How To Mount Splitter Using Quick-Release Splitter Brackets
This splitter DIY guide will walk you through the install process using our Buildjournal Quick-Release Splitter Brackets for the E46 / M3. Splitter mounting to your chassis can be difficult, but not anymore. We’ve developed a 100% bolt-on chassis mounted bracket that uses a skeleton frame to support the rear of the splitter, which is new for our latest version enhancement. Quick-release is even quicker now. A huge evolution over our old V1 brackets.
If you have your own rear mounting solution we also offer the front brackets by itself without the skeleton brace. This splitter DIY will cover the installation for the Full Kit with Rear Support.

Splitter & Bracket Installation Instructions
⚠️ Disclaimer: This DIY does require you to lift your car so please use proper tools and follow all safety procedures if you choose to attempt. This guide is for your reference only. We are not liable for any damages or injuries that result from this guide.
2. Assemble Front Brackets
2.1 Use the picture here to assemble the bracket. Each side of the bracket is made with 3 main parts: main bracket, adjustment plate, splitter feet. It’s important the orientation is set correctly otherwise you will have alignment issues with the skeleton brace and rear bracket. Pictured on left is the left/driver side.
3. Install Front Splitter Bracket
3.1 Remove your front bumper and Kevlar/aluminum bumper beam. If you have the aluminum bar, you need to also remove the bumper shocks. For now, leave the bar and bumper off. Notice how the splitter feet lines up with the rear bracket.
3.2 Use the OEM nuts to hold the front brackets in place, but do not tighten all the way down. This will help with the splitter alignment in the next steps.
4. Align Brackets & Set Height
4.1 Insert the quick-release pin into the feet/adjustment plate and tighten down the thumb screws. This is important for the alignment. Your front brackets, adjustment plates and rear bracket should be loose.
4.2 Temporarily install your bumper back on to set the the splitter height.
4.3 Rest the jack on your splitter and jack up to the desired height. Make sure the frame is in place.
4.6 Secure the frame to the feet with the holes aligned and use a clamp to hold it in place while you adjust the rear bracket.
4.7 Make sure the rear bracket and frame are in contact with each other or else you’ll experience some back and forth deflection. Tighten down the rear bracket. Now your frame should be all set. Test for any play and adjust if necessary.
6.2 If you are using our Splitter Brace, you can install that during this step. This brace adds support for the front of the splitter for those not wanting to run splitter rods outside on the exterior of the car. It also doubles as a splitter skid plate.
6.3 If you are using our Splitter Rods with Shocks, you can install them now.
Buildjournal Splitter Bracket with Quick-Release
E46 M3
1 Comment
Leave a ReplyCancel reply
This site uses Akismet to reduce spam. Learn how your comment data is processed.
The DIY section is awesome on here. Wish I seen it while building my rear diffuser/splitter setup for my fit. I know the Fit doesn’t really need that haha but it’s more for aero in mind than yours which is chassis mounted. I mounted all my stuff to the existing bumper and built it from a PVC material to test out how I like the look. I’m still trying to figure out a few sections on how to mount them so it doesn’t fly off and your brackets gave me some ideas. Thanks!