front suspension overhaul with Moog

I bought some Moog parts from amazon for the front end of my 525it. It seems there is limited experience on the forums with Moog parts for our E39s, but it's a well respected brand in every other circle I've frequented, so I figured for the price, they were worth a shot. I've had the parts for about a week, but hadn't been able to spend any quality time in the garage because I had to finish a thesis.

I finally got around to starting the job last night, but wasn't able to pop the control arm ball joint or the thrust arm ball joint out of the wheel carrier. I figured the old trick of striking the side of the socket would work, so I wasn't too worried about not having the clothespin type ball joint tool. I also have an assortment of pickling fork, but none of these worked. The closest Harbor Freight is about 20 miles away, so I wanted to avoid that if possible. I stopped at Advance Auto Parts while I was out this morning and used their loaner tool program to borrow the front end tool kit. It had about 5 different tools, including the clothespin type tool. I got it home and figured out that it wouldn't fit because the stud on the ball joint was just a little too long. I took my air-powered cut-off tool and sliced off a portion of the stud. Now the tool worked great. It popped all 4 of them out without a problem after I trimmed the studs.

I did have to perform a little maintenance on the tool first. The threads were little messed up from the previous user, so the first thing I did was run a tap through the threaded portion to clean it up, then I cleaned the bolt with brake cleaner and finally put a little wheel bearing grease on the bolt.

The only snag I had with the Moog parts were the studs on the thrust arms. On the BMW parts, there is a hex head so you can hold the stud in place while you tighten the nut. There is no hex on the Moog thrust arms, but there is on the control arms. Not sure why they couldn't continue that. I overcame this by using a prybar between the top of the thrust arm and the bottom of the strut. I applied some force to the top of the thrust arm, forcing it down in the hole. Then I ran the nut on with my impact gun, then loosened slightly so I could torque it properly with the torque wrench.

I still have to install the sway bar end link on one side and do the final torque for the thrust arm bushing nut and the control arm bushing nut .

For the record, it is not necessary to remove the rotor. I'm not sure if it's necessary to remove the caliper, but I did and I think it gives you a little more room to work. I have about 6 hours into the job up to this point, but I'd say the second side went much faster than the first. I also wasn't trying to rush. I took my time and enjoyed the process.

It would certainly be more efficient to replace struts at the same time, so if you're thinking you want to do this and the struts, gather all the parts and do it. For me, I'm trying to spread the expense out over some months.

So this has been my experience in a nutshell.

Don't forget to load the suspension before torquing the bushing bolts. Otherwise you'll tear them up when you drive. Cutting the ball joint bolts definitely makes removing them easier, especially when using the HF tool.

Originally Posted by Fudman

Don't forget to load the suspension before torquing the bushing bolts. Otherwise you'll tear them up when you drive. Cutting the ball joint bolts definitely makes removing them easier, especially when using the HF tool.

Yeah good point Fudman. I haven't torqued the bushing bolts for either the control arm or the thrust arm yet. It's always worth repeating.

I really just wanted to get the point out about the Moog parts and the Advance Auto Parts loaner tool.

As to the missing hex, In most cases if the hex is missing there are 2 flat sides at the very base of the stud that you can put a wrench on to hold it, Most of the time the top of the boot is hiding it. It would be very strange to not have one or the other.

Max

Fudman
How would one load a suspension when installing these parts? Which parts require loading when installed?
Thanks

Originally Posted by King540i

Fudman
How would one load a suspension when installing these parts? Which parts require loading when installed?
Thanks

Look here:
http://www.beisansystems.com/procedu..._procedure.htm

Lift wheel carrier to position of "empty weight position" or "normal position" as previously measured (tape measure).
Utilize lift (jack and towel) to lift up on swing arm at its lowest point; found adjacent to wheel carrier inboard side at ball joint.

Or, you can drive the car on to some ramps, and torque everything down from there...

The beisan approach works nicely. I put my car onto 2"X10" jack pads, 4 plies thick (6"), under each tire. This kept the weight evenly distributed on all corners and gave me enough room to torque the bushing bolts. I use these jack pads whenever I need to work under my car (like ATF change).

I finished everything up tonight and took her for a little drive. WOW! The steering wheel is ROCK SOLID at 70+ mph. Fan-effing-tastic!