The squeaky noise is from the REAR balljoint going bad. At 170K, you bet money it is gone.

I don't have DIYs for E53 but I wrote FRONT and REAR suspension oevrhaul for the E39, you can use it as a reference:

DIY: 1998 BMW 528i COMPLETE FRONT SUSPENSION OVERHAUL - Bimmerfest - BMW Forums

DIY: 1998 BMW 528i Complete REAR Suspension Overhaul - Bimmerfest - BMW Forums

It's not always the ball joint:)

At 170K on original suspension parts your best bet is to refresh the rear suspension including the ball joints, otherwise you will be chasing squeak after squeak.

Exactly. That's why I said one of three.

how many hours were each job? how close are the 5 series suspension to our x5's

I had the infamous control arm squeak on a previous suv and my mechanic suggested a quick fix since the ball joint which was a "lifetime sealed bearing" must have gotten moisture inside the boot: poke a hole in the boot and shoot a squirt of wd40. Obvouisly as an "end of life" scenario to get a few months of use and maintain my sanity. The ball joint was tight just lost its lubricant and wow it was insane. Every tiny bump in the road squeaked.


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Yes the ball joint squeak is insane. You can almost look at it and make it squeak. On the control arms, you have to hit a liltle more of a bump to get a squeak. Oil does help for a while on the ball joints, not so well on the control arms........ I guess that could be a way to find out exactly which of the three items are squeaking. Either way, the op should just replace all the items. With all the parts, and tools ready to go, this is an easy Saturaday project. I think it took me about 5-6 hrs the first time. I split it up, two evenings after work.

changed my rear upper control arms and spring pads and no more squeaking

an indy got me like that. I had did my water pump, thermostat, belts and pulleys, oil filter housing gasket, valve cover gasket, and thrust arm bushings. everything came up to about $2800 and I had the car back in about 4-5 hours

what they did was charge me separate for every job even though they basically already had the whole front off.

They never gave at least discount for the labor, like the water, thermostat, belt and pulley are in the same area and tasks. But I think 5 hours to do all those tasks are not less than I expected.