed. None of my friend's 940's have the same problem.


A related problem might be that when my car is heavily loaded, like two persons in the rear seat or exactly at the bottom of speedbumps in an empty car; whenever the rear goes a bit lower, the car vibrates a bit when I accellerate, even when accellerating normally. The vibrations increase the harder I accellerate, and it sounds like a kind of grumbling/vibrating/bass sound coming from the back. My guess that something gets overloaded for some reason causing unusal stress on that bolt.


My rear suspension is in pretty good shape, and my rear is not unusually low when this happens. There is also a clunking sound that can be heard from the rear whenever I drive slow over big bumps in the road, if I turn sharply one way and turn the other it can sometimes be heard, or if I pull the handbrake while driving in a turn on snow. Now lately after replacing the bolt for the second time, I can also hear a clunk from behind when I've driven in reverse and put it in first, or vice versa, like something is not seated properly and shifts position depending on the direction the axle is loaded.


The bushings looks fine and nothing seems loose, though I did not try bending on stuff with a pipe or something to see the play. I've also changed the bearing/bushing at the center of the car holding the driveshaft recently, but the problem with the vibrations have always been there earlier so I don't think I assembled the driveshaft wrong.


Any idea what can cause the problem? I'm running out of ideas. I'll be very grateful if you guys have time to reply. :)

Best regards,
Christian