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2004 330i 6MT w/ZHP
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Discussion Starter · #1 ·
As a relatively new E46 owner, it wasn't until I was laid down in my driveway ready to perform my first maintenance that I realized I didn't actually know how to properly jack up the car and get it fully suspended on four jack stands. Having jacked up plenty of other cars in the past, I figured it couldn't be so hard, just look for the subframe and confirm my findings with a quick forum search. I quickly identified the rear diff or U-shaped subframe brace in that same area to be the proper jacking point for the rear. Then, all hell broke loose in my research on the front jack point. Dozens of threads later, I was still unsure of how to properly jack the front.

My car is a 2004 330i, so it has the aluminum undertray, bracing whatever you want to call it pictured here:
926208


From all of the threads I read, the donut looking indentation marked by the arrow seems to be the point of contention amongst forum members. Some swear that BMW officially considers this the front jack point and have jacked from this point for years with no issues. Others jacked from this point and immediately caved the whole thing in, had their car slip off the jack, etc etc.

I understand the front subframe crossmember to be directly behind that donut area of the aluminum tray, but not directly contacting it, hence why the aluminum crushes for some people when lifted upward. That is where my "idea" comes in: has anybody dremeled out a hole in the middle of that donut indentation and cut a matching block of wood to bypass straight through to the subframe for jacking purposes? Seems like this would be a good way to retain (most of) the rigidity of the aluminum, not have to remove the entire tray every time you need to jack the car, and also not risk any issues with stress on the aluminum or other jacking malfunctions. If someone can explain to me why that's a stupid idea, I'm all ears. In any case, I would love to know what people use as a front jack point for their cars as that is a fairly critical piece of information to have nailed down with certainty.
 

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2001 325i Sedan
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615 Posts
I jack it using the jacking points on the rockers. I place the jack stands centered under the outer aluminum part of the rear control arm mounts, or, in some cases, under the outer end of the control arms, next to the ball joints.
 

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Drive front wheels onto ramps and chock. Jack the rear using diff brace and then insert jack stands under two rear jack points. Push the car hard from several directions to insure solid support -- and get to work!

Creative and interesting idea! However, bmw considers the reinforcement plate a critical element. Meanwhile sharp angles (e.g. cuts) can concentrate significant stress. Cheers
 

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2004 325i automagic
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3,255 Posts
I use the rectangular area you pointed out on the aluminun reinforcement plate. Same as in the 50s kid "common repair steps" video on youtube.

It crumpled a little the first time I used it but has remained stable since then, and I always orient the jack saddle so that it fits into the imprint the same way. Sometimes I put a hockey puck in the floor jack saddle which makes contact with the plate. Either way I work quickly to get the front on the jack stands.

Word of caution for the rear, do not use the rear diff or you will trash the three rubber diff mounts. Lift only from the black metal subframe just in front of the diff.
 

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2004 330i 6MT w/ZHP
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Discussion Starter · #5 ·
Drive front wheels onto ramps and chock. Jack the rear using diff brace and then insert jack stands under two rear jack points. Push the car hard from several directions to insure solid support -- and get to work!

Creative and interesting idea! However, bmw considers the reinforcement plate a critical element. Meanwhile sharp angles (e.g. cuts) can concentrate significant stress. Cheers
Thought of that idea, it works great until you have a project that involves taking the front wheels off the car.

Interesting point. I find it hard to believe a 3”x1.5” hole or whatever the exact dimensions of that donut are would completely compromise the structure. It’s also no surprise BMW wouldn’t recommend consumers to go hacking at their car with power tools. Hard to say, hopefully I’ll get some more replies here.
 

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2004 330i 6MT w/ZHP
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Discussion Starter · #6 ·
I use the rectangular area you pointed out on the aluminun reinforcement plate. Same as in the 50s kid "common repair steps" video on youtube.

It crumpled a little the first time I used it but has remained stable since then, and I always orient the jack saddle so that it fits into the imprint the same way. Sometimes I put a hockey puck in the floor jack saddle which makes contact with the plate. Either way I work quickly to get the front on the jack stands.

Word of caution for the rear, do not use the rear diff or you will trash the three rubber diff mounts. Lift only from the black metal subframe just in front of the diff.
Sounds like you’ve used that point successfully but apprehensively. I was hoping this post and subsequent discussion would help me avoid the apprehension component. I attempted to jack from that point using similar technique to your hockey puck but with a block of wood, and stopped when I heard some creaks and cracks before the car was anywhere near suspended.

Thanks for the note on the rear diff, I will be sure to look out for that.
 

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2004 325i automagic
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Sounds like you’ve used that point successfully but apprehensively. I was hoping this post and subsequent discussion would help me avoid the apprehension component. I attempted to jack from that point using similar technique to your hockey puck but with a block of wood, and stopped when I heard some creaks and cracks before the car was anywhere near suspended.

