RacingDiffs All-Solution LSD for BMW 188K—forged clutch-type differential, front view; fits E46 3 Series, E39 5 Series, E38 7 Series, X3 E83, X5 E53, Z4 E85/E86 (free shipping).

All-Solution LSD Unit for BMW 188K Differential

Name: All-Solution LSD Unit for BMW 188K Differential
Brand: RacingDiffs
SKU: RD1010
Price: 1499.0 EUR
Availability: InStock

RD1010

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1.849,00€1.499,00€

Gear ratio

Low range (2.37 - 2.87) sold out

Mid range (2.93 - 3.07) sold out

High range (3.15 - 4.45) sold out

Qty

Transform your open differential into a real clutch-type LSD

BMW never offered a limited-slip differential for the 188K types from factory — until now. The RacingDiffs All-Solution LSD Unit brings true LSD performance to medium-case differentials such as type 188K across numerous BMW models including E46, E39, E38, X3 E83, X5 E53, and Z4 E85/E86.

This drop-in unit replaces your factory open carrier with a fully forged, clutch-type differential core that delivers maximum traction and race-grade reliability — while staying civil on the street. It uniquely combines up to 100% lock under full throttle with zero noise or chatter in tight turns, striking the ideal balance between performance and comfort.

Features

Plug-and-Play Installation: Direct swap for the stock open carrier — no welding, machining, or special setup required.
Clutch-Type LSD Behavior: Smooth, progressive locking for predictable handling and superior grip in all conditions.
Fully Serviceable Kit: Includes fully forged ramp plates, pressure rings, clutch packs, and preload springs.
Adjustable Ramp Angles: 30/60, 30/30, 50/65 and other options for street, track, or drift setups.
Fully Forged Construction: Every internal and external component is fully forged and thermally treated for maximum strength and longevity.

Performance Benefits

Eliminates the one-wheel-spin problem permanently.
Maximum traction and perfect corner-exit control.
100% lock on demand with silent, seamless operation in sharp turns.
Improved stability, lap times, and driver confidence.
Ideal for drift, track days, and spirited road driving.
Lifetime warranty and worldwide DHL Express shipping.

Technical Specs / Installation Tips

Differential types	BMW 188K
Lock type	Clutch-type LSD, fully forged internals
Ramp options	30/60, 30/30, 50/65
Max lock	Up to 100% under full throttle
Carrier preload	Set to 1 Nm
Backlash	0.06–0.08 mm at ring gear (measure with dial indicator)
Required parts	Backlash Adjustment C-Clip Set (for setting backlash & preload) + new OEM-spec side (carrier) oil seals + bearings (optional)

Ring-gear bolts: clean threads, apply medium-strength thread locker, and torque to 140 Nm in a star pattern.

Fitment — BMW 188K

Compatible with BMW differentials of type 188K. Grouped by chassis for clarity.

E46 — 3 Series

320Cd M47N · 320d M47 · 320d M47N · 320td M47N · 323Ci M52 · 323i M52 · 323i 2.4 M52 · 325Ci M54 · 325Ci M56 · 325i M54 · 325i M56 · 325ti M54 · 325xi M54 · 328Ci M52 · 328i M52 · 330Ci M54 · 330i M54 · 330xd M57 · 330xd M57N · 330xi M54

E39 — 5 Series

520d M47 · 520i M52 · 520i M54 · 523i M52 · 523i 2.4 M52 · 525d M57 · 525i M54 · 525td M51 · 525tds M51 · 528i M52 · 530i M54 · 535i M62

E38 — 7 Series

725tds M51 · 728i M52 · 728iL M52 · 735i M62 · 735iL M62

E83 — X3

X3 2.5i M54 · X3 3.0d M57N · X3 3.0i M54

E53 — X5

X5 3.0d M57 · X5 3.0d M57N · X5 3.0i M54 · X5 4.4i M62 · X5 4.4i N62 · X5 4.6is M62

E85 / E86 — Z4

Z4 2.2i M54 · Z4 2.5i M54 · Z4 3.0i M54 · Z4 3.0si N52

To confirm your differential’s final-drive (gear) ratio, just look it up in the BMW parts catalog, and follow this quick video guide.