front knocking noise
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2008 GL320CDI (310k), 2017 GLS450 (170k), 2024 Sprinter 2500 (40k)
front knocking noise
It sounds like worn out sway bar links, but I replaced those couple of months ago, so it is not that. Issue started 2-3 weeks after I replaced those. I also feel it in the steering wheel. Replaced both tie rod ends and problem still exists. What should I check next?
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From: Allentown, PA
'08 GL 320 CDI
Don't count out the sway bar end links just because they were replaced recently. Check them out - especially if they are cheapies. I'm relatively new to this GL320, but it seems like end links are a pretty common thing to wear out quickly. But hey, I'll take that (easy, cheap) over something else!
I even had a knocking that we swore wasn't the end link - I couldn't manually make it make noise with the car in the air, neither could my shop. But everything else checked out so they made an educated guess and replaced it... yup, it was bad.
I also have a very small, occasional knocking noise that sounds more like it's from the the steering wheel shaft, down low (and can feel it). They checked that out and said there was an issue with it (not safety related), but to wait until it's more obvious so they can fix it under warranty.
I even had a knocking that we swore wasn't the end link - I couldn't manually make it make noise with the car in the air, neither could my shop. But everything else checked out so they made an educated guess and replaced it... yup, it was bad.
I also have a very small, occasional knocking noise that sounds more like it's from the the steering wheel shaft, down low (and can feel it). They checked that out and said there was an issue with it (not safety related), but to wait until it's more obvious so they can fix it under warranty.
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2008 GL320CDI (310k), 2017 GLS450 (170k), 2024 Sprinter 2500 (40k)
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From: Allentown, PA
'08 GL 320 CDI
I'm wondering that, too. Considering even the OEM's go out kind quick, I wonder if it's worth it? I dunno. 
I've got one Vaico brand on there (it's what the inspection shop had in stock) and another brand on the other side... I forget the name - sounded kinda German and I recognized it, but I forget. All within a couple months of each other. Next time, if I can plan ahead, I'll try Lemfoerder.
I've got one Vaico brand on there (it's what the inspection shop had in stock) and another brand on the other side... I forget the name - sounded kinda German and I recognized it, but I forget. All within a couple months of each other. Next time, if I can plan ahead, I'll try Lemfoerder.
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2008 GL320CDI (310k), 2017 GLS450 (170k), 2024 Sprinter 2500 (40k)
Two of my non-oem sets lasted 12-16 months. But with this oem set I'm loosing faith. I suppose I could get another set to see if it fixes current issue. If it does not, I'll keep it till I need to replace them. I still don't know how to explain the fact that I can hear and feel knocking on my steering wheel.
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From: Allentown, PA
'08 GL 320 CDI
ALX, do you happen to know who makes the OEM set?
A2J, I can't tell you exactly what they did to diagnose the small clicking noise/feeling I have once in awhile in my steering wheel. But I can tell you that it didn't take them that long to diagnose it. All I remember on that is that it was something down low on the steering wheel shaft (although I could be using the wrong term there).
Some things I'm very comfortable doing myself, but I have never ventured into this before so I let them do it. If it's not something you're comfortable with, it might be worth it to let a shop take a look.
A2J, I can't tell you exactly what they did to diagnose the small clicking noise/feeling I have once in awhile in my steering wheel. But I can tell you that it didn't take them that long to diagnose it. All I remember on that is that it was something down low on the steering wheel shaft (although I could be using the wrong term there).
Some things I'm very comfortable doing myself, but I have never ventured into this before so I let them do it. If it's not something you're comfortable with, it might be worth it to let a shop take a look.
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Thread Starter
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2008 GL320CDI (310k), 2017 GLS450 (170k), 2024 Sprinter 2500 (40k)
I might have two different issues here. The steering issue concerns me most. I also forgot to mentioned that when I quickly turn the steering wheel, while stationary, I hear and feel a knock sound. Steering does not feel loose or any different than before. But it feels like it is hitting metal on metal.
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From: Allentown, PA
'08 GL 320 CDI
I might have two different issues here. The steering issue concerns me most. I also forgot to mentioned that when I quickly turn the steering wheel, while stationary, I hear and feel a knock sound. Steering does not feel loose or any different than before. But it feels like it is hitting metal on metal.
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2008 GL320CDI (310k), 2017 GLS450 (170k), 2024 Sprinter 2500 (40k)
Discovered the cause of the steering knock. Driver side bushing on the steering rack.
Did anyone replace those? Quick search shows 2-piece bushing per side. Sold in sets of 4, for both sides.
Did anyone replace those? Quick search shows 2-piece bushing per side. Sold in sets of 4, for both sides.
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From: Espoo, Finland
2012 GL 350
I've got a similar knocking sound that didn't go away with replacement of the anti-roll bar end links (I used Lemforder...) and it's making me nuts. Before the car was out of warranty I took it to the dealer and they said they couldn't hear it. I can hear the noise with punk rock at full volume, so maybe they need their hearing checked.
Do you have part numbers for these so I can locate them and check them out on my vehicle please?
Do you have part numbers for these so I can locate them and check them out on my vehicle please?
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2008 GL320CDI (310k), 2017 GLS450 (170k), 2024 Sprinter 2500 (40k)
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Joined: May 2013
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From: Espoo, Finland
2012 GL 350
So I got under the vehicle today and found the bushings you show in the photo. I put a pry bar on the rack and can't get it to play at all, but the noise is just as you describe as is the feeling in the steering wheel. I'm only at 53k miles...
