Front end shimmy

Anyone experienced front end shimmy left and right when accelerating only? I’m running 18’s with hub centric 12mm spacers. It was fine for a bit. Wondering if it’s steering or suspension related.

I'd follow this order of troubleshooting:

-Check to make sure the bolts are tight
-Make sure the wheels are centered on the spacers and that they're the correct spacers for the wheels
-Have the wheels and tires balanced
-Inspect the axles and control arm bushings

Having this kind of issue occur after recently installing used wheels and tires with spacers seems to be more than a coincidence.

I checked the lugs and they are all still torqued down. Car has 260,000 miles. No history of past. Rode fine for about a week and a half and then this started. The spacers fit the hubs and wheels perfectly. Very snug with no movement. It’s only during acceleration. Any other time it rides like a dream.

Any work on the wheel bearings done recently? If they're not properly loaded with the 200Nm+180° (or whatever it is) you can get speed-related shimmying.

I also had "the correct" spacers on a set of aftermarket rims and got shimmying. I took them off, wire-brushed the hub so it was all clean, put a layer of aluminum duct-sealing tape (basically one-side sticky tinfoil) around the hub, THEN the spacer, then the wheel...no mo' shimmy. You say yours are already very snug, but maybe there's some corrosion on the hub centre that makes it fit snug, but slightly off-centre (?).

Shouldn’t it happen contantly if it were the spacers instead of just under acceleration?

I dunno. ¯\_(ツ)_/¯

On mine, it was very speed-dependant; 0-60km/h - nothing; 65-70km/h - a little shimmy; up to 100km/h - nothing again; around 110km/h - jiggle-city.

Under acceleration could indicate something in the power transfer - CV joints / shafts maybe? Bolts that connect drive axles to transmission or the big bolt that holds hub to drive axle - maybe check torque on those (?). Start at the stuff that's easy to get to and move to the more difficult.

I hope that’s not a symptom of a DMF going out either

How does the DMF sound at idle? If you have a subtle "marbles in a can"-type rattle...that's DMF speaking to you.

How many miles on the car? The BRM's DMF had a pretty definitive lifespan - I don't know how many made it past 200K miles.

260,000 miles

I can’t hear ****. I’m actually getting hearing aids on Friday. I may be scared to drive after that lol