Best Coil Suspension Conversion Kit?

[Gregory891]

Sweep_the_Leg Sweep, you don't tell us the year, mileage and past (suspension or other) repairs to your X5.

Even with a conventional suspension, after time & miles or km, your shocks and other suspension parts will need replacement. The X5 had some known bushing & other parts that need attention every 5 to 10 years based on your roads, driving style, wheels (wide 18, 19 or larger diameter wheels will accelerate this).

I have a 2002 3.0 diesel (I live in Europe) with conventional front and air rear. Rear bags showed signs of cracking, so I replaced them proactively with Arnott products. Two hours start to finish, easier than with springs as you don't have to use a spring compressor. Bilsteins (B6 the yellow ones) as well.

I would suggest that repairing your front air struts is not any different as replacing shocks on a spring / shock suspension and WITHOUT the hassle of compressing springs.

Buy Arnott front air struts, easy to replace (they have lots of videos to show you). Look at your rear air springs and if you see visible cracking, consider proactive replacement - it's really quite easy.

[Sweep_the_Leg]

Mine is a 2005 with just under 79,000 miles. I don't know about any previous suspension work, as I've only had it for about six months and wasn't privy to prior service records when I bought it.

I ended up swapping out the factory front struts with Arnotts today. From the online research and calls I made, there is apparently not a single coil suspension kit that works on a 4.8is. Even KW told me that their coilover kit is not compatible.

The car obviously feels much better with the new Arnotts. I had slow leaks on both sides, which generally meant that car was having to pump itself up every time it sat for 8 hours or so. Steering is much more responsive and the ride feels both more stable and softer at the same time. Not surprising, I suppose, considering I was basically driving it around with both fronts at various stages of low to full inflation.

While I would rather have just put coils in and forgotten about the whole air system, the Arnotts weren't too bad. Once I get my core deposits back, and with the decent labor rates at my indy, the total damage will be a tad over $1300. I would have tried tackling the install myself in the driveway, but I've got too many other things going on right now.

[KyleNatolix5]

I'm not saying they are the greatest as I was only able to dig up with one review. The BC Racing Coils for the X, and the review was from one of the forum members X5girl. They will run ya just around a G note.

[TiAgX5]

Originally Posted by KyleNatolix5

I'm not saying they are the greatest as I was only able to dig up with one review. The BC Racing Coils for the X, and the review was from one of the forum members X5girl. They will run ya just around a G note.

You can read post #6 in this thread to see the why I think KW is pretty much the top of the heap (nothing worse then trying to save some $s on a labor intensive mod only to find dissatisfaction in the end result). I'm currently looking into a TOTAL Powerflex/heavy duty suspension bushing set to install with the KWs. With the ultra-stiff bushings there will be no excuses at alignment time to see a printout and hear "that's close enough" from the tech. I'm going for minimum camber/tow so the X is not a tire eater.

Having owned several coilover vehicles and setting corner balance/cross weights on my scales, I like the fact that the KWs have a low friction thread coating process that allows for adjusting without unloading the coilover (it sucks having to jack up, adjust, drop, re-settle the vehicle during the process).

[KyleNatolix5]

I'd love some KW's but for 3 grand it costs a pretty penny. I'm also looking into eibach sway bar kit, but the front is rare to come by.

[TiAgX5]

I've seen them as low as $2300. Currently $2600 on e-bay.

KW Suspension Variant 3 Three coilover Kit 01 06 BMW x5 E53 35220053 | eBay

[KyleNatolix5]

How's the warranty on the K&W?

[TiAgX5]

Originally Posted by KyleNatolix5

How's the warranty on the K&W?

Original owner has a lifetime warranty on defects. These are not covered for bottoming out/abuse (crash a curb and it's not covered).

The Var 2s on my Viper were $4000 and don't even have that warranty. Galvanised steel and no warranty for 4k (V2s) vs INOX Stainless steel and warranty for 2.3k (V3s), go figure.

I would troll e-bay and buy when a set pops up for $2300 or less, that's what I did.

[TiAgX5]

I wonder how many coilover owners actually set them up correctly.......

Adjusting The COMPRESSION (Bump) Damping Control (Very Important to do this FIRST!)
Bump damping controls the unsprung weight of the vehicle (wheels, axles, etc.). It controls the upward movement of the suspension as when hitting a bump in the track. It should not be used to control the downward movement of the vehicle when it encounters dips. Also, it should not be used to control roll or bottoming.

