Hello guys, I have been doing research on ways of lowering the X3 comfortably and found a lot of mixed reviews. I thought it would be a good idea to put our suspension upgrades/reviews in one thread. There are a lot of threads about this, but its good to get a collective here.

Available for the F25 X3:
Coil-overs: Megan Racing (Lowers 1.00 - 3.00 inches confirmed with Megan), KW V2
Springs: H&R, Eibach, FK Automotive
Shocks: Bilstein B6 / B4 Sport / B4 OE, KONI Red

I'll start with my car!

Model: X3 xDrive35i
Original options: Standard W/O Sport Suspension, W/O DHP
Tires: Front 245/40 Rear: 275/35
Wheels: 20x9 ET35, 20x10 ET45 Stance SC-8
Suspension upgrades: None yet
Miles on new suspension: None yet
Location: Northeast with crappy roads
Picture: Coming up

Review your own suspension: My biggest issue with this car is the electric steering so I'm looking for ways to improve that. After I ditched the run-flats and installed wider wheels and tires, the handling improved A LOT. Next I will go into lighter wheels and some lowering springs/shocks.

I would like to try the Bilstein B4 Sport shock with FK Automotive springs that lower the car 1.5 inches and they are made in Germany and cost $70, cant beat that.

Your turn.

If you want to improve a BMW's cornering ability you have to remove the designed understeer. Swapping springs, shocks, tires does not remove it.

The only way to remove the massive understeer (BMW specifically designed the sway bars for driver safety to not fishtail) is to change the sway bars. Unfortunately BMW nor Aftermarket makes performance sway bars for the X3 to remove the understeer. 3 series and X1 owners can simply install M3 sway bars or buy aftermarket. That's the only thing that makes an M3 an M3 handling wise compared to a bog standard 320i, the sway bars.

Installing springs, shocks is a pointless modification and will only destroy the ride quality. They will not improve the handling abilities of the car as the factory struts/springs are more than adequate. The car will still understeer exactly the same because your limitation is the sway bars not the factory struts/springs/ride height.

Making an F25 corner is a dead end until someone in the aftermarket community decides to sell a proper rear sway bar but there's no market for it, so... kiss that dream goodbye. Save your money. If you're dead set on stance/looks throw on those FK springs but keep in mind you won't improve the car in any way except cosmetic.

I didn't include tires in this conversation because well, if you have 1 ounce of care driving a vehicle would have already ditched the shit ass run flats for a proper summer tire the day you bought the car. That is the biggest and only improvement to making a F25 handle that's currently available to us.

Riick wrote

If you want to improve a BMW's cornering ability you have to remove the designed understeer. Swapping springs, shocks, tires does not remove it.

The only way to remove the massive understeer (BMW specifically designed the sway bars for driver safety to not fishtail) is to change the sway bars. Unfortunately BMW nor Aftermarket makes performance sway bars for the X3 to remove the understeer. 3 series and X1 owners can simply install M3 sway bars or buy aftermarket. That's the only thing that makes an M3 an M3 handling wise compared to a bog standard 320i, the sway bars.

Installing springs, shocks is a pointless modification and will only destroy the ride quality. They will not improve the handling abilities of the car as the factory struts/springs are more than adequate. The car will still understeer exactly the same because your limitation is the sway bars not the factory struts/springs/ride height.

Making an F25 corner is a dead end until someone in the aftermarket community decides to sell a proper rear sway bar but there's no market for it, so... kiss that dream goodbye. Save your money. If you're dead set on stance/looks throw on those FK springs but keep in mind you won't improve the car in any way except cosmetic.

I didn't include tires in this conversation because well, if you have 1 ounce of care driving a vehicle would have already ditched the shit ass run flats for a proper summer tire the day you bought the car. That is the biggest and only improvement to making a F25 handle that's currently available to us.

I agree with everything you said, but my goal is not to make it corner flat, after all it is a small family SUV and its mostly my wife's car. To be honest I actually like the way it handles for the most part, especially for the standard suspension with flimsy sway bars. My goal is to lower it slightly without loosing too much of the ride comfort. I also would like the steering to feel a bit heavier and for the whole car to feel more like a BMW, solid and planted.