Thanks for the note on the rear diff, I will be sure to look out for that.
I would say I am always a little apprehensive lifting the car with a floor jack until I have it on jack stands, and yes with the front reinforcement plate being what it is I am a little more apprehensive, but I still feel it is a viable lift point if used properly and carefully. Big caveat here is to use a floor jack with a wide saddle that will spread the force out. I would not use the tiny floor jacks with the very narrow saddle directly on the aluminum plate.

The hockey puck is nice because it sits in the saddle of the jack and isn't slipping off anywhere. With blocks of wood make sure they are not going to slip anywhere as the car rotates up. The metal on aluminum definitely is not slipping.

Check out the 50s Kid Common Repair Steps video for a demonstration. First couple minutes he shows how to lift and support the car.

 

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High-strength, single-use bolts x8 give insight on expected forces in the reinforcement plate. May also want to note the steel tubular construction of previous design. Agree it's ill-considered a single front jack point was not provided.

For the front, I'll either jack single wheel at a time, or use rear jack points to alternatively raise each side high enough to insert jack stands to the front jack point. For safety, be sure to use wheel chocks appropriately.

And, FYI, here's background on stress concentration, aka stress risers. Cheers!
 

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Depends on your jack. If you only have a regular 2T trolley jack then walk it up from the side jacking points. If you have a 3T lowpro jack use the dimple on the aluminium plate that you arrowed with the stands under the side jacking points. You can lift it up in one go then.
 

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'03 325iT Mystic Blau
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I jack the front from the reinforcement plate all the time, but then I'm not one of those people who view having a pristine reinforcement plate as some kind of badge of pride. It will show some scars if you choose to do so. What it won't do is catastrophically fail somehow as a result of using it.
 

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I highly recommend that you do not use the aluminum re-enforcement panel as a jack point. Why? The chassis relies upon the panel to stabilize the entire front suspension of the car. Using the panel as a Jack point can deform the panel. Now, if you must use the panel as a jack point, I suggest you place a piece of 1/2” plywood on the jack to spread the force across the panel. Otherwise use the rocker panel jack points.

Or buy a lift! /s
 

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//Binary is in my DNA
2002 BMW 325i
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4,276 Posts
I spent so much time and so many different ways to get the car in the air over the years. I am one of those that don't like bending the reinforcement plate so I went with the QuickJack a couple of years ago. Life has been so much easier, I can get QJ off the wall, under the car and in the air with all 4 wheels off in less than 10 min.

 

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If you like working on your car and expect to have this hobby for several years, just get a quickjack and be done with it. At ~$1200.00 it isn’t cheap, but dang, it’s the best purchase I have made for the garage. But, I have 3 old cars and my son has two old cars, so it gets used almost every week for something. Heck, I lift my cars up just to wax/detail so I dont have to sit on the ground or bend over so much.
 

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2003 330cic, 2003 325iT
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I have attached the TIS guide for jacking in the front with a trolley jack. It affirms that the jack point is for jacking.

It may make you uncomfortable, but it is the intended spot. The reinforcement plate attaches to the front subframe at that point.
If you don't want deformation of the bump, use a hockey puck. BMW has a special disc, but that seems excessive. I suspect most deformation is caused by the metal crenellations of the jack biting into the aluminum.

926236
 

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2004 330i 6MT w/ZHP
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Discussion Starter · #17 ·
I use that reinforcement panel jack point all the time, but always with a hockey puck. It works perfectly.
Seems as though the hockey puck is the more popular choice to distribute the forces when compared with a block of wood. A couple of others have mentioned the hockey puck now as well.
 

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2004 330i 6MT w/ZHP
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Discussion Starter · #18 ·
I spent so much time and so many different ways to get the car in the air over the years. I am one of those that don't like bending the reinforcement plate so I went with the QuickJack a couple of years ago. Life has been so much easier, I can get QJ off the wall, under the car and in the air with all 4 wheels off in less than 10 min.

Either this or a full on lift are the dream for sure! I’m jealous of your setup and the convenience that comes with it. Everything can be had for the right price. I may look into this long term.
 

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'03 325iT Mystic Blau
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Depending on how much ceiling clearance you have a two post may not be that unrealistic. For not a whole lot more than the quickjacks I'm keeping an eye out for MaxJacks which are portable two post units that bolt into your floor with anchors while in use. Even with my low ceiling I'll be able to get 30" under the car.
 

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E46 320ci M54, 2.2 170cv convertible '00
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The jacking point mentioned in TIS in my car is slightly bent. Seems is not so robust as it may seem...my indy too "doesn't like" it too much, I asked it about it.
I've read around the net to use use wishbones joints but I don't know if it is safe.
 
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