[Antares713]

When I floored the gas pedal, a strange grinding, rattling noise started coming from the engine. My local BMW dealership has a customer appreciation day deal for a 65$ oil change. I took my ass in there for oil and diagnostics.

The techs found the issue. The engine mount had failed and was starting to collapse, leaking hydraulic fluid.

I purchased the car last year as a CPO with 24k miles. The extended warranty has been useless and only covered the oil housing gaskets when they needed to be replaced. I need them to cover the mounts and struts. Its the most expensive warranty. My last two 335i's had all sorts of leaky problems so I jumped all over the warranty deal.

Car currently has 70k miles.....lol yea I have put on around 46k miles in one year.

Has anyone else had the engine mounts fail this fast? or to the point it fails and starts leaking. Also, does anyone have links to upgraded engine mounts that will last longer than OEM or that are performance versions.

I saw this
https://www.bimmerworld.com/Engine-M...PFF5-5452.html

I do drive my car hard asf. Autocross, drifting and just aggressive all over. Not wreckless! Lol, just the right amount of ooommph.

[Planoser]

I have around 40K and could feel my driver side mount was bad. I ordered 2 new oem mounts along with those power flex inserts with the red poly.

I installed the driver side mount today, and sure enough the original failed - all the liquid spewed out all over the floor and i could wiggle the mount post with one finger.

I can feel a big difference with the new mount and insert, however there is definitely an NVH increase - especially at idle.

[JacobM340i]

I’m at 85k, just replaced both of my mounts, drivers side was shot and leaking fluid, car still vibrates at idle slightly, so no fix in that but at least I got new mounts in.

[F32Fleet]

Aggressive driving will cause mounts to fail sooner. I'm at 73k miles and my mounts are in great shape but I don't autocross and I take it easy except for on the hwy.

[Planoser]

Originally Posted by JacobM340i

I’m at 85k, just replaced both of my mounts, drivers side was shot and leaking fluid, car still vibrates at idle slightly, so no fix in that but at least I got new mounts in.

I noticed idle vibration after I did the motor mount inserts, however if I tack up from idle(650rpm) to like 750rpms , it smooths things out. I wish there was a way to easily increase idle speed!

[helmet91]

Originally Posted by Planoser

I have around 40K and could feel my driver side mount was bad. I ordered 2 new oem mounts along with those power flex inserts with the red poly.

I installed the driver side mount today, and sure enough the original failed - all the liquid spewed out all over the floor and i could wiggle the mount post with one finger.

I can feel a big difference with the new mount and insert, however there is definitely an NVH increase - especially at idle.

How difficult is the install?

I'd have access to a lift...

[Planoser]

Originally Posted by helmet91

How difficult is the install?

I'd have access to a lift...

With a lift should be easier than on ramps like I did. You’ll need to make sure you have a way to lift the engine up while the car is elevated. There are a few videos on YT.

[JacobM340i]

Originally Posted by Planoser

I noticed idle vibration after I did the motor mount inserts, however if I tack up from idle(650rpm) to like 750rpms , it smooths things out. I wish there was a way to easily increase idle speed!

Same here, 650 it vibrates a little, 750 it’s like the engine is off it’s so smooth. Only difference is I don’t have inserts so idk what’s going on haha, maybe it’s normal. Ive discovered that if I know im gonna be idling for a while you can wiggle the steering wheel back and forth a couple times and it will bump the rpm’s up to 750 and make it smooth, probably not the best for the tires but oh well.

[Planoser]

Yeah, I’m trying to get my hands on ISTA to see if it can adjust idle rpm.

[BMWBruce]

This seems to be a common problem and I am surprised no one makes polyurethane, or at least more sturdy oil filled engine mounts for these cars. It seems ridiculous to treat an engine mount as something that needs to be replaced every 30 - 40k miles. Is there a solution for the B46/48 other than OEM replacement?

[helmet91]

Black forest has a whole new assembly
https://www.ecstuning.com/b-black-fo...i77-mg20-601~/

VTT has this insert that supposedly works on all G series
https://x-ph.com/vargas-bmw-g-series...series-insert/

I really don’t understand why Power Flex doesn’t have a B46/8 application.


**Returning to this one**
ECS Fitment guide shows the BFI mount working with the 230i and 330i... yet the cross reference part numbers (OEM) they provide all point to 240i/340i part numbers as per RealOEM. BFI's site just lists G20/22/42: https://blackforestindustries.com/pr...1Fb6258LLvyqjj
Seems like it's probably worth calling them before plunking down $600.

[Antares713]

Originally Posted by helmet91

Black forest has a whole new assembly
https://www.ecstuning.com/b-black-fo...i77-mg20-601~/

VTT has this insert that supposedly works on all G series
https://x-ph.com/vargas-bmw-g-series...series-insert/

I really don’t understand why Power Flex doesn’t have a B46/8 application.

Very nice find! Thanks

[VeryValidValidation]

Very recently I have been experiencing a almost knocking type of noise, almost like when you hit a bump on a flat tire, coming from my left side during WOT Gear Shifts. This happens in Sports Plus mode haven’t tested others yet. Is this what others with failed engine mounts have experienced? There is not shaking during idle. I left my SO step on the gas to see if there is extreme movement per Vehicular DIY vid (at the beginning) on the mounts here: VDIY’s VID .

I’m planning lifting up the car this weekend to confirm. Just trying to see if I can save sometime and just order new mounts and possibly the bushings that help.

Also would Front Engine Damper help at all? eBay link here: Engine Dampers

2020 BMW 330i 63k miles

[ladoo22]

Originally Posted by VeryValidValidation

Very recently I have been experiencing a almost knocking type of noise, almost like when you hit a bump on a flat tire, coming from my left side during WOT Gear Shifts. This happens in Sports Plus mode haven’t tested others yet. Is this what others with failed engine mounts have experienced? There is not shaking during idle. I left my SO step on the gas to see if there is extreme movement per Vehicular DIY vid (at the beginning) on the mounts here: VDIY’s VID .

I’m planning lifting up the car this weekend to confirm. Just trying to see if I can save sometime and just order new mounts and possibly the bushings that help.

Also would Front Engine Damper help at all? eBay link here: Engine Dampers

2020 BMW 330i 63k miles

This just started happening to me a few days ago. Taking my car in tomorrow and my mechanic was saying it’s the engine mount making contact metal on metal after the engine moves from acceleration and settles back into place. He’s gonna diagnose tomorrow but wanted to still see how things turned out for you and any update on repair?

[VeryValidValidation]

Originally Posted by ladoo22

This just started happening to me a few days ago. Taking my car in tomorrow and my mechanic was saying it’s the engine mount making contact metal on metal after the engine moves from acceleration and settles back into place. He’s gonna diagnose tomorrow but wanted to still see how things turned out for you and any update on repair?

Couldn’t get out last weekend because it rained all day and sinuses lol. But I did verify with a YouTuber that it’s the same thing he experienced. I am waiting to take the car to the dealership, hopefully extended warranty covers. If not going to dive in myself.