260Z banging noise under armrest area

[Racer X]

8 hours ago, Shawninvancouver said:

 

my pal insists it’s the u joints that hold the tie rod to the rear diff.  Is that even possible ??

U joints connect rotating shafts, such as a driveshaft, halfshaft, steering shaft.

Tie rods connect the steering rack to the steering knuckle.

 

So, no, not even in the same ballpark.

 

[Racer X]

7 hours ago, Shawninvancouver said:

Or as in the drive shaft was spinning and the car wasn’t moving.  Reverse was fine abs the car shifted fine once going. 

Now think about this for a moment.

If the driveshaft was spinning, and the car wasn't moving, then later, in reverse, it moved fine, you just stepped into The Twilight Zone.

You really won't know what is causing the noise until you get under the car and have a look.

 

 

[Shawninvancouver]

Here are photos from underneath.   Strap is ok. Diff mount is ok. Looked like shaft connector on back was ok.  Can you send anything weird in photos ???

[Racer X]

26 minutes ago, Shawninvancouver said:

Here are photos from underneath.   Strap is ok. Diff mount is ok. Looked like shaft connector on back was ok.  Can you send anything weird in photos ???

Not a single picture of the nose mount on the diff showing the condition of the rubber.

I would take a look there, use a pry bar and see if there is any play. Those mounts tear somtimes, and that might be the clunking you are hearing.

Also check the u joints on the driveshaft and half shafts.

 

 

 

[Zed Head]

The diff mount seems to be sitting high.  Look up in this hole and see if there is a nut on the threaded stud.

Stole from Namerow.

[Shawninvancouver]

ok - i will look there for a nut..  what would the effect be with no nut there?? bouncing up and down??  isnt the diff just sitting on that rubber??

so even with no nut it just rests on it??

i looked at u joints as good as i could and they looked ok...

i guess strap and mount look ok.. 

[Racer X]

Here is a video of how to check universal joints, and what you will see when one is bad (this one is really bad, any play is unacceptable). Your Z has 6 universal joints.

Check them all.

 

 

The front differential mount is two pieces of metal joined with rubber. One of the metal pieces is bolted to the differential, the other to the cross member. If both parts are bolted securely, then it is possible that the rubber has torn away from the metal. To check for this use a prybar too lift the nose of the differential, and observe if this is the case.

The transmission mount, and the engine mounts are of similar design, and are checked the same way.

Check them.

 

Also, check the exhaust. Grab the muffler outlet and see if it wiggles, observe how much, and if you hear any part of the exhaust hitting anything. A little wiggle is OK, a lot, not so much. Examine all of the mounts, repair or replace any broken parts. Bailing wire or coathangers are not acceptable repair materials. 

 

[Shawninvancouver]

ok.. i will check those..  it sounds like it could be the rear U joint....  if it is..  will this one work as a replacement????

https://www.danaaftermarket.com/spicer-automotive/automotive-driveshaft/universal-joints/part/universal-joint/5-1501X?cat1=0&str=5-155X&cp=0&catalog=PIMS_NA&partType=PART

is this the part i need??

 

[Racer X]

7 hours ago, Shawninvancouver said:

ok.. i will check those..  it sounds like it could be the rear U joint.... 

Did you find any play in it?

 

7 hours ago, Shawninvancouver said:

 

if it is..  will this one work as a replacement????

https://www.danaaftermarket.com/spicer-automotive/automotive-driveshaft/universal-joints/part/universal-joint/5-1501X?cat1=0&str=5-155X&cp=0&catalog=PIMS_NA&partType=PART

is this the part i need??

 

Is it listed as the replacement?

Are the dimensions correct?

[Shawninvancouver]

yes - listed as a replacement - not sure if i get one before taking to the shop or let him put it on the hoist and see what it needs...

[Zed Head]

You can buy them at any auto parts store.  No need to wait for delivery, just get them when you need them.

[Shawninvancouver]

my auto store needs to order in from warehouse...  lordco

also.. how could the muffler have been causing a knocking noise?