Buy BMW 325i Suspension Trailing Arms

The BMW 325i rear suspension trailing arm-also called a trailing link or rear control arm-guides each back wheel so it can move up and down without sliding side-to-side. It affects ride comfort, tire wear, and rear-end stability. When its bushings crack or its metal bends, the car may wander, shimmy, or wear tires unevenly.

The arm pivots on a chassis-mounted bushing and holds the rear wheel carrier, letting the wheel travel in an arc as the suspension compresses or rebounds trailing-arm basics. (Wikipedia)
Because BMW uses a semi-trailing layout on many E36, E46, and early E90 3-Series cars, the arm also sets static toe and camber angles that keep the tire flat on the road in a turn E46 DIY guide. (E46 Fanatics)
Engineers call the piece a form of "longitudinal control arm," meaning it mainly controls movement front-to-back, while lateral location is handled by bushings and other links control- vs. trailing-arm thread. (Jeep Wrangler TJ Forum)

• 1992-1998 E36 325i/328i models share a steel trailing arm with serviceable bushings. (YouTube)
• 1999-2006 E46 325i uses an aluminum semi-trailing arm; bushing size and mounting points match 323i/330i siblings. (E46 Fanatics)
• Early E90 (2006-2011) keeps a similar design but adds lighter alloys and revised bushing durometers for ride comfort. (YouTube)

• Rear of car "steers" or feels loose on bumps or under braking forum report. (Bimmerforums.com)
• Clunk or thump shifting from Drive to Reverse noise video. (YouTube)
• Uneven rear-tire wear or cupping tire-wear article. (eEuroparts)
• Rear toe goes out of spec quickly after an alignment alignment forum post. (BIMMERPOST)

1. With the car safely lifted, grab the rear wheel at 3 & 9 o'clock-rock it side-to-side. Excess play hints at tired bushings. (YouTube)
2. Shine a light at the front trailing-arm bushing; look for cracks, missing rubber, or metal-to-metal contact. (E46 Fanatics)
3. Check arm tube for rust or dents if you live where roads are salted. A bent arm alters camber. (Bimmerforums.com)

• Common torque for E46 rear trailing-arm to subframe bolts: 110 Nm (81 ft-lb) torque list. (E46 Fanatics)
• Always preload the suspension at ride height before final tightening to avoid twisting the bushing rubber bolt-guide. (Garagistic)
• Press-in bushing tools or a simple threaded rod with sockets can remove old rubber on-car DIY video. (YouTube)
• After installing new bushings, schedule a four-wheel alignment to reset toe and camber. (BIMMERPOST)

The semi-trailing design means static toe increases slightly as the suspension compresses; worn bushings exaggerate this, making the car dart on bumps E46 guide. (E46 Fanatics)
Factory toe is usually set to 0.10°-0.20° in; camber about -1.5° on stock ride height, but lowering kits may need adjustable bushings or eccentric bolts to stay in range toe-correction video. (YouTube)

Enthusiasts swap in harder polyurethane or monoball trailing-arm bushings for sharper turn-in, though ride noise rises suspension discussion. (race-dezert.com)
Adjustable rear lower control arms let you fine-tune camber for track tires on E36/E46 cars install PDF. (ECSTuning)

Driving with a cracked trailing-arm bushing can let the rear wheel toe out under load, lengthening stopping distance and stressing the subframe safety article. (CarParts)
When using aftermarket arms, be sure they accept factory-spec wheel-speed-sensor brackets so ABS and DSC systems keep working properly. (YouTube)

Q: What is another name for the trailing arm?
A: Many mechanics call it a rear control arm or trailing link because it "controls" wheel motion along the length of the car. discussion thread. (Reddit)

Q: How long do BMW trailing-arm bushings last?
A: On stock 3-Series cars they can exceed 80,000 miles, but aggressive driving or rough roads may cut life in half. owner feedback. (BIMMERPOST)

Q: What noise points to failure?
A: A dull "clunk" when shifting from Reverse to Drive or a thud over small bumps often comes from worn bushings letting the arm hit its bracket. noise video. (YouTube)

Q: Does changing ride height affect the arm?
A: Yes-lowering the car alters trailing-arm angle, adding negative camber and toe-in; corrective toe-shim brackets or adjustable bushings fix it. toe-correction video. (YouTube)

Q: Can I re-use the old bolts?
A: BMW specifies new stretch bolts for the arm-to-hub carrier joint to keep clamp load; always replace them during service. torque list. (E46 Fanatics)

Q: Will worn trailing arms fail inspection?
A: Many safety checks fail cars with cracked bushings or loose arms because they can let wheels steer on their own. safety article. (CarParts)

Q: Are there upgrades for track use?
A: Solid-mount monoball bushings or tubular arms shaved for weight give sharper response but raise cabin noise and cost more. performance chat. (race-dezert.com)

Q: Do E36 and E46 arms interchange?
A: The complete arm assemblies differ in length and bushing size, but many aftermarket bushings fit both, so check part numbers before ordering. DIY video. (YouTube)