Jump to content
OnlyAfro

Front Suspension Knock

Recommended Posts

I've got a knock coming from the front right.

 

Description:

  • Only present at low speeds (<30mph) and worse the slower you go
  • Only occurs with sudden jolts (hitting speed bumps / large pot holes / driving over cat's eyes)
  • Single clunk when it happens (per bump)
  • No steering judder or jerking
  • Braking whilst hitting the bump seems to prevent the knock

 

Factors:

  • Front lower lateral and compression arms have just been replaced (with ebay arms) on left and right and the knock was present immediately after, but the left side is fine
  • Replacing these arms involved disconnection of the drop links, shocks, tie rods and cross brace
  • The nut on the right side compression arm was seized and had to be chiselled off violently, sending shocks through the rest of the suspension that could have caused something else to fatigue(?)
  • Car and suspension (other than lower arms and tie rods) are 12 years old

 

Step taken:

  • Nuts checked several times  to ensure they are torqued
  • Pry bar used on components to check for play to no avail (not really managed to check shock with it though)
  • Car bounced (hung off the front ARB and yanked repeatedly with entire body weight), but didn't produce a knock

 

Thoughts

  • Perhaps a worn shock or top mount, not sure if that would only knock at low speed though?
  • Ball joint could be faulty in new compression arm that was installed, but can't recreate with pry bar
  • Drop links are often suggested, but they usually chatter constantly rather than producing a single large clunk (will try drive with them disconnected at the weekend to rule them out though)
  • Perhaps brake related, but no idea what it would be

 

Any suggestions?

 

Thanks

Share this post


Link to post
Share on other sites

Banana arm ball joint.  Just done mine with exact same symptoms, tried everything to diagnose inc pry bar etc.  Just because you have replaced recently doesn't mean it's good, mine was less than a year old and sub 500 miles.  Get a mate to hold the arm near the ball joint  and with handbrake off grab opposite wheel spokes and jolt down, your mate will feel it.

Share this post


Link to post
Share on other sites

Wrong size of seating cone fitted to new lateral arm.

 

Or suspension upright lower ball joint failure, however I would be firstly looking at the seating cone.

Share this post


Link to post
Share on other sites
7 minutes ago, ZMANALEX said:

Wrong size of seating cone fitted to new lateral arm.

 

Or suspension upright lower ball joint failure, however I would be firstly looking at the seating cone.

Seating cone is the same.

 

I still have the old arm, so I can swap it back in to test.

 

Any reason you suggest lateral arm over compression arm?

Share this post


Link to post
Share on other sites
5 minutes ago, OnlyAfro said:

Seating cone is the same.

 

I still have the old arm, so I can swap it back in to test.

 

Any reason you suggest lateral arm over compression arm?

Did you replace the compression rod and also the lower lateral arm (track control arm)?

Share this post


Link to post
Share on other sites
1 minute ago, ZMANALEX said:

Did you replace the compression rod and also the lower lateral arm (track control arm)?

image.png.57b6f9605cd8445e69f346a7232dfe8f.png

Replaced compression rods (red) and transverse links (blue), both left and right side.

 

Bushes were worn in both, but not faulty or knocking. Old transverse link is still in acceptable condition, but old compression rod was destroyed (ballpoint thread bashed up and bush ripped out).

Share this post


Link to post
Share on other sites
3 minutes ago, OnlyAfro said:

image.png.57b6f9605cd8445e69f346a7232dfe8f.png

Replaced compression rods (red) and transverse links (blue), both left and right side.

 

Bushes were worn in both, but not faulty or knocking. Old transverse link is still in acceptable condition, but old compression rod was destroyed (ballpoint thread bashed up and bush ripped out).

There are 2 x types of transverse arms and you will probably find that you have fitted the wrong one.

The difference being is that the recess for the ball joint nut has more of a recess and you require a different seating cone.

Usually the eBay transverse arms are not compatible with the OEM seating cones.

Share this post


Link to post
Share on other sites
15 minutes ago, ZMANALEX said:

There are 2 x types of transverse arms and you will probably find that you have fitted the wrong one.

The difference being is that the recess for the ball joint nut has more of a recess and you require a different seating cone.

Usually the eBay transverse arms are not compatible with the OEM seating cones.

Here's my old transverse link. Any measurements that can be taken with verniers or is it obvious from to the eye?IMG_0687.JPG.c2fdc0162ce1a5a86467b4a5cb275452.JPGIMG_0686.JPG.bf470cfd94e570cde25b19e2ff8a5bbe.JPG

Share this post


Link to post
Share on other sites

That is an image of an OEM genuine Nissan arm with the correct recess.

You will probably find that the eBay arm that you fitted will have a deeper recess which will be obvious.

You will have the same fitment issues on both sides.

 

Share this post


Link to post
Share on other sites

Problem seems to have gotten worse, but I did a bit more investigation...

 

Jacked the car up so the FR wheel was just off the floor and put a pry bar underneath the tyre to apply upwards force. Felt the arms for movement, but everything seemed fine except a very slight movement in the upper arm ball joint.

However, rocking the pry bar left / right instead of up / down you can feel the knock much more in the upper arm ball joint. 
Edit: Can feel the same knock in the balljoint on the other side, so guess it rules that out.

 

Also noticed a knock when stationary, with the wheels on the floor, when rocking the steering wheel left / right, which is worse with the engine off. Getting underneath while someone is rocking the steering wheel there is a severe knock heard and felt in the tie rods / rack on both sides of the car, but I'm not sure if this is normal? Think it might be a red herring though as the knock is never heard when the left wheel hits bumps, only the right wheel or when tapping the brake lightly, unless it's the inner tie rod on the RHS?

Edited by OnlyAfro

Share this post


Link to post
Share on other sites

Make sure the top nut is fully tightened.......when i did my springs, i thought i had got the nut fully done up, but it wasn't and gave a random clunk at low speeds, almost exactly like you are describing...

Share this post


Link to post
Share on other sites
9 hours ago, Paul K said:

Make sure the top nut is fully tightened.......when i did my springs, i thought i had got the nut fully done up, but it wasn't and gave a random clunk at low speeds, almost exactly like you are describing...

On the strut? Not touched it, but I'll check when I get a chance.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

350z-uk.com

370z-uk.com

350z-uk.com

370z-uk.com

×
×
  • Create New...