SHOCK/SPRING: I was set on going with Eibach springs and Bilstein shocks, but after finding a report that the suspension becomes bouncy and deflective I scratched that idea. I know that Bilstein Performance shocks are monotube and high pressure gas and they are a lot more harsher than a comparable Koni Yellow. Paired with Eibach springs, I see why it was a bumpy ride. A shock is made to absorb the imperfections on the road, not jump over them, so firmer is not always better. I think BMW did a good job with m-sport suspension for this car, but since I do not have sport suspension I would like to get something similar but better quality and lower ride. I think the best option would be the B4 Bilstein OE Sport Suspension direct replacement. I reached out to Bilstein to give me a better understanding between the B6, B4 OE, B4 Sport shock. Paired with a good spring (I think H&R) and the ride will be much better.

SWAYBARS: There are no options and thats a shame, so I will be going with m-sport swaybars, which are a few mm thicker and can be found at junkyards for cheap. A lot of X3 folks upgraded the shocks/springs and left the standard swaybars in place, which I think is a bad idea. Also, I think I will get the Ultra Racing strut brace, there a few reports of it positively affecting the steering feel.

Prices: B4 Sport shock all 4 corners $350, H&R Springs can be found for $200, Front/Rear m-sport swaybars $200, Ultra Racing Brace $100, for a total of $850 I think it will handle well. The only thing I'm still not sure about is the springs. I'm doing more research on the FK Spring since I never heard of it before.

Thanks.

Model: X3 xDrive28i N20
Original options: Standard W/O Sport Suspension, W/O DHP
Tires: Front 245/40 Rear: 275/35 RFT Pirelli PZero
Wheels: 20" OEM.
Suspension upgrades: Eibach Pro Kit for 35i
Miles on new suspension: about 30,000kms
Location: Toronto, mixed conditions. My wife knows to avoid potholes.

There's about 55,000kms on the car now. The stock shocks are starting to struggle over broken pavement and quite noticeable in colder climates.

I did notice on realoem that the rear sways on the X3 and X4 come in three different widths. Not sure what would have come on my model and if they can be swapped out.

x3sm wrote

SHOCK/SPRING: I think the best option would be the B4 Bilstein OE Sport Suspension direct replacement. I reached out to Bilstein to give me a better understanding between the B6, B4 OE, B4 Sport shock. Paired with a good spring (I think H&R) and the ride will be much better.

Went with B4 Sport + Eibach Pro Kit on my last A4 after the stock shocks failed. I thought it was a good combo.

pokerface wrote

Model: X3 xDrive28i N20
Original options: Standard W/O Sport Suspension, W/O DHP
Tires: Front 245/40 Rear: 275/35 RFT Pirelli PZero
Wheels: 20" OEM.
Suspension upgrades: Eibach Pro Kit for 35i
Miles on new suspension: about 30,000kms
Location: Toronto, mixed conditions. My wife knows to avoid potholes.

There's about 55,000kms on the car now. The stock shocks are starting to struggle over broken pavement and quite noticeable in colder climates.

I did notice on realoem that the rear sways on the X3 and X4 come in three different widths. Not sure what would have come on my model and if they can be swapped out.

Thanks for the reply! I thought the rear swaybars only had two widths.. I'll double check, maybe the M40i had even thicker swaybars.

pokerface wrote

Went with B4 Sport + Eibach Pro Kit on my last A4 after the stock shocks failed. I thought it was a good combo.

Good to know! Are you considering replacing the stock X3 shocks with B4 Sport? I just spoke to a rep from Bilstein and he said that B4 Sport (22-213136KT) is a bit shorter than B4 OE (19-197692KT) and said that B4 Sport is valved for a sportier feel. He also said that Bilstein HD and B6 are virtually the same and a lot of people that daily drive on these complain of the harsher ride. I believe B4 Sport is much better than OEM m-sport shocks. Since B4 Sport is a bit shorter I think it will do good with a shorter spring.

Does anyone know if there is a real difference between standard suspension spring and sport/DHP spring?

I would consider doing B4 Sport on the X3 when the time comes, but right now we don't feel a strong urge to spend on it.

I found the following rear sway bar parts:

33556787218 - 18.5mm diameter
33556787219 - 20.5 diameter
33506874434 - I can't seem to find the diameter on this right now.

For tires - the rears are almost to the wear bars so will need new ones. Considering my options. The 20" wheels and RFT tires are heavy.

pokerface wrote

I would consider doing B4 Sport on the X3 when the time comes, but right now we don't feel a strong urge to spend on it.