Anyway, my 3 year old was "helping" and I didn't put it on the lift so was just laying on my back, but it appears that the front diff is in the way of the bolt that you need to remove to swap the driver's side out. Can you explain how you did this? My only thought was that perhaps the bolt will clear the subframe hole if I push it through as far back as it will go, and then if I unbolt both the drivers and passenger side, then perhaps I can move the rack enough to pull the bolt and swap out the bushings.
My driver's side bushings are oil soaked like those in your photos, but the passenger side are dry.
Anyway, my 3 year old was "helping" and I didn't put it on the lift so was just laying on my back, but it appears that the front diff is in the way of the bolt that you need to remove to swap the driver's side out. Can you explain how you did this? My only thought was that perhaps the bolt will clear the subframe hole if I push it through as far back as it will go, and then if I unbolt both the drivers and passenger side, then perhaps I can move the rack enough to pull the bolt and swap out the bushings.
My driver's side bushings are oil soaked like those in your photos, but the passenger side are dry.
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2008 GL320CDI (310k), 2017 GLS450 (170k), 2024 Sprinter 2500 (40k)
At the first glance I thought there no way this was going be easy. So I removed nuts from both sides, removed mounting bolts (3) for the front diff and disconnected toe rod ends. This allowed some movement of both, steering rack and front diff. Driver side bushing were so worn out that bolt and bushings came out easy. I put the bolt the other way in for the next time I have to do it. Something is telling me that I'll have to do it again in 80-100k miles. Passenger side was good, but I replaced it anyway because I was already there. It only took extra 2 mins. Vehicle's front wheels were on ramps and I don't think I even bothered with raising it. So I thought this whole deal will take a day or two, but after 30 mins realized that I'm almost done. It took me about an hour.
I think the oil is the cause of the bushing failure. I think it's the steering rack that's leaking, but not big of a leak to notice unless you look in that area.
I think the oil is the cause of the bushing failure. I think it's the steering rack that's leaking, but not big of a leak to notice unless you look in that area.
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Joined: Jan 2020
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2008 ML320 CDI
Rack bushings beat me
At the first glance I thought there no way this was going be easy. So I removed nuts from both sides, removed mounting bolts (3) for the front diff and disconnected toe rod ends. This allowed some movement of both, steering rack and front diff. Driver side bushing were so worn out that bolt and bushings came out easy. I put the bolt the other way in for the next time I have to do it. Something is telling me that I'll have to do it again in 80-100k miles. Passenger side was good, but I replaced it anyway because I was already there. It only took extra 2 mins. Vehicle's front wheels were on ramps and I don't think I even bothered with raising it. So I thought this whole deal will take a day or two, but after 30 mins realized that I'm almost done. It took me about an hour.
I think the oil is the cause of the bushing failure. I think it's the steering rack that's leaking, but not big of a leak to notice unless you look in that area.
I think the oil is the cause of the bushing failure. I think it's the steering rack that's leaking, but not big of a leak to notice unless you look in that area.
I love this vehicle's safety, comfort features and mileage, but I'm very frustrated with the engineering, from a maintenance and repair POV. I get the feeling that the engineers put maintainability as the *very last* concern on the list of things to optimize for. Having had to do the dreaded o-ring replacement on the oil cooler (buried in the valley of the V-8, not mounted on the front, where every other one is mounted), I've gotten to know a lot about wrenching on these vehicles and I'm certainly developing a love-hate relationship with mine. My old e300d had it's quirks (glow plugs come to mind), but these cars feel like they're made to be disposable, not repaired nor even maintained. The "lifetime" oil in the transmission is a good example of this mentality.
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From: Emmett, ID, USA
2007 GL450
I had very rapid onset clunking in the front suspension, following swaybar end link replacement. It turned out one mounting nut had simply loosened.
I ordered some M14 washers (stainless just because), hoping that a cleaner seating area for the nut will help reduce the tendency to wander loose. The hole in the swaybar end is significantly larger than the shaft.
I ordered some M14 washers (stainless just because), hoping that a cleaner seating area for the nut will help reduce the tendency to wander loose. The hole in the swaybar end is significantly larger than the shaft.
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From: Allentown, PA
'08 GL 320 CDI
I had very rapid onset clunking in the front suspension, following swaybar end link replacement. It turned out one mounting nut had simply loosened.
I ordered some M14 washers (stainless just because), hoping that a cleaner seating area for the nut will help reduce the tendency to wander loose. The hole in the swaybar end is significantly larger than the shaft.
I ordered some M14 washers (stainless just because), hoping that a cleaner seating area for the nut will help reduce the tendency to wander loose. The hole in the swaybar end is significantly larger than the shaft.
Also, you might consider using a nyloc nut... or use some blue loctite on your existing nut... or stick a couple pieces of fishing line over the threads as you tighten the nut down (making a "locking" nut).
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From: Emmett, ID, USA
2007 GL450
Eric, the hole that the shaft of the end link goes through should not be noticeably larger than the shaft. It should be "just" large enough to get the shaft through - almost "snug". Either you have the wrong end link in there or because the nut wasn't tightened up enough and loosened, it allowed the hole to wallow over time from the leverage of the end link going up and down. Just an fyi.
Also, you might consider using a nyloc nut... or use some blue loctite on your existing nut... or stick a couple pieces of fishing line over the threads as you tighten the nut down (making a "locking" nut).
Also, you might consider using a nyloc nut... or use some blue loctite on your existing nut... or stick a couple pieces of fishing line over the threads as you tighten the nut down (making a "locking" nut).
It's possible the installed links are not at spec. They have a flat on the bolt instead of the torx end.
The nuts are Nyloc. I don't understand what's happening here.
