I also recommend the H&R lowering kit. I would consider adding wheel spacers at the same time to top off the more aggressive look and check the front suspension thoroughly since you will have started the suspension teardown replacing the springs. Spacers that are secured to the hub and come with longer lug bolts are the best. There are several good options between $100 and $200.

While it always causes a debate as to whether there is a performance gain, a low restriction air box will at least make the engine sound better to most that like throaty exhaust sound. I don't have a suggestion as to which one or the price range as I went the Dinan route many years ago and don't keep track of what others like. I think it may be AFE.

There are many youtube videos on X5 exhaust mods--that might help you decide how far you want to go. According to your list of mods in your signature you already have an X pipe. I suggest you first look for a sound you like that only involves changing to a low restriction muffler as you are more likely not to do something that causes a headache producing drone. Or, depending on the laws of your state or how strictly they are enforced, you could weld in electric cutouts. That route would allow you to open them a little or a lot for an adjustable sound. Good cutouts run $400-500. I think the best quality are from DMH. The are also easier to install and to install in the right place than any others I know about.

Handling improvements may also improve your fun factor. Heavier sway bars, strut tower brace and wheel spacers would be a big change in how it feels and handles and be a nice complement to the lowering and spacers. Sway bars are around $500. Strut tower brace maybe about half that.

Since most of what we see when driving is the interior changing the color of the trim with vinyl wrap is quite popular. LED interior or exterior bulbs are any easy color and brightness change that you will notice. There are also a couple of options out there to upgrade to a touch screen if you have navigation. Touch screens are $700-900.

Transmission software will give you faster shifts in sport mode, changes the shift points and how and when it downshifts. You could also install an E46 M3 SMG paddleshift wheel. With the transmission software it is lots of fun. Software is about $300. I found a used wheel for $200.

What you do depends on what trips your trigger. I like to do some each type mod with gaps of time in between the next ones. That way when the extra fun and newness wears off I have some new mods to bring it back.

Usually among the first posts when someone asks about what upgrades or mods they might consider, are posts about--- save the money---you will need it for all the--sky is falling---sky is falling---expensive repairs that will happen tonight while you are dreaming of driving you X5 on the number 1 rated driving enthusiasts stretch of road in the world. My response is that I respect those opinions, now let's get back to my question about mods you suggest.

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X5 4.6 2002 Black Sap, Black interior. 2013 X5M Melbourne Red, Bamboo interior
Dallas