I found the following rear sway bar parts:

33556787218 - 18.5mm diameter
33556787219 - 20.5 diameter
33506874434 - I can't seem to find the diameter on this right now.

For tires - the rears are almost to the wear bars so will need new ones. Considering my options. The 20" wheels and RFT tires are heavy.

I think the 33506874434 has been discontinued, maybe it was too costly to offer a thicker swaybar? Because looks like it was only offered on X4 M40i

A thicker rear sway bar would really help with turn in and remove understeer.

x3sm wrote

Hello guys, I have been doing research on ways of lowering the X3 comfortably and found a lot of mixed reviews. I thought it would be a good idea to put our suspension upgrades/reviews in one thread. There are a lot of threads about this, but its good to get a collective here.

Available for the F25 X3:
Coil-overs: Megan Racing (Lowers 1.00 - 3.00 inches confirmed with Megan), KW V2
Springs: H&R, Eibach, FK Automotive
Shocks: Bilstein B6 / B4 Sport / B4 OE, KONI Red

I'll start with my car!

Model: X3 xDrive35i
Original options: Standard W/O Sport Suspension, W/O DHP
Tires: Front 245/40 Rear: 275/35
Wheels: 20x9 ET35, 20x10 ET45 Stance SC-8
Suspension upgrades: None yet
Miles on new suspension: None yet
Location: Northeast with crappy roads
Picture: Coming up

Review your own suspension: My biggest issue with this car is the electric steering so I'm looking for ways to improve that. After I ditched the run-flats and installed wider wheels and tires, the handling improved A LOT. Next I will go into lighter wheels and some lowering springs/shocks.

I would like to try the Bilstein B4 Sport shock with FK Automotive springs that lower the car 1.5 inches and they are made in Germany and cost $70, cant beat that.

Your turn.

I've got the H&R Sport Springs and like them a lot. Had them for about 20,000 miles and exactly 3 years now. I've posted my impressions of them and the drop expected, if you search for my threads. My car already had the Sport Suspension option, but without EDC, so YMMV when upgrading your springs.

It's too bad no one makes sway bars still for these cars.

I also compiled this list of Sport vs Regular suspension components of the two option packages. The springs, coils and sway bars are different part numbers for cars with Sport suspension. The Sport springs are firmer than regular ones, I don't know if you get much of a drop though.

If you are interested, I wouldn't mind selling you my OEM Sport springs. They only had 20,000 miles on them when I took them off.
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EDIT: I I was trying to figure out where I got the part numbers for the sport springs, and I think it was a total PITA, because they aren't officially listed for some reason. I vaguely recall I had to get them by calling the dealer. If you check yourself for your car, I don't think you'll see it.

This is what shows up when I search:

http://www.realoem.com/bmw/enUS/showparts?id=WX73-USA-06-2014-F25-BMW-X3_35iX&diagId=31_0395

But I'm almost positive that the Sport springs are different than the Regular springs. It wouldn't make any sense otherwise, for BMW to have provided different shocks and sway bars with the Sport package, but not different springs that are matched to the sport shocks.
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Lotus99 wrote

I've got the H&R Sport Springs and like them a lot. Had them for about 20,000 miles and exactly 3 years now. I've posted my impressions of them and the drop expected, if you search for my threads. My car already had the Sport Suspension option, but without EDC, so YMMV when upgrading your springs.

It's too bad no one makes sway bars still for these cars.

I also compiled this list of Sport vs Regular suspension components of the two option packages. The springs, coils and sway bars are different part numbers for cars with Sport suspension. The Sport springs are firmer than regular ones, I don't know if you get much of a drop though.

If you are interested, I wouldn't mind selling you my OEM Sport springs. They only had 20,000 miles on them when I took them off.
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.
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EDIT: I I was trying to figure out where I got the part numbers for the sport springs, and I think it was a total PITA, because they aren't officially listed for some reason. I vaguely recall I had to get them by calling the dealer. If you check yourself for your car, I don't think you'll see it.

This is what shows up when I search:

http://www.realoem.com/bmw/enUS/showparts?id=WX73-USA-06-2014-F25-BMW-X3_35iX&diagId=31_0395

But I'm almost positive that the Sport springs are different than the Regular springs. It wouldn't make any sense otherwise, for BMW to have provided different shocks and sway bars with the Sport package, but not different springs that are matched to the sport shocks.
.

