

- #Bmw e46 m3 subframe reinforcement cracked#
- #Bmw e46 m3 subframe reinforcement mod#
- #Bmw e46 m3 subframe reinforcement series#
This is to hold the lube in and prevent squeaking while the trailing arm is rotating inside the bushing. Looking at the RTAB you’ll see a knurling texture inside. This will put pressure on the bushing evenly and not smash them against the chassis when tightened down. These bushings also come with flat washers. There are top pieces and bottom pieces, all labeled from Powerflex. If you look at the Powerflex subframe bushings you’ll see they are notched and indexed so they fit just like factory ones. Urethane diff bushings are the ones that usually cause vibration and so I am keeping the ones I have.
#Bmw e46 m3 subframe reinforcement series#
The Black Series line is Powerflex’s harder 95A durometer bushings, but don’t fret, these will not cause vibration.

I chose to completely replace the OEM subframe bushings with Powerflex Black Series bushings .

#Bmw e46 m3 subframe reinforcement cracked#
You will have to remove the subframe bolts and washers to really see if/how cracked yours are. Factory BMW bushings are black in color making it very difficult to see tiny cracks without a flashlight. The Powerflex inserts will keep the OEM bushing from flexing and causing damage to the chassis. If your bushings are not yet cracked you can get the Powerflex inserts made for OE bushings. This will replace the factory bushing and they are made with a flange so they work like having limiters on.įor the subframe bushings, you also have two options. Powerflex offers Black Series urethane RTABs for the E46. Instead of getting new OE rubber bushings, I decided to go with urethane aftermarket ones. But the proper way to fix this is to press out the RTAB and replace them. These are urethane spacers that keep the factory rubber RTAB in place from moving too much. If your factory ones aren’t cracked yet or you’re on a budget then you might be able to get away with installing RTAB limiters. This is classic bad rear trailing arm bushings (RTAB) in action.įirst let’s address the easier of the two problems, the RTAB. Every time the rear wheels hit a pothole or bump I could feel the rear end wanting to slide around.īad rear trailing arm bushings will cause the rear wheels to toe in or out on their own too, steering the rear of the car all over the road. After that, the floorboard can’t really take all the movement and the load so it starts cracking.Ī second problem I was having was the car would feel like the rear was getting bump steer. How does this happen? Basically, it starts when the subframe bushings go bad. So you really have to disassemble the entire thing and clean it to know. And small cracks won’t give much of any symptoms. But small cracks will be under the subframe bushing and will not be visible until you remove the subframe. Large cracks might be visible if you had put the car up on a lift, use a lot of light, and scrape away all the dirt. The tiny cracks start to form where the subframe bolts to the car. The trunk floorboard is where the subframe bolts to the chassis and this is where the metal will start cracking. So there’s quite a lot of load that transfers from the drivetrain and suspension to subframe and then to the sheet metal underside of the unibody. Like most FR cars, the rear subframe bolts to the chassis via four mounting points. The entire rear suspension, rear brakes, and arms all attach to the rear subframe as well. The subframe is just the tubular frame that cradles the rear differential. So when people say that the subframe is cracked or reinforced they are inaccurate. Literally, every one of my friends with an E46 has had this repair (6 out of 6 cars).įirst off it’s not the subframe itself that cracks or goes bad. Possibly even not worth the value of the car. You’ll want address this problem because if it continues to get worse it will become very costly to fix. Is your car knocking when you shift hard or accelerate abruptly? If it sounds like a light thud coming from the rear of the car it could be your rear subframe coming loose behind you. Which means if your car hasn’t had this done, you will be doing it. And the shitty thing is to fully check a car, you have to remove everything in the rear, so you might as well repair it while you have the subframe and all out. I’ve seen it on unmodified cars, early models, late models, low mileage, and high mileage.

And it has nothing to do with how modified the car is. But the rear subframe issue is the real Achilles heel of the E46. Rod bearings, VANOS, or SMG pumps are not uncommon and not cheap or easy repairs.
#Bmw e46 m3 subframe reinforcement mod#
The E46 might be the most popular M3 chassis to mod by enthusiasts, but like all cars, they have their common problems. If you have a BMW E46 or are in the market for a used one, you might have heard of the rear subframe issue.
