MK5 Golf GTI

All Things Mk5 => Mk5 General Area => Topic started by: MikeBee on July 03, 2017, 09:53:57 am

Title: Rear Top Mount Knocking
Post by: MikeBee on July 03, 2017, 09:53:57 am
Hi All,

I've got a knocking from the rear of my Edition 30. Initially I thought it was the hatch not closing properly but I've adjusted the stops for the hatch and it's now nice and solid. Trim is all solid, so I started checking suspension bits. Droplinks all ok, bushes look fine. The one bit that looks super dodgy is that I can wiggle the top of the damper strut on each side and there is a load of play.

It looks pretty easy to replace the rear top mounts, but do I need a new top mount and a new bump stop or do I just get a new bump stop and replace the old one? And are there any uprated parts that I should consider (TT-S, S3 etc)?

Thanks!
Title: Re: Rear Top Mount Knocking
Post by: pudding on July 03, 2017, 10:56:28 am
Rear top mounts rarely go on these cars.  Is the play between the damper rod and damper body, or between the damper rod and the top mount?   New mounts for the rear are quite expensive, I think around £50 each when I did mine, and yeah, they are easy to fit.  Just be careful you don't cross thread the 2 bolts as they are at an angle.
Title: Re: Rear Top Mount Knocking
Post by: AJP on July 03, 2017, 11:56:06 am
Interested in this. Like we discussed, Pudding, I recently got a tiny knock at the rear after fitting a new set of coilovers.

I went through the usual checks - something loose in the spare wheel well, adjusted the boot rubbers etc - and it's still there.

I initially thought that the firmer spring and damper of the coilovers was causing something loose to make enough noise to notice, and that the softer previous setup didn't highlight it. But now I'm not so sure.

I didn't replace the rear top mounts like I did the fronts as I assumed the same as what Pudding is saying - there doesn't seem to be much to go wrong.

I need to get under for a proper look really!
Title: Re: Rear Top Mount Knocking
Post by: MikeBee on July 03, 2017, 12:21:29 pm
Cool thanks for the reply. I hadn't considered the damper rod and the damper body itself, but it's possible. I only grabbed the damper body and wiggled it.

I will double check.
Title: Re: Rear Top Mount Knocking
Post by: pudding on July 03, 2017, 12:28:33 pm
I did my rear top mounts a couple of months ago when I threw all the VWR stuff on.   At 110K miles, the rear top mounts showed zero wear!

Did you chop down the rear bumpstops the same amount as you lowered the car by, or did you leave them factory length?

Did you check the rear drop links and ARB bushes etc?  Uprated suspension puts extra strain on some of the components.

These cars are just noisy over bumps anyway.  The rear top mounts are TINY and 90% metal! The front mounts are somewhat lacking in the rubber department compared to the previous generation as well, but it's partly why the MK5 platform handles well. Less squidge.  I get a slight knock from the back only on cobbled streets and block paved roads, but I just put it down to the nature of the beast! It could just be damper noise.  The VWR dampers are noisier than the OEM ones, but it's not really that noticeable unless you listen hard for it.
Title: Re: Rear Top Mount Knocking
Post by: pudding on July 03, 2017, 12:29:22 pm
Cool thanks for the reply. I hadn't considered the damper rod and the damper body itself, but it's possible. I only grabbed the damper body and wiggled it.

I will double check.

Yeah my gut instinct was damper knock.....which is the damper itself rather than any of it's mounting hardware.
Title: Re: Rear Top Mount Knocking
Post by: AJP on July 03, 2017, 12:44:44 pm
@Pudding If I remember correctly from having a nosey in the box before I had them fitted, the Vogtland rear dampers come with their own bumpstops and dustshields. So just pull out all the old and replace with new. No trimming needed, in theory.

Incidentally, the knock is just how you describe it over cobbled streets etc, at low speed. I'm inclined not to worry too much as it all works rather well for a budget kit - with no funny noises - once up past 20mph or so.
Title: Re: Rear Top Mount Knocking
Post by: pudding on July 03, 2017, 01:55:27 pm
Sounds normal to me mate.  And you've just reminded me actually..... I was in the back of a brand new Tiguan over the weekend, and guess what.....knocking from the back over bumps!  Those things have a surprisingly stiff/harsh ride for a soft roader.

I think it's just damper noise and because top mounts are so small/stiff on German cars, it comes through to the cabin as a knock.
Title: Re: Rear Top Mount Knocking
Post by: AJP on July 03, 2017, 06:52:21 pm
Yeah it's not keeping me awake!

What might though, is a new 'mystery creak' that I just can't work out. It happens when pulling out of or into a parking spot - so could be caused by any number of things like steering, clutch etc.

It's gone before I get the chance to pinpoint where it's coming from, but it sounds close, almost like it's coming from the interior. But I have a feeling it's just being efficiently transmitted into the cabin. Possibly front top mounts, but it's too 'shrill' a noise, and also they're only a few months old. Rack? Hmmm. Hope not.

It's hard to describe in terms of how it sounds.

It's hard to pinpoint in terms of location.

It's hard to replicate.

