Front Centre Jacking Point For Non-M

[Ruofdez]

Now I know there are threads asking about this but I’m yet to find one with a definitive answer despite much searching.

I have a pre-facelift non-M Z4. Is there a front centre jacking point?

Without this it makes getting the car onto 4 axle stands very difficult. Would like to do this in order to change the gearbox and diff oil and thinking the more level the car can be the better.

 

[tadekk]

I have a post-facelift so would like to know either.

As far as I know the best practice is to lift one side from the rear jacking point to place front axle stands, and then lift from rear centre point to put rear axle stands.

 

[mjennings23]

Technically, you'll be told no. If you have a rectangular jacking pad designed to fit into the sill jack points, you'll notice the rear of the undertray has a similar size indent. Right behind this is the front subframe of the car, so a perfectly safe point to jack from.

Ive used this every time I've needed to lift the entire front of the car (albeit that's only been twice in 2 years) and it's perfectly stable. It'll dent in a bit of the undertray most likely, but consider the M has the exact same subframe with a hole cut out of the undertray at this point, and you'll see why it's not an issue.

You will, however, have to drive the front wheels up onto a ramp or wood blocks to get to it, unless you have a very long, very low jack.

In summary, much like any car the subframe can be used to support the weight with no concerns, it's just there's a thin metal tray in front of it.

 

[Ruofdez]

Thank you both.

tadekk - Good point, that would do the job though I’ve found to get much height at the front you have to jack the rear of the car very high and it all feels a bit unstable.

mjennings23 - That’s pretty definitive and what I was hoping for thank you very much.

Just for anyone reading I found this with photos on jacking up the Z4, albeit on an M model hence this question. But might make it a bit clearer for some and shows the rear jacking point too - https://www.zpost.com/forums/showthread.php?t=484468

 

[MrPT]

The metal undertray is structural. Note the seriousness of the bolts holding it on!

It isn’t cool if you dent it as it will reduce its ability to act as a brace or make it pull/twist the chassis (or both).

 

[G600]

consider the M has the exact same subframe

I can't say I've had them side by side to compare but they are a different part number

 

[Ewazix]

The metal undertray is structural. Note the seriousness of the bolts holding it on!

It isn’t cool if you dent it as it will reduce its ability to act as a brace or make it pull/twist the chassis (or both).

Beat me to it, crushing it destroys its structural integrity and the rigidity it was giving to the front end. Its not an under tray.

 

[MrPT]

It is weird that it has that little indentation though, isn’t it? Wonder if it was a factory jacking point of some kind.

 

[Jakg]

I lifted mine (for diff oil / gearbox oil, same as you) the opposite way around.

Jack at the rear jacking point to lift up one side, and put an axle stand under the front jacking point, then remove the jack.

Jack at the rear jacking point on the other side - the car was slightly nose heavy so the rear went up instead, but with literally one hand you can lift the car at the front and it will pivot and put an axle stand under the other front axle.

With the front on stands, then you can jack under the diff brace and put two more under the rear jacking points.

 

[tomrdy]

I usually jack up the front end by lifting off the pinch weld near the front jacking pad - leaving enough room to get the axle stand under the pad.

Then I lower it so that the stand is holding via the rubber pad. Repeat for other side.

There's a lot of debate/discussion on the internet about whether pinch welds are safe to lift from. Mine have never deformed and I've never had an issue - but I ALWAYS leave the car on the actual pads when getting under or working on it once up, leaving the jack sitting slightly off-load under the pinch weld point i lifted from as an extra measure.

I actually never thought twice about it as all my previous cars had shaped indents on the pinch points themselves with instructions in the manual to lift with a scissor jack. Then one of my friends (who admittedly is.. well a bit of a overreacter about these type of things) had a big faff about getting an adaptor pad because XYZ etc etc.

My 2c!

 

[Ruofdez]

Thanks to all who've replied. There seem to be enough people that think it's a bad idea to put me off and so I think I'll either be getting some ramps for the front wheels and then use the rear jacking point to keep things nice and easy or I'll give Jakg's technique a go. The ramps might allow me to get a bit more height so my nose isn't pressed up against the underside of the car.

Hopefully this thread will be helpful for others who've been struggling to figure out what should be a pretty straightforward process!

 

[mjennings23]

The metal undertray is structural. Note the seriousness of the bolts holding it on!

It isn’t cool if you dent it as it will reduce its ability to act as a brace or make it pull/twist the chassis (or both).

Let me rephrase, as what I've said there arguably sounds worse than it is. (Likely due to my poor wording!)

