[F30MGM]

Hey everyone since my first BMW (E46 328i) I always wondered why my alignment felt so out of whack whenever I took it to firestone for alignment. I kept hearing all about things such as you need weights to align your car properly. So today I put together 500 lbs of concrete mix as weight to weigh the car down for alignment. I chose the 50lb bags from lowes/home depot to make the addition of weights easier(Even though they were slightly more expensive [<$2difference]. Last week I had it aligned after replacing my wishbone arms with F8x wishbone arms since the the car was extremely toed in afterwards, and it felt worse after I did a alignment on the rack than it did after i did my eyeball alignment. So I decided to try out the weighted down alignment method which includes:

Approx 150lb in driver seat
Approx 150lb in passenger seat
Approx 150lb in rear middle seat
Approx 50lb in the trunk middle(its really 46 but dumping out 4 lb of concrete was messy so i decided to overlook this detail)


Photo of weights in seats[ I combined 3x bags of 50lb concrete mix into one big bag, which now that I think about it, the process would be easier to have wrapped each of the 10 bags seperately, 150lb is no joke lifiting in to the car carefully.]





Alignment spec sheet before any alignment performed with weights in the car[These are the previous alignment specs that were done without weights in the car but for this reading there are weights in the car):


This is the alignment spec sheet after alignment is performed and with the weights still in the car:


This is the alignment spec sheet after alignment is performed and with the weights removed from the car:


Conclusion: Weights should be used when aligning your BMW, or maybe now that we have the specs with alignment performed with weights and weights removed you can use this value as the "compensated specs for no weights".

If anyone wants to give it a shot let us know how it goes

[Supr3me]

Thanks for posting this info. Nice to see the data behind this suggestion/requirement.
Here's my stack of sandbags for alignment use- little dusty now as I haven't needed them for a couple of years.

[kern417]

I have never used weights and will never use them. The fact of the matter is, you aligned the car with weights compensating for a specific setup, i.e. 4 passengers in the car. The moment you're by yourself with a trunk full of groceries, it's going to change.

What it sounds like is they didn't give you a good alignment. Your toe in settings are set so that it'll drive more neutral when you have weight in the car. Notice that your toe only changed up to 0.06*. If your toe in is 0.3+ with weight in the car, then it wasn't set properly without weights in the car.

The only time I'd consider it is if I was doing a track prep with corner balancing, and in that case I will sit in the driver's seat. But even for my amateur track day prep i have no issues after getting the car aligned with no weights in the car.

For the past 2 years i've been doing my own alignments using the string method. That way you always know you're setting it right and not worried about an inexperienced tech or equiment that's out of calibration.

[F30MGM]

Ive had my car aligned by different places over the years and for me I still feel like this is the best alignment I have ever gotten. Im just speculating here but maybe the loading with weights method creates some sort of preload for the drivetrain/suspension? Before my cars DSC light would keep coming on at high speed curves, now my car hugs the road even in wet roads(to an extent)

Taken from other forum:

The REAL Reason For Using Weights During Alignment? (No, It's Not What You Think.)

According to Dinan the purpose of the weights is to simulate the angles in the suspension when the car is driving at high speeds.

When you drive faster, you'd notice that your car "sits down" lower and closer to the road. As the car "sits down lower" the wheels spread wider.

This is caused by the aerodynamics of the car. Slanted windshield, slanted hood, underbelly, etc. BMW designed the car to go lower when you drive faster, not to go higher (float).

The alignment specs are therefor there, because they want specific numbers when you, the driver, need it the most - when you drive the car like it was meant to be driven. Not while you are at your shopping center parking lot driving speed. Makes sense?

The instruction by BMW is to do this:
1. Place the weights in the car.
2. Measure the height of the car: "fender to center of the wheel" to make sure the car is at the right height. The tolerance is 1cm (or a quarter of an inch IIRC - but it is very close to that anyway).

Anecdotal:

1)
I did my alignment a few time at a Dinan installer. He does it the way it is described above. His explanation to the use of weights was the down force at speed due to aerodynamics.

Results: With only me, the driver, in the car, and no passengers, the car handling and overall feel was "Amazing and Fantastic".