God damn.
Title: Re: Rear Top Mount Knocking
Post by: AJP on July 03, 2017, 06:54:29 pm
Sorry to hijack your thread by the way @MikeBee!
Title: Re: Rear Top Mount Knocking
Post by: MikeBee on July 03, 2017, 08:46:20 pm
Sorry to hijack your thread by the way @MikeBee (http://www.mk5golfgti.co.uk/forum/index.php?action=profile;u=18011)!

Haha no worries!
Title: Re: Rear Top Mount Knocking
Post by: pudding on July 04, 2017, 09:28:19 am
Lol, maybe we need a super thread entitled "Strange noises and possible causes"  :grin:

@AJP (http://www.mk5golfgti.co.uk/forum/index.php?action=profile;u=11926) that's a weird one for sure.  Only does it during steering, and I'm guessing quite a lot of lock angle?
Title: Re: Rear Top Mount Knocking
Post by: AJP on July 04, 2017, 10:45:13 am
Lol, maybe we need a super thread entitled "Strange noises and possible causes"  :grin:

@AJP (http://www.mk5golfgti.co.uk/forum/index.php?action=profile;u=11926) that's a weird one for sure.  Only does it during steering, and I'm guessing quite a lot of lock angle?
I couldn't tell you for sure whether it's steering (and how much), or drivetrain, or something else. But it happens as I'm setting off from stationary.

I'll keep an ear out for it today and report back if I suss it!
Title: Re: Rear Top Mount Knocking
Post by: MikeBee on July 04, 2017, 01:21:39 pm
So disappointingly I had my MOT today and asked the tester to check out the dampers and top mounts at the rear. Nothing wrong...

Back to the drawing board  :confused:
Title: Re: Rear Top Mount Knocking
Post by: pudding on July 04, 2017, 01:31:01 pm
I think MOT tests only fail the dampers if they are leaking.  Any oil spotting on yours?

Time to get it on the ramp and give everything a good hard whack.  Some worn parts that aren't physically loose to the touch can sometimes reveal themselves if you hit the tyre hard with a hammer, which simulates the behavior of driving over bumps.
Title: Re: Rear Top Mount Knocking
Post by: MikeBee on July 04, 2017, 01:33:29 pm
Yeah good shout.

Dampers weren't leaking and had no oil passing the seal. I asked him specifically to check the dampers and top mounts, but giving them a whack is a good idea.
Title: Re: Rear Top Mount Knocking
Post by: pudding on July 04, 2017, 01:42:45 pm
Won't hurt to try it.  I've isolated worn ball joints and drop links that way in the past, and a worn steering rack!   None of said parts were loose when levering on them.
Title: Re: Rear Top Mount Knocking
Post by: Bodyboarder81 on April 16, 2018, 05:13:23 pm
Hi .... just bumping (  :signLOL:) this thread

Just had the ohlins suspension fitted ..... I’m getting a light knocking sound from the rear over speed bumps and at speed .Doesnt seem to happen when the cars up to speed ( or I can’t hear it ) . I also didn’t replace the rear top mounts and thinking I should have , along with the rear drop links .... any other suggestions?

Yours do this @Pudding (http://www.mk5golfgti.co.uk/forum/index.php?action=profile;u=10733) ?
Title: Re: Rear Top Mount Knocking
Post by: pudding on April 16, 2018, 09:27:02 pm
Mine has knocked at the rear with standard, Racingline and Ohlins  :grin:

It only does it on cobbled streets or block paved roads really. I replaced the rear top mounts. Last MOT I had there was an advisory on some worn bushes, so could be that. You lose the rubber spring pads with the ohlins, so they might be a bit noisier.
It’s solid in the corners so the noise doesn’t bother me really.  A full rebush is on the to-do list!
Title: Re: Rear Top Mount Knocking
Post by: Tazocin on April 17, 2018, 09:28:41 am
When I fitted my B14s all round I got some degree of knock over the first 500 or so miles. Always at low speed at left rear and offside front and tricky to reliably reproduce, it drove me crazy! I had the car up on  stands every other day checking nothing was loose or worn, I replaced the rear droplinks, I checked torque on all my work over and over but could not find the cause. Then, after that initial distance it all settled down. I had to assume it was the coilovers/car adjusting to a new ride position and it just needed 'bedding in' time.

Not to say there isn't something wrong but if you are asking a frame thats sat in one position for 8 or more years to then sit in a slightly new one I think a period of settling in is required. The other thing to note is, as Pudding mentioned, new ride height will adjust the strain on arb and droplinks etc so they might not appear or feel loose but actually are worn.
Title: Re: Rear Top Mount Knocking
Post by: Bodyboarder81 on April 17, 2018, 11:14:46 am
Thanks for the replies  :happy2:

The cars been running on a few different suspension setups ... but only done this while on the new setup ( ohlins ) I think it’s due to the higher spring rate that these coilovers use , maybe have highlighted a issue . I’ll see what happens over the next few weeks and I might even put some new drop links on anyway to rule it out .
Title: Re: Rear Top Mount Knocking
Post by: pudding on April 20, 2018, 10:51:54 am
How you getting on mate?

