Spec X5 Overland Build

[Henn28]

The pups and I escaped Iowa between storms late Tuesday afternoon. Had to cut our trip short, but the weather was atrocious. We had a short break on Tuesday afternoon where the snow mostly stopped and the wind hand not picket up yet to a raging howl, as forecast. I will say that the Quaife was an expensive upgrade, but is definitely not on that list of the upgrades I've done to the X5 and struggled to justify afterwards. Just having one differential that isn't open on that X5 made a huge difference in how it handled in some really terrible conditions. 95% of the time it was seemless in how it moved torque to the wheel that had traction, but occasionally I did find myself tapping the brakes to fool it into thinking it had a little traction on the slipping side. Its not a true LSD in this respect so if you have zero traction on one side, it will still try to send all the torque there. Tapping the brakes (or the DSC working) will force the worm gear magic within the diff to work and transfer torque to the other side.

Happily we found lots of quail for a change and flushed a lot of very, very wily late-season phez. The highlight of Monday was getting locked out of the X5 by my 9 year old dog who I left in the car to rest. Unfortunately I opted not to load a crate in the X5 this year and I foolishly left the keys in the center console because we were in a hurry. Few other sinking feelings match the realization that you are on the outside of your X5 and your pissed off 82 lb bird dog is in the inside and won't let you in, and that you are soaking wet, its 25 degrees out and the wind is blowing to 30 mph in a remote Iowa corn field...and its getting dark in an hour. I can imagine him banging around the inside of the X5 trying to figure out why he got left in the car while that other dog he lives with didn't, and stepped on the door lock. There are no bad dogs, just stupid owners and I proved that. Fortunately my buddy talked me out of breaking the small window on the rear door so we got dry clothes at his house which was somewhat close and some tools. Long story short: we wedged the front passenger door open at the top/left jamb with wooden shims (he's a carpenter) and ended up snaking some very heavy gauge wire with a hook bent into it and lifting the handle a bit. I then held this arrangement while he snaked another piece with a loop on it and got it around the handle and yanked once to unlock. Like I tell my kids, life is about the stories you are able to bore your grandkids with someday...so make them good.

1950 round trip miles and the X5 was a beast. Nothing like 20 degree weather, ice and 40 mph winds to make me anxious about the strange noises the car was making.


Some were just because it was so cold and the car was covered in ice most of the time. Doors frozen shut, ice in the seals, wheel wells and undercarriage caked, etc. Some need attention though, at some point.

I'm still fighting a slow speed knock over bumps from the front right. The new monoball tension struts are pretty amazing, but neither those nor the new Bilstein struts fixed that problem. Looks like lower control arms are next as I've read that those can cause a slow speed knock. I have a new set of ball joints (tension strut ends), but that will wait until I need some bloody knuckles as the first hex bolt I tried to get out stripped immediately. They did feel pretty tight though when I replaced the tension struts.

The car developed a slight but very distinct whine from 30 to 40 mph only. Very much like alternator whine through the stereo but only after a cold start and it would stop when the brakes were tapped (drive side versus coast side of the pinion/ring gear maybe?). I'm pretty convinced that this is from the new diff, and must either be an output bearing(s) or the backlash. The backlash was at the very upper end of what Quaife said was acceptable, but I didn't want to pull the pinion. I suppose it could be the pinion bearings too, ebay donor differentials being what they are. I've read that its tough to put too much pre-load on output bearings, but I suppose it could be coming from there too. At any rate, I'm going to drain it next week and look at the magnetic plug. If it is relatively clean with no chunks, I'm going to close it up and live with it for a while. My 1993 grand Cherokee has had massive backlash issues and bearing whine from the rear diff for 15 years and it still makes it to the X5 rescue scene every time. The good news is that I've got the OE diff than came out of my X5 in my shop so I can break that down at my convenience and learn how to rebuild a pinion, set preload, etc.

I will say though that the ride with the Turner monoball tension struts is noticeably tighter and the car corners really well. The ride is a bit stiffer too. Nothing uncomfortable, but noticeable. This is likely in combo with upping the pressure on the Geolanders to 35 PSI in a fruitless quest for slightly better MPG, and the new Bilstein B4s up front too. I'm a fan of the mono-ball and will remain so if they they last longer than 2 years. I'll go with the turner monoball lower control arms to match and install them in the next few weeks. I'm going with complete struts and arms so I can hang on to the 2 year old ones that came out. If the monoballs fail too soon, I'll be disappointed for sure but I can try the poly bushings guys like and put them into these (now spare) struts/arms.

Finally, I definitely need a new tie-rod boots as mine are rock hard and the left one has shattered. They are the OE tie-rods so I think I'll replace them (inners and outers). Have never done tie-rods so any advice is welcome. I know I need a huge crows-foot, or maybe a special tool to take the inner one out, and a special pliers to install the inner boot clamps? Can this job be done without removing the stiffener plate? Also, if I'm careful and measure the old tie rods/count threads, can I do the job and not need an alignment afterwards?