Yeah they do not list any part numbers for springs on realoem so I think you are right, the springs are probably a bit firmer but don't give any drop.

When I spoke to a rep from Bilstein about the B4 sport shock and regular B4 shock, he said its different valving (which I expected) but he also said B4 sport is a shorter shock. I think that the sport suspension X3 sits a tad lower due to maybe 10mm shorter shock. This all makes sense because people with sport suspension on their X3 sit lower on H&Rs than people that have standard suspension with H&R spring.

I noticed that people with sport suspension and H&R springs like the ride a lot better than people with standard suspension and H&R springs and/or people with bilstein B6 shock and H&R springs. So, standard longer shock + H&R spring is a bad ride, bilstein B6 + H&R spring is too harsh of a ride, but B4 Sport shock with H&R is the better ride. To add, I noticed that people with bilstein B6 shock and H&R springs with OEM 18.5mm rear sway bar complain that the rear end is jittery, I think its important to upgrade rear sway bar to 20mm if someone is thinking of doing the harsh B6 shocks with lowering springs.

Anyway to know if sport suspension sporing is actually same length as standard suspension spring?

Also, do you think front sway bar is thicker on sport suspension?

x3sm wrote

Also, do you think front sway bar is thicker on sport suspension?

The bar for Sport and EDC -equipped cars is a different part number than that on standard suspension cars, which should indicate something thicker. Unlike on the rear, the part diagram doesn't actually specify the diameter in mm.

Bufalo wrote

The bar for Sport and EDC -equipped cars is a different part number than that on standard suspension cars, which should indicate something thicker. Unlike on the rear, the part diagram doesn't actually specify the diameter in mm.

Realoem specify that rear bar on sport suspension is 20mm and standard suspension is 18.5mm. But does not specify for the front bar

The rear bar bushings are sold separately, and so the diameter is called out to ensure that the right parts are chosen. The part number for the front bar actually includes the bushings, which aren't listed with their own separate number. So I still expect that the front sway bar is thicker. I mean, I'm willing to do some measuring on the Standard Suspension front sway on my car if anyone who has Sport or EDC could do the same.

Bufalo wrote

The rear bar bushings are sold separately, and so the diameter is called out to ensure that the right parts are chosen. The part number for the front bar actually includes the bushings, which aren't listed with their own separate number. So I still expect that the front sway bar is thicker. I mean, I'm willing to do some measuring on the Standard Suspension front sway on my car if anyone who has Sport or EDC could do the same.

If you could measure the standard bar, I can find one on eBay and ask a seller to measure it.

x3sm wrote

If you could measure the standard bar, I can find one on eBay and ask a seller to measure it.

Done - I measured 26mm at the point indicated.

Bufalo wrote

Done - I measured 26mm at the point indicated.

Interesting... Good to point out where you measured, because some sway bars taper at different points.

Bufalo wrote

Done - I measured 26mm at the point indicated.

Awesome, thank you. I found one on eBay.de but for some reason it does not let me sign in to contact the seller. I'll keep looking. If someone with sport suspension wants to measure it, would be highly appreciated!

Awesome thread!

ornithology wrote

Awesome thread!

Thank you sir!

It looks like I will test harshest suspension mode for my f25)))

I have HRE P40SC 21inch rims and Eibach lowered springs.
Just got Bilstein B6 and two sway bars from vehicle with a sport option S226A:
Front - 31356788711 (27мм)
Rear - 33556787219 (20,7мм)

Measured it in a two points - first point the same like Bufalo mentioned before and a second measurement is close to the link mount point.

HDBoss wrote

It looks like I will test harshest suspension mode for my f25)))

I have HRE P40SC 21inch rims and Eibach lowered springs.
Just got Bilstein B6 and two sway bars from vehicle with a sport option S226A:
Front - 31356788711 (27мм)
Rear - 33556787219 (20,7мм)

Measured it in a two points - first point the same like Bufalo mentioned before and a second measurement is close to the link mount point.

Awesome, thank you for the measurements!

We now know that front bar on sport suspension is around 1mm thicker. Not sure if it's worth the upgrade but nonetheless it gives people a choice. I think rear is definitely worth it!

Please let us know what you think about B6 shocks!

Also if you can take some pictures of the install of sway bars it would be very helpful