I backed off the damping on mine today (10 clicks open front, 12 clicks open rear) and the noise from the rear has reduced considerably.  On mine it's more of a rumble / pattering noise than a well defined clunk.  I have read that much stiffer aftermarket dampers are notorious for transmitting noise into the cabin on these cars, so it's probably just damper noise assuming nothing is worn out back there.
Title: Re: Rear Top Mount Knocking
Post by: Bodyboarder81 on April 20, 2018, 04:10:11 pm
How you getting on mate?

I backed off the damping on mine today (10 clicks open front, 12 clicks open rear) and the noise from the rear has reduced considerably.  On mine it's more of a rumble / pattering noise than a well defined clunk.  I have read that much stiffer aftermarket dampers are notorious for transmitting noise into the cabin on these cars, so it's probably just damper noise assuming nothing is worn out back there.

Hi dude ..... it’s an odd one . I’m only getting the noise from one side ( passenger rear)  so we went back over everything and all was spot on ... checked all bush’s , links ect ... all absolutely fine . The only thing We could find is on that side the rear caliper carrier has a lot of play .... like you can really move it by hand and when you whack  the tyre ( when off the ground ) it’s making quite a noise . So I’ve ordered a new carrier /sliding pins and swop that out . See what’s what after that . I have mine set at 11 clicks open ( bearing in mind I have eibach arbs ) I might try to back the dampers off and see if that’s the cause of the light knock .  :happy2:

All this aside though ...... holy baby mother of king king they are good ... like REALLY good . You just don’t need anymore power with the way it can go round corners ! Love it  :drinking:
Title: Re: Rear Top Mount Knocking
Post by: pudding on April 21, 2018, 12:03:56 pm
How you getting on mate?

I backed off the damping on mine today (10 clicks open front, 12 clicks open rear) and the noise from the rear has reduced considerably.  On mine it's more of a rumble / pattering noise than a well defined clunk.  I have read that much stiffer aftermarket dampers are notorious for transmitting noise into the cabin on these cars, so it's probably just damper noise assuming nothing is worn out back there.

Hi dude ..... it’s an odd one . I’m only getting the noise from one side ( passenger rear)  so we went back over everything and all was spot on ... checked all bush’s , links ect ... all absolutely fine . The only thing We could find is on that side the rear caliper carrier has a lot of play .... like you can really move it by hand and when you whack  the tyre ( when off the ground ) it’s making quite a noise . So I’ve ordered a new carrier /sliding pins and swop that out . See what’s what after that . I have mine set at 11 clicks open ( bearing in mind I have eibach arbs ) I might try to back the dampers off and see if that’s the cause of the light knock .  :happy2:

All this aside though ...... holy baby mother of king king they are good ... like REALLY good . You just don’t need anymore power with the way it can go round corners ! Love it  :drinking:

It's probably the caliper then mate.  Mine are quiet  :happy2:   Whacking the tyre with a hammer is a great way to trace knocks  :happy2:

I knew you'd like them  :happy2:  They are easily the best ride quality / handling compromise I have yet experienced.  With my damper settings, they feel as soft as OEM when cruising about, but none of the OEM wallowing or body roll when giving it the beans.  Awesome stuff  :smiley:
Title: Re: Rear Top Mount Knocking
Post by: Bodyboarder81 on April 21, 2018, 02:29:58 pm
How you getting on mate?

I backed off the damping on mine today (10 clicks open front, 12 clicks open rear) and the noise from the rear has reduced considerably.  On mine it's more of a rumble / pattering noise than a well defined clunk.  I have read that much stiffer aftermarket dampers are notorious for transmitting noise into the cabin on these cars, so it's probably just damper noise assuming nothing is worn out back there.

Hi dude ..... it’s an odd one . I’m only getting the noise from one side ( passenger rear)  so we went back over everything and all was spot on ... checked all bush’s , links ect ... all absolutely fine . The only thing We could find is on that side the rear caliper carrier has a lot of play .... like you can really move it by hand and when you whack  the tyre ( when off the ground ) it’s making quite a noise . So I’ve ordered a new carrier /sliding pins and swop that out . See what’s what after that . I have mine set at 11 clicks open ( bearing in mind I have eibach arbs ) I might try to back the dampers off and see if that’s the cause of the light knock .  :happy2:

All this aside though ...... holy baby mother of king king they are good ... like REALLY good . You just don’t need anymore power with the way it can go round corners ! Love it  :drinking:

It's probably the caliper then mate.  Mine are quiet  :happy2:   Whacking the tyre with a hammer is a great way to trace knocks  :happy2:

I knew you'd like them  :happy2:  They are easily the best ride quality / handling compromise I have yet experienced.  With my damper settings, they feel as soft as OEM when cruising about, but none of the OEM wallowing or body roll when giving it the beans.  Awesome stuff  :smiley:

Adjusted the dampers to a little softer ... but same noise from the passenger rear . Picked up carrier from ecp ( genuine mk5 r32 one in blue ) for the cheap price of £90 . Will probably get around to it on Monday ( we’ll i say me ... I mean my friend will at the garage  :ashamed:) the new carrier has zero play ... so I’m confident this is it . Never heard of a worn carrier before ? Very odd .