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Description
e46 gear ratios BMW M Gear Ratio Swap Set | M3, M5, M6, Z4M Differential UpgradeBMW M Gear Ratio Swap Set Complete Installation Kit Enhance the performance and driving experience of your BMW M3, M5, M6, and Z4 M with the RacingDiffs Gear Ratio Swap Set. The kit includes all essential components to change your differentials gear ratio with factory level precision and reliability. Key Features Complete kit: All parts required for a precise, repeatable gear ratio swapno guesswork. Performance gains: Tailor acceleration and
BMW M Gear Ratio Swap Set — Complete Installation Kit
Enhance the performance and driving experience of your BMW M3, M5, M6, and Z4 M with the RacingDiffs Gear Ratio Swap Set. The kit includes all essential components to change your differential’s gear ratio with factory-level precision and reliability.
Key Features
- Complete kit: All parts required for a precise, repeatable gear-ratio swap—no guesswork.
- Performance gains: Tailor acceleration and drivability to your use case (street, track, time attack).
- OEM-level precision: Components manufactured to meet or exceed OEM specifications.
- Guided install: Step-by-step tutorial + video walkthrough linked below.
What’s in the Box
- Adjustment Shim Set — aligns and positions internal components correctly.
- Pinion Oil Seal — prevents leaks and maintains optimal lubrication.
- Large Pinion Bearing — required to install onto the new pinion from your new gear set.
- Crush Sleeve Shim — sets the correct pinion bearing preload.
- Pinion Position Shim Set (2.5–3.5 mm) — precise pinion depth adjustment.
Performance Benefits
- Stronger acceleration with the right final drive for your build and tracks.
- Optimized top-end and gear spacing for your engine’s power band.
- Long-term reliability when backlash and preload are set correctly.
- Expert support from RacingDiffs if you need guidance selecting shims or ratios.
Technical Specs / Installation Tips
| Use case | Gear ratio change on BMW M differentials (see fitment variants below). |
| Pinion setup | Set pinion depth using the Pinion Position Shim Set (2.5–3.5 mm) and establish correct preload with the Crush Sleeve Shim. |
| Backlash | Adjust with the Adjustment Shim Set until backlash is within spec; verify gear contact pattern with marking compound. |
| Sealing | Install the new Pinion Oil Seal; lightly oil lips; ensure no nicks on yoke surface. |
| Torque notes | Clean threads; apply medium-strength threadlocker on ring-gear bolts; torque in a star pattern per BMW spec. |
| OEM references | Backlash adjustment shims: 33139065736 (33-13-9-065-736 / 33 13 9 065 736 / 33.13.9.065.736) 33139065737 (33-13-9-065-737 / 33 13 9 065 737 / 33.13.9.065.737) |
Tip: Always re-check preload/backlash after first heat cycle or track day.
Fitment (Variants)
Variant 1 (V1):
- E36 M3 (3.2 S52)
- E46 M3
- E28 M5, M535
- E34 M5
- E39 M5
- E24 M6
- E60 M5
- E63 / E64 M6
- Z4 M
Variant 2 (V2):
- E90 / E92 / E93 M3
If you’re unsure about compatibility, send us the last 7 digits of your VIN and we’ll confirm the right set for your car.
Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- Standard Shipping : 3-10 business days
- If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
- We offer a 30-day return/exchange service after receiving.
- Final sale items are not eligible for returns or exchanges.
- To process your return/exchange, please contact us at [email protected]
- Please click here for more details>>> Return & Exchange Policy
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Product Reviews
★★★★★ 5
Very light and effective trimmer
Style: 20V String Trimmer Kit
I’m very well designed trimmer that cuts through grass and weeds very easily. The battery lasts about 45 minutes. It’s fairly light and easy to use. I think it’s also a pretty good value.
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Reviewed in the United States on March 12, 2026
★★★★★ 5
Perfect trimmer for my yard.
Style: 20V String Trimmer Kit
Works great. Love all the features for the price. I can get two yard trims out of 1 battery charge which is fine for me.
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Reviewed in the United States on May 28, 2026
★★★★★ 4
Nice unit, but poor user's manual
Style: 20V String Trimmer Kit
The unit itself is very nice. Seems sturdily built and is lightweight. Adjustable length works well and locks securely. I question the need for two speed control, but their claim is the lower speed saves battery power. I am not sure how much of a difference it makes and changing speeds in use is not very intuitive. A better choice would be an in between speed which is permanent to get better cutting and a little longer battery life. My annoyance comes from the lack of much information about the "automatic line feed" and how it operates. The fact is, the user's manual is bare bones for user information. The booklet is small, is divided into three languages, and all of the "icon" diagrams to explain things are so small you need a magnifying glass. I wanted to know what triggers the line feed, how it knows to lengthen it, and how it knows to stop feeding. None of that information is in the book or on the Black and Decker website videos. Aside from that, the unit is built well and should be durable. It is a good value for the money.
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Reviewed in the United States on November 4, 2025
★★★★★ 5
Black & Decker battery grass trimmer tool
Style: 20V String Trimmer Kit
Top quality battery operated Black & Decker Cordless String Trimmer ; . Assembly was very easy, only a couple pieces, not too heavy , versatile. ; What is great about the Black & Decker battery operated tools is that you can use the 20v battery with other Black & Decker tools that are out in the market. also, an extra battery can be purchased.. Tool as good instructions if you need it .
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Reviewed in the United States on May 15, 2026
★★★★★ 5
Light weight and easy to handle
Style: 20V String Trimmer Kit
This is my second one. Light weight and easy for me (old woman) to handle. Unit rotates so you can edge. The old one lasted right at 6 years. My old batteries work on new unit also. I get the one with the wheel which makes it much easier to edge. This one auto feeds and my old one didn’t. I don’t know how I feel about the auto feed. Another brand I had before with auto feed stopped working. That was a pain to manually feed. Have only used the new one twice
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Reviewed in the United States on April 17, 2026