Rear Suspension:                                                                                               FAQ Home

Volvo Maintenance FAQ for 7xx/9xx/90 Cars                                                                                                                     Version 5.0

"Clunk" in Rear End: Bushing Diagnosis.  [Query:] 87 740 wagon with 190k, M46 trannie, new to us. Have replaced shocks, struts, u-joints, trannie mount and center support bearing on driveshaft, and some front bushings. Acceleration from standstill in normal traffic results in a "clunk" which seems to come from rear end.  Trannie output bushing and pinion bushing have no play. Wheel bearings are good. Nothing is rolling around in rear of car or spare tire well. The only thing I can figure is bushing(s) in rear, but which one(s)? (none are visibly broken up, although I haven't yet given them the prybar test.)  Can anyone guide me to the most likely culprit on this one?  [Response: Steve Seekins] I would focus on the rear suspension bushings. There are 7 - two on each of the torque rods and three on the sub frame to body mounts - one at the front and two at the rear. I would suspect the subframe mounts, probably got accelerated wear from soft torque rod bushings. The Haynes manual is adequate for procedures here.  Of course you should first check for loose upper or lower shock mounts or loose sway bar mounts. If the lower shock mount has loosened, check carefully for elongated hole in trail arm - if so, consider replacing the trail arm if tightening the bolt does not do the job.

Chock the front wheels.
Loosen the lug nuts.
Elevate one rear quarter of the car with the jack, and find a suitable place to locate a jack stand that will keep weight off the spring. I found a place right in front of the trailing arm where I was able to locate a jack stand. If it looks like it's gonna bite into the underside of the body shell, spread the contact zone out by inserting a piece of 4x5x.75" plywood or something similar between the jack stand and the car.
Remove the wheel.
Loosen the lower shock mount. The Haynes manual says to jack up the trailing arm slightly to take tension off the nut here. I don't recall if I did this, but it seems like a good idea. I seem to recall that I also had to loosen the upper one too, but you'll know it if you need to.
Remove the nut holding the upper spring seat in place. If you're replacing a Volvo spring, chances are it is not a variable rate spring, so you can get to the nut with just a ratchet wrench and a socket. If you're removing a variable rate spring, however, you'll probably need a fairly long extension.
Now at this point, I was able to lightly tug on the spring and it fell right out. I did NOT have to remove the brake caliper on either side, and I did not find the exhaust system to inhibit the removal or installation on the passenger's side. I began the replacement, prepared to remove the calipers, if necessary, but I found that there was plenty of clearance there, and I didn't have to touch them.
When you get the spring out, inspect the rubber seats for wear or deterioration. Replace if necessary.
If you're replacing your springs with variable rate ones (recommended), you'll need a long extension for your socket to reattach the upper spring seat because you won't be able to get your ratchet to fit comfortably between the coils until about halfway down the spring's length.
Reattach the upper spring seat. This was the most time-consuming part of the procedure -- getting that nut's threads to start was a bit tedious.
Reverse the above steps for the remainder of the installation.