DIY Notes - Strut/Shock Replacement, Suspension Refresh
#1
Junior Member
Thread Starter
DIY Notes - Strut/Shock Replacement, Suspension Refresh
I recently replaced the front struts and rear shock absorbers on my 2005 C55 AMG. While I was at it, I replaced all the front suspension wear items to include strut bearings, bumpers, sway bar links, inner and outer tie rod ends, steering rack bushings, tie rod boots, lower control arms, and torque struts. I used all OE vendor parts with the exception of the struts and shocks which are Bilstein Sport type (B8). Before the refresh, my car had 52,000 miles, vague steering, and particularly unpleasant ride quality over ridges and road divots.
I performed this work in a home garage using a floor jack and substantial jack stands. Specialty tools included E Torx sockets, Hex sockets, and Torx bits. I had the good fortune of access to a second car so I was in no hurry. Despite concerns, when I was finished, the front end was straight enough for a non-white knuckle drive to the alignment shop.
The end result is a big and worthwhile increase in steering feel and accuracy, a big reduction in "crashiness" over bumps, and a general increase in ride plushness ( though I would still consider the ride relatively poor quality, a deficit noted when the C55 was new).
Work Notes;
Parts Notes (I am not affiliated in any way with the vendors)
Tool Notes; (I am not affiliated in any way with the vendors)
Sway Bar Link to Strut - T40 Bit and 19mm wrench
Strut to Upper Steering Knuckle - E18 socket and 21mm socket
Upper Strut Mount - 7mm Hex and 21mm wrench
Prying out Strut Bumper
Here you can see the offset of the fluted bolt in the control arm - you should note this for re-assembly
Original AMG Front Spring for reference
Original Strut for reference
Finished front suspension
Trunk lining removed to expose left rear shock upper mount.
Jack placed under differential carrier
I performed this work in a home garage using a floor jack and substantial jack stands. Specialty tools included E Torx sockets, Hex sockets, and Torx bits. I had the good fortune of access to a second car so I was in no hurry. Despite concerns, when I was finished, the front end was straight enough for a non-white knuckle drive to the alignment shop.
The end result is a big and worthwhile increase in steering feel and accuracy, a big reduction in "crashiness" over bumps, and a general increase in ride plushness ( though I would still consider the ride relatively poor quality, a deficit noted when the C55 was new).
Work Notes;
- When undoing control arms, try to note the position of the fluted bolt (if so equipped) There are three positions and this will allow you to put the suspension back with the same alignment settings. Similarly, when loosening the bolts, loosen the nut rather than the bolt. If the bolt is fluted and is in an offset position, turning the bolt can break the splines inside the control arm bushing.
- When loosening the strut top nut and the strut to knuckle nut using a Torx bit or Hex bit, make sure you apply torque to the wrench and not the holding Torx or Hex bit or you will end up with broken bits. It's probably an obvious note but useful for first timers.
- The inner tie rod ends are not that scary to do. I used large Channel Lock pliers to grip the 41mm flats and was able to break them loose without any drama. Some online briefs show specialty tools and techniques but for the C55 these are not really necessary. Once you have removed the boots (you will need replacement boots and clamps and optionally a clamp tool if you go with OE style clamps) you will see that it is pretty straightforward.
- The same goes for the steering rack bushings. Mine popped right out above and below and as long as your hands are not XXXL you will be able to get in there and put the new ones in.
- I took my old struts with springs on to a shop to have the new struts installed and paid a nominal fee for the service. There is a small cost offset here in that you will not need to purchase the specialty nut tool.
- Regarding jacking the rear of the car, I placed wood blocks under the differential carrier in front of the AMG heat sink and it worked fine (see picture).
- To save yourself a bit of wrestling, you may want to wire the rear shocks in a compressed position to ease removal. The same goes for installing the new ones.
- Finally, I used the technique of jacking the suspension to approximate normal ride height (eyeballing that tie rods are level) before torquing the lower control arm bushings.
Parts Notes (I am not affiliated in any way with the vendors)
- Struts - Bilstein Sport B8 - (* bump stop built in)
- Strut Bearing - 2033200273 (2 required)
- Strut Bumper - 2033220344 (2 needed)
- Shocks - Bilstein Sport B8
- Lower Control Arm - Lemforder - 2043304311 (LH) 2043304411 (RH) - (* one-time use nuts not included - see nut p/n below)
- Hardware Kit for Strut Install - 2033200056 - (2 required)
- Torque Strut - Lemforder - 2043301911 (LH), 2043302011 (RH)
- Steering Rack Bushing - 2033330514 (4 required)
- Tie Rod Inner - Lemforder - 2303380015 (same for LH and RH - 2 required)
- Tie Rod Outer - Lemforder - 2033303903 (LH), 2033304003 (RH)
- Steering Rack Boot - Lemforder - 2034630296 (2 required) - (* may need clamps and O ring if not in kit)
- Sway Bar Link - Lemforder - 2033202989 (2 required)
- Nut for control arm, torque strut, strut top, strut to knuckle - 2029900851 (at least 4 needed with control arm replacement)
Tool Notes; (I am not affiliated in any way with the vendors)
- Boot Clamp Tool - Lisle 30600 Offset Boot Clamp Plier - for replacing steering rack boot clamp
- GearWrench 3916D - for separating outer tie rod end ball joint
- Wrench and socket sizes - T40, E18, 21mm, 19mm, 17mm, 7mm Hex Bit
Sway Bar Link to Strut - T40 Bit and 19mm wrench
Strut to Upper Steering Knuckle - E18 socket and 21mm socket
Upper Strut Mount - 7mm Hex and 21mm wrench
Prying out Strut Bumper
Here you can see the offset of the fluted bolt in the control arm - you should note this for re-assembly
Original AMG Front Spring for reference
Original Strut for reference
Finished front suspension
Trunk lining removed to expose left rear shock upper mount.
Jack placed under differential carrier
#3
excellent contribution!
#4
Member
Clarification please: I don't see any mention of aftermarket lowering springs here. Did you use the B8 strut with the OEM springs? Have you had any problems with the shorter length of the B8's over the OEM struts? (Yes, I've searched all over for the answers, but nearly all other posters are using shorter springs with the B8).
Thanks!
Naugamanator
Thanks!
Naugamanator
#5
Senior Member
My question as well. I thought the B6 Bilsteins were for stock springs and the B8's are for shortened springs. Asked a different way, are the stock AMG springs considered "short" compared with a non AMG model?
#6
Junior Member
Thread Starter
Guys, I used stock springs front and back - no ill effects noted in operation yet. In another thread, a poster noted that Bilstein specified this model for a stock C55.