2)
I did my alignment twice at an indy shop that specialize in preparing and building M3 cars for race tracks. The owner does the alignment himself. In the past, BMW used him to travel around the country to teach dealership technicians how to do alignment. So this is a guy who teaches BMW how do alignment (it's worth repeating this twice).

The way that HE approaches the alignment is a little different than the above. He puts weights on the strut towers and in the trunk and keeps measuring the HEIGHT of the car (fender to center wheel) until the HEIGHT of the car is exactly in the middle of the spec provided by BMW. So basically, he doesn't care what the weight is. He just wants to make sure that the HEIGHT is perfect.

I asked him what's his purpose in doing it that way. HIS explanation is, that the purpose of the weights is to bring to suspension to be perfectly parallel to the ground. THEN you align the wheels to the correct numbers in the BMW spec.

After the alignment, he takes the car for a ride in some twisty back roads, that ends in a large empty parking lot where he will drive in a figure 8 at high speed making sure everything is just superb. Fun times.

It makes perfect sense to me.

Results: With me, the driver, as the only person in the car. No passengers. The car handling and overall feel was... you've guessed it. Beyond your expectation Fantastic and Amazing. You WILL feel the difference even if you are not Mario Andretti.


NOBODY EVEN MENTIONED THE WEIGHT OF PASSENGERS, ETC.

I DON'T KNOW OF ANY BMW DOCUMENTATIONS WHO MENTION WEIGHT OF PASSENGERS.

As a reference point: Up to that time, I used to take my car to a place who did my alignment without weights "because his machine compensated for the lack of weights in the BMW". He was very precise and I always watched while he's doing it. He always brings it to the middle of the spec. Guess what? The car felt "okay", but not even resembling the feel of the car after the two above shops did it using the weights. There was no resemblance whatsoever.

I can unequivocally say, based on my experience after the alignment, comparing the last one to the first two, that the first two guys alignment is perfectly correct, and the last one is absolutely wrong for the car. And that is AT ANY SPEED.

Do yourself a big favor and take your car to a shop that does the alignment like BMW says to do it.

Lastly, just a tip to the new guys looking for an alignment shop:
1. Ask if they use weights, if they don't, walk away.
2. Ask for a printout of the before and after. If they tell you that the printer is broken or they run out of ink or whatever other BS they tell you, walk away.
3. Try very very hard to go to a place that specializes in BMW or high end cars. Even if it means that you need to drive farther, or need to pay more.
4. Stay there to watch the alignment if at all possible (dealers will not allow you to watch, but they are ok of course).

Good luck!

MatWiz

[kern417]

Doesn't make a difference. It's dynamic, so improving your alignment at high speed with sacrifice your driving experience at low speed. Same with how many passengers you have, how much gas is in your gas tank, etc etc etc.

At the end of the day, most BMWs on the road don't break 100mph so it's pointless to "set your alignment for high speed." And you don't see everybody putting weights in their car to prepare for track days. I have no issues at the track or street doing an alignment with no one in the car, and realistically it will take a lot to actually improve your times/traction with an alignment that's dialed in to that level. My suggestion is either make sure the shop has calibrated equipment, or do it yourself.

[JeffHou73]

BMW only publishes specs for the vehicle when loaded with proper weights, as specified AND with a full tank of gas, also as specified. Anyone doing an alignment without the weights is, effectively, doing it with blinders on. It has nothing to do with how the car handles when loaded with passengers or not. It is simply the optimal angles for the car at a defined ride height.

Dealers all have specially equipped alignment software that eliminates the need to add weights. However, it does require that ride-height sensors be mounted to the top of all four wheel wells. With these sensors and the special software, you should, in theory, get a perfect alignment each time. And, you can definitely feel the difference!

However, many BMW technicians do not use the ride-height sensors so it is always good to ask before you have your car aligned. it takes less than 5 minutes to mount the ride-height sensors properly, but they sometimes just don't like to take the time to do it correctly.

[B58 parts]

The manual talks about normal position, weights throughout the car. Replicating the condition of a family driving around with a trunk full.

You may want to instead replicate race conditions, your weight in driver seat 1/2 tank.

I did my own alignment after the coilovers just with some string and a lot of time and everything is peachy. The car rotates alright but is a boat. Definitely need sway bars diff and bushings. I don't really want to touch the suspension again it may be getting rusty bolts.

