96 965 Rear Shocks and Squeaking (Headache 2 of 2)

[ItWasTheSalmonMoose]

My 96 960 wagon’s rear suspension is driving me crazy!

I have a persistent squeaking that sounds to be coming from about midway down the right side of the car. It’s there all the time, but most audible when in drive and alternately releasing/applying the brake while in D. The car pitching slightly forward and back corresponds with the squeaking noise.

My thoughts were: shocks? trailing arm bushing? some other bushing?

I’ve replaced the shocks twice. Nobody in the world makes a production replacement shock for this car. Nobody. I got custom coilovers from Classic Swede which were great, but then one of the Gaz dampers failed and nobody nearby (Seattle) rebuilds shocks… My interim solution was to get the closest shock I could find in terms of Ext/Comp, end codes, and intended vehicle characteristics and modify to fit. That turned out to be a Gabriel G63708 shock for an Isuzu Trooper, for which I made custom bushing sleeves top and bottom to fit the M12 top bolt and 18mm lower stud on the trailing arm. It works, ish. With any weight in the back, the car sags a bit. (And before you ask: it’s a factory non-Nivo car.)

I’m fairly certain that the noise I’m hearing is not the shocks or their mountings. Could the trailing arm bushing squeak? Would it squeak that much? Could it be a different pivot point?

Thanks for your thoughts!

Here’s my replacement shock solution (plus frankenbumpstops). Forgive the Roadkill shim washer situation - I machined the sleeves too short and then no longer had access to a lathe and just had to make it work.
Notes:
1. The top sleeve (12mm ID, 3/4”(?) OD) needs to be solid all the way across the shock tower at the mounting point so it can get clamped by the bolt and not buckle the tower wall or allow vertical play. Couldn’t find an official length, so I measured this from the Classic Swede coilover bearing spacers as 2 11/64” (or 55.166mm - I only had an old imperial caliper). Use a hydraulic press to replace the stock sleeve with the custom one.
2. Don’t use Volvo replacement shock bolts (982848) for the top - they have a narrowed shaft which makes sense for reduced failure modes in some applications but allows too much play here. Just get some grade 10.9 regular M12x80mm half-threaded flange bolts.
3. For the lower sleeve the length is the uncompressed length of the bushing (1.75”). Use 2x 1/8” thick x 20mm ID fender washers on each side plus an M12 1/8” fender washer to compress bushing to 1.25”. The stud on the trailing arm is just about 1” overall length.
4. The bump stop replacement stock is GM part #15039397 - axle bumper for a Tahoe, etc. It needs shortening, trimming around, and a groove to get locked into the cup. It’s squishy enough to do by hand.