Steering Rack Adjustment
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Junior Member
Joined: Jun 2019
Posts: 26
Likes: 2
W220 S320 CDI
Steering Rack Adjustment
I have some free play/dead movement in my steering wheel between about 11:30 and 12:30, which I'm pretty sure is free play in the rack. I also have significant 3 and 6 play only on the passenger wheel that seems like a worn tie rod inner, but as the steering wheel play presents itself when the engine is off and the car stationery, it leads me to believe I have two problems. I am replacing the entirety of the front suspension in the coming days, but I need to determine how much of this steering play is down to the rack.
I've noted that on two or three posts people have had a similar issue and mentioned nipping up a 17mm nut on the rack, which adjusts the preload very slightly with excellent results. I want to try this before sourcing and installing a new rack. However, there is no such 17mm nut on my steering rack. Indeed, none of the steering racks that I've seen pictures of have this 17mm nut either. I don't know if this is something to do with LHD vs RHD. What I do have is a 16mm external torx/star on the pinion housing, and I can just about feel what seem to be measurement grooves on the ring around it. Does this sound like it's the right nut to adjust?
I've noted that on two or three posts people have had a similar issue and mentioned nipping up a 17mm nut on the rack, which adjusts the preload very slightly with excellent results. I want to try this before sourcing and installing a new rack. However, there is no such 17mm nut on my steering rack. Indeed, none of the steering racks that I've seen pictures of have this 17mm nut either. I don't know if this is something to do with LHD vs RHD. What I do have is a 16mm external torx/star on the pinion housing, and I can just about feel what seem to be measurement grooves on the ring around it. Does this sound like it's the right nut to adjust?
Junior Member
Joined: Sep 2021
Posts: 18
Likes: 7
From: Sweden
2004 W220 S500 swb
I have some free play/dead movement in my steering wheel between about 11:30 and 12:30, which I'm pretty sure is free play in the rack. I also have significant 3 and 6 play only on the passenger wheel that seems like a worn tie rod inner, but as the steering wheel play presents itself when the engine is off and the car stationery, it leads me to believe I have two problems. I am replacing the entirety of the front suspension in the coming days, but I need to determine how much of this steering play is down to the rack.
I've noted that on two or three posts people have had a similar issue and mentioned nipping up a 17mm nut on the rack, which adjusts the preload very slightly with excellent results. I want to try this before sourcing and installing a new rack. However, there is no such 17mm nut on my steering rack. Indeed, none of the steering racks that I've seen pictures of have this 17mm nut either. I don't know if this is something to do with LHD vs RHD. What I do have is a 16mm external torx/star on the pinion housing, and I can just about feel what seem to be measurement grooves on the ring around it. Does this sound like it's the right nut to adjust?
I've noted that on two or three posts people have had a similar issue and mentioned nipping up a 17mm nut on the rack, which adjusts the preload very slightly with excellent results. I want to try this before sourcing and installing a new rack. However, there is no such 17mm nut on my steering rack. Indeed, none of the steering racks that I've seen pictures of have this 17mm nut either. I don't know if this is something to do with LHD vs RHD. What I do have is a 16mm external torx/star on the pinion housing, and I can just about feel what seem to be measurement grooves on the ring around it. Does this sound like it's the right nut to adjust?
Hello. I just did this on my S500 the other day (well, my son did help out here).
He turned this 16 mm torxy bolt about a fifth to a quarter turn and then we did another test drive. Before, we could’t keep the car straight when driving about 70 mph but had to correct left-right-left-right all the time, even on completely flat and newly asphalted roads.
After the adjustment, we can easily keep it straight when doing about 100 mph.
Could just be a temp fix, but it is that bolt you can use to adjust.