Depending on the vehicle, the ideal bump setting can occur at any point within the adjustment range. This setting will be reached when "side-hop" or "walking" in a bumpy turn is minimal and the ride is not uncomfortably harsh. At any point other than this ideal setting, the "side-hopping" condition will be more pronounced and the ride may be too harsh.

STEP 1: Set all four dampers on minimum bump and minimum rebound settings.

STEP 2: Drive a moderately bumpy road briskly to get the feel of the car. Note: When driving the car during the bump adjustment phase, disregard body lean or roll and concentrate solely on how the car feels over bumps. Also, try to notice if the car "walks" or "side-hops" on a rough turn.

STEP 3: Increase bump adjustment clockwise 3 clicks on all four dampers. Drive the car bumpy road again. Repeat Step 3 until a point is reached where the car starts to feel hard over bumpy surfaces.

STEP 4: Back off the bump adjustment two clicks. The bump control is now set. Note: The back off point will probably be reached sooner on one end of the vehicle than the other. If this occurs, keep increasing the bump on the soft end until it, too, feels hard. Then back it off 2 clicks. The bump control is now set.

Adjusting the REBOUND Damping Control
Once you have found what you feel to be the best bump setting on all four wheels, you are now ready to proceed with adjusting the rebound. The rebound damping controls the transitional roll (lean) as when entering a turn. It does *not* limit the total amount of roll; it *does* limit how *fast* this total roll angle is achieved. How much the vehicle actually leans is determined by other things such as spring rate, sway bars, roll center, ride heights, etc.

It should be noted that too much rebound on either end of the vehicle will cause an initial loss of lateral acceleration (cornering grip) a that end which will cause the vehicle to oversteer or understeer excessively when entering a turn. Too much rebound control in relation to spring rate will cause a condition known as "jacking down." This is a condition where, after hitting a bump and compressing the spring, the damper does not allow the spring to return to a neutral position before the next bump is encountered.

This repeats with each subsequent bump until the car is actually lowered onto the bump stops. Contact with the bump stops causes a drastic increase in roll stiffness. If this condition occurs on the front, the car will understeer; if it occurs on the rear, the car will oversteer.

STEP 1: With rebound set on full soft and the bump control set from your earlier testing, drive the bumpy road, paying particular attention to how the car rolls when entering a turn.

STEP 2: Increase rebound damping three sweeps (or 3/4 turn) on all four dampers and drive the road again. Repeat Step 2 until the car enters the turns smoothly (no drastic attitude changes) and without leaning excessively. An increase in the rebound stiffness beyond this point is unnecessary and may result in a loss of cornering power. Note: As with the bump settings, this point will probably be reached at one end of the car before the other.
However, individual drivers may find it desirable to have a car that assumes an oversteering or understeering attitude when entering a turn. This can be easily "dialed-in" using slightly excessive rebound settings at either end.

When I read posts that state "my car corners much flatter with my new coilovers", my thought is spring rates are too high or low rate damping is set WAY to stiff for street use, the vehicle is a wreck waiting to happen.

Stiffer sways reduce roll, and on roads with less then perfectly smooth paved curves, reduced unsprung weight helps increase control (this is where 315s on 20 or larger actually work AGAINST ideal control/handling.)


Some will argue this does not need to be done on a street vehicle, but undesireable handling is not something you want to experience during an emergency situation on public roads. Lives could be lost.

[///Bruce]

Originally Posted by TiAgX5

You can read post #6 in this thread to see the why I think KW is pretty much the top of the heap (nothing worse then trying to save some $s on a labor intensive mod only to find dissatisfaction in the end result). I'm currently looking into a TOTAL Powerflex/heavy duty suspension bushing set to install with the KWs. With the ultra-stiff bushings there will be no excuses at alignment time to see a printout and hear "that's close enough" from the tech. I'm going for minimum camber/tow so the X is not a tire eater.

Having owned several coilover vehicles and setting corner balance/cross weights on my scales, I like the fact that the KWs have a low friction thread coating process that allows for adjusting without unloading the coilover (it sucks having to jack up, adjust, drop, re-settle the vehicle during the process).

Just noticed something: you own a 4.4i. Yours does not count. It is not a self-leveling setup. Quiet!