PeachParts Mercedes-Benz Forum - View Single Post - Write up - Ball Joints & Lower Control Arm Bushings & Tool Review (PICS!)

bodyart27 · #1 02-13-2007, 09:40 PM

This is not intended to be a step-by-step guide on replacing the ball joints and lower control arm bushings. It is really a review of some of the tools and tips that can make the job easier as well as inform you of some pitfalls you’ll want to avoid. The effort to assemble this write-up is just payment back to the forum for all the knowledge and coaching this group provides – god knows I “steal shamelessly” off this forum . Also, props to pindelski.com – worth every penny and has a great front end rebuild pictorial.

I’m one of those folks that pour over the forum, the internet and shop manuals to make sure I know what I’m getting into before I tackle a job. Without the aforementioned resources, I wouldn’t have dreamed of tackling rebuilding the front end of my 84 300SD. To bring you up to date on the rebuild, I’ve done upper control arms and sway bushings, an idle arm rebuild kit, the tie rods (about a year ago), and both ends of the brake / guide rod (piece on the lower control arm and the adjustable end piece), and the carrier support bushings as well. So, that leaves only the lower control arm bushings and the ball joints. Search the forum and you’ll find the install of a rebuilt steering box that I did about two years ago. When I started this part of the job (ball joints and lower control arm bushings) I did have one ball boot that is torn (but not dry). You’ll see that one in the pics. The other looked OK but will get replaced as well (it can’t be far behind).

First thing you have to have for a front end rebuild is a press. I picked up this monster Arcan 20 ton shop press from my local Northern Tool store. I think it was $330, but it is MUCH beefier than their $250 20 ton press (the piston is about twice as large for example). Notice in the pic that the press is flanked by Berd Schneider in a CLK DTM racer and Kimi Raikkonen in a McLaren …. but I digress.

Though the Tool Aid ball joint popper is cheap and popular on this forum, it also has a tendency (in my experience) to damage the boot on the joints. Additionally when popping one the joint on the upper control arms it wanted to rotate as I cranked down on the pin – not reassuring under that much stress! Since the upper control arms had been replaced about a month ago, the last thing I wanted to do was damage that boot and have to replace these parts again (pretty pricey parts and very difficult to get to the bolt on the driver’s side under the brake reservoir).

In my quest for a better ball joint popper, I purchased three alternatives from seller “Kinetik Auto Equipment Tools” on eBay. Two models have an arm extending which I thought might be nice as it would provide a counter hold, and thus prevent the rotation I experienced with the Tool Aid popper. They are offered in a 17mm gap and 20mm gap. I found the larger gap to be a close fit on the upper control arm, but I actually ended up using the JTC popper 1916 without the arm. What I liked about this design is that you can spin the tool and adjust the gap (the fulcrum bolt is threaded). It also seemed to “fit” the best on the upper control arm – just a little wiggling and it seats under the boot yet cups the arm well to prevent rotation.

PIC 1 - Aracan Press
PIC 2 - Assortment of "poppers" (black cone is the BMW 3030, long box along bottom is the ball joint tool, across top row in silver - JTC 1916, and the 17mm and 20mm Kinetik poppers with the handles)
PIC 3 - closeup of JTC popper
PIC 4 - demo of spinning fulcrum to increase / decrease gap