If you have a jacking pad the correct size and shape for the rubber sill points, it also fits perfectly into the little indent on the metal tray. Using this and lifting will cause no denting or bending of anything. The tray sits flush against the structural cross-member at this point. The use of the correct shape lifting pad means the weight is transferred directly from the cross-member into the jack. Lifting in this area without this lifting pad WOULD bend the outer bits of the indentation in.

I've done it a couple of times and had the undertray off since to do the oil level sensor, you'd have a much better eye than mine if you could tell any difference between the tray off my car and one thats new (wear marks notwithstanding)

 

[MrPT]

Let me rephrase, as what I've said there arguably sounds worse than it is. (Likely due to my poor wording!)

Sorry, didn't mean to jump on your post if it came across like that. I'm not sure whether the cross member behind the non-M plate is actually structural, but I would assume so. Safe enough with the right adaptor.

I actually jack using the pinch welds on mine quite a lot, like tomrdy, which I know would scare a lot of people, but I use rubber adaptors and have found the "jack one side from the rear" approach to result in scary amount of "see-sawing", as mentioned above. Maybe because the M is a little more nose-heavy?

 

[Bing]

It is weird that it has that little indentation though, isn’t it? Wonder if it was a factory jacking point of some kind.

That indentation on the M has a rubber jacking point in it. Maybe it's just efficient production using the same part, slightly modified on the M.

 

[Ruofdez]

Came across this thread and thought it might be worth a read for anyone interested in the topic - https://www.bimmerfest.com/forums/showthread.php?t=333658

Implies that the way to safely do it is to remove the aluminium reinforcement plate - Part shown here - http://www.realoem.com/bmw/enUS/showparts?id=BT53-USA---E85-BMW-Z4+3.0i&diagId=31_0642




Some have apparently cut a chunk from the reinforcement plate to allow installation of the jack pad found on the M and I don't think they would have gone to the hassle of doing this unless it was worthwhile, so it does seem to suggest that jacking up directly from the aluminium reinforcement plate is a bad idea.

 

[mjennings23]

https://www.newtis.info/tisv2/a/en/e85-z4-3.0i-roa/repair-manuals/00-maintenance-general-note/00-02-raise-vehicle-tow-away/FiJt7rY

The fact that BMWs own factory repair manuals show it as a safe lifting point means more to me than hearsay on the internet. You'll notice its very explicit about having to remove the metal under tray from the rear before using the rear diff as a lifting point. No such qualifications made about anything at the front.

 

[Ruofdez]

https://www.newtis.info/tisv2/a/en/e85-z4-3.0i-roa/repair-manuals/00-maintenance-general-note/00-02-raise-vehicle-tow-away/FiJt7rY

The fact that BMWs own factory repair manuals show it as a safe lifting point means more to me than hearsay on the internet. You'll notice its very explicit about having to remove the metal under tray from the rear before using the rear diff as a lifting point. No such qualifications made about anything at the front.

That's a fair point, can see the arguments on both sides

 

[mjennings23]

https://www.newtis.info/tisv2/a/en/e85-z4-3.0i-roa/repair-manuals/00-maintenance-general-note/00-02-raise-vehicle-tow-away/FiJt7rY

The fact that BMWs own factory repair manuals show it as a safe lifting point means more to me than hearsay on the internet. You'll notice its very explicit about having to remove the metal under tray from the rear before using the rear diff as a lifting point. No such qualifications made about anything at the front.

That's a fair point, can see the arguments on both sides

Obviously just do what you're comfortable with, as I said I've used the centre point multiple times with zero issues, albeit I don't have a jack that can reach it without lifting the front wheels a bit anyway... massive pain!

Typically use the side jack points to lift the front wheels and putting a block of wood under the wheel, dropping down and swapping sides before finally getting to the front centre point and stands under the side pads. Used to be able to use a ramp, but the splitter on the car has done away with them plans

 

[Piper1]

To solve this issue entirely could always invest in a quickjack. Used mine for the first time last week wish I would've gotten it a long time ago.

 

[Ewazix]

https://www.newtis.info/tisv2/a/en/e85-z4-3.0i-roa/repair-manuals/00-maintenance-general-note/00-02-raise-vehicle-tow-away/FiJt7rY

The fact that BMWs own factory repair manuals show it as a safe lifting point means more to me than hearsay on the internet. You'll notice its very explicit about having to remove the metal under tray from the rear before using the rear diff as a lifting point. No such qualifications made about anything at the front.

Take care the document you linked to is NOT a BMW factory repair manual at all!, on the home page it says "newTIS.info is not an official source of information and is not affiliated with BMW in any way". Its wrong and is showing a schematic of of the ///M which has jacking point access, the rest of the range don't. If you check any manual supplied with a non-M car the front point is not a safe jacking point because it's a light alloy honeycomb brace that will crush and will lose it's structural integrity.