One thing that did help after lowering was the adjustable sway bar end links. I was able to adjust and torque them with the wheels on the ground and weight on the seat. It was an interesting reach but somehow doable. There was a guy with a nice track e46 that had good videos about this.

[AspektUSA]

This is why i just let BMW dealers align my car.

[dmanb2b]

That rear toe is a little aggressive for my taste. People tend to think neg camber causes wear, but toe wear is the culprit and BMW specs to the aggressive side

[TheACN]

Do I need an alignment if I change oem wheels for a larger set of oem wheels? Very comparable overall diameter between the two, just better visuals.

[johnung]

Originally Posted by TheACN

Do I need an alignment if I change oem wheels for a larger set of oem wheels? Very comparable overall diameter between the two, just better visuals.

No. Shouldn’t need an alignment unless you were seeing uneven wear or some previous issue

[psubmw]

Originally Posted by AspektUSA

This is why i just let BMW dealers align my car.

Yes well, around these parts, the local BMW dealership service center alignment tech forgets to center your steering wheel, and when you try to talk to the service advisor and their manager, they talk down to you and insinuate that you're lying to them about what's been done to the car. I've never been treated so poorly in my life by a service center.

[Cytoplasm0671]

Originally Posted by psubmw

Yes well, around these parts, the local BMW dealership service center alignment tech forgets to center your steering wheel, and when you try to talk to the service advisor and their manager, they talk down to you and insinuate that you're lying to them about what's been done to the car. I've never been treated so poorly in my life by a service center.

Dealerships are often feast or famine. Always have been.

[psubmw]

Originally Posted by Cytoplasm0671

Dealerships are often feast or famine. Always have been.

Sucks.

[kern417]

Just saying I have multiple track days on my 340i at this point and I don't use this method. Alignment is a range and what works for some may not be optimal for others. If you really want a dialed alignment, don't take it to BMW. Take it to a performance shop that specializes in track prep.

[mjay2886]

Went through two alignments at the dealer. Not sure if they used weights or not. Steering wheel is not properly centered and car has a drift to the right in the center lane on the most even road I can find. I will post pictures below of the alignment before and after on first visit (blsck and white), followed by second visit in color. If there’s anyone with advanced mechanical knowledge that can provide feedback, please let me know.

I also provided photos of the passenger side tire, which seems to have a even line on the edge as if the car is not touching correctly on turns or straight away. I checked all other tires and they do not have that marking. The car is equipped with the M adaptive suspension package.

The car is a 2024 BMW M340i with 5,800 miles on it. The vehicle is not even a year old. Alignment is definitely better than the first one however does not feel solid as it was before I started experiencing issues. Car is riding super rough, I can feel the road dynamics more and all the bumps. I know the dealer put about twenty five miles on it doing a road test on my second visit. Maybe someone did a joyride who knows.

[weehe126]

Originally Posted by mjay2886

Went through two alignments at the dealer. Not sure if they used weights or not. Steering wheel is not properly centered and car has a drift to the right in the center lane on the most even road I can find. I will post pictures below of the alignment before and after on first visit (blsck and white), followed by second visit in color. If there’s anyone with advanced mechanical knowledge that can provide feedback, please let me know.

I also provided photos of the passenger side tire, which seems to have a even line on the edge as if the car is not touching correctly on turns or straight away. I checked all other tires and they do not have that marking. The car is equipped with the M adaptive suspension package.

The car is a 2024 BMW M340i with 5,800 miles on it. The vehicle is not even a year old. Alignment is definitely better than the first one however does not feel solid as it was before I started experiencing issues. Car is riding super rough, I can feel the road dynamics more and all the bumps. I know the dealer put about twenty five miles on it doing a road test on my second visit. Maybe someone did a joyride who knows.

Your front camber is different by 0.5°, that is probably the reason it is pulling to the side. Front toe and rear camber /toe are all good before and after. I am assuming the front camber is not adjustable just like it isn't on a F series. Since the car is band new I would ask why the camber is that far off, unless you hit a massive pot hole and bent something.

[mjay2886]

Took the car to my personal mechanic for alignment and here are the results with no weights used. Any input?