Parts Wanted: 280z Stub Axle and Companion Flange

[Terrapin Z]

PM sent.

 

[Racer X]

14 hours ago, ckurtz2 said:

@Racer X I think the vibrations are so bad that it is affecting the front wheels, but I don't think it is truly stemming from the front. Anyways while its on stands for peace of mind I am going to retorque the front axles and make sure it isn't too loose or too tight. Quick and easy thing to do. How exactly do I check runout with the dial indicator, and where do I get one? 

     @Zed Head

If the vibration is coming from the rear and it is shaking so bad that it makes the front wheels shake, you have bigger problems than excessive runout at a rear hub.

There is no such thing as too loose or too tight. Fasteners are either tight, at the correct torque, or they aren't.

 

Checking runout of any rotating part is a simple process. 

Get a magnetic base dial indicator:

 

 

Or:

 

 

 

 

Although I would buy a high quality one from Starrett, or Sumitomo, cheap units are available on the web for around $20 to $30.

[ckurtz2]

Got under the ole car pulled on all sorts off stuff and everything was tight. Re torqued the front wheel bearings very precisely as per the manual (21.5ft/lbs) and then backed off 60 degrees. @Racer X that's what I mean by too loose or too tight. If you don't back off the nut after you torque it then it's too tight.

Once I finished the job I put the wheels on and gave some pretty hard tugs. Noticed a little slop. Spent about 10 minutes finding the source of the slop, and it turns out the gland nut to the passenger front strut was super loose. Tightened it up and went for a test drive and sure enough the front steering wheel shaking is gone. Still fighting a vibration, but it is much smaller and most definitely from the rear. Pulling the driveshaft and making sure it's balanced good. Then I will go down the route of checking runout:) One step at a time.

[ckurtz2]

Checked the driveshaft. Found that the rear ujoint had slop, let me know if this ujoint is bad. Seems bad to me. Annoying considering it's brand new, but I will take it back to the shop today.

Here is the video. Let me know your thoughts if you think this can cause a vibration. It can move back and forth about 1/4 of an inch. The caps themselves are locked in place, but the joint can move up and down.

 

Edited September 12, 2022 by ckurtz2

[Zed Head]

14 minutes ago, ckurtz2 said:

Seems bad to me.

Bad?  It's terrible.

You really should put your car details in a signature.  It's PITA to search around to confirm what people are talking about.

Your 280Z should not have replaceable u-joints.  Those clips holding the caps in should not be there, they're not even Nissan style.  That is an aftermarket shaft or somebody has modified the staked shaft that came with the car.  Might be why the u-joint failed and it might still have a vibration after you install new joints.  I'd get a new shaft or a used 280Z shaft.  Watch out for 1975 shafts, they're different.

[Mark Maras]

 Any detectable movement in a u-joint is bad and will be felt.

[ckurtz2]

@Zed Head I will fix the signature. Anyways, yes I brought my original rusty driveshaft to a shop to be restored and they said the joints were unreplaceable. So they built me a new shaft and called it good. Brought the shaft back today and they covered it under warranty and fixed it/ rebalanced the driveshaft. Turns out it was a defective u-joint. I'll reinstall it and see how the car rides. I am going to guess this is going to fix most of my issue:)

[Zed Head]

58 minutes ago, ckurtz2 said:

Turns out it was a defective u-joint.

Hope so.  Seems unlikely though, doesn't it?  Hopefully they fixed the root cause.

Should make a huge difference.  That was a lot of slop.  The bonus is that you found those other problems while looking for that one.

[ckurtz2]

7 minutes ago, Zed Head said:

Hope so.  Seems unlikely though, doesn't it?  Hopefully they fixed the root cause.

I think the "defective ujoint" was them making an excuse for an improper installation the first time around. I'd be willing to put money on it💩.

Anyways, yes finding the loose gland nut was a huge plus. Now I am going to tighten them up on every shock even if they seemed tight while tugging on them.

 

[ckurtz2]

And to put this topic to rest. Car rides like a soft cloud now. Teleported the Z to Mexico and did some 100+ runs. Didn't feel any shake in the steering wheel or rear end all the way through the gears. I guess you just can't trust new or remanned parts these days. Glad the solution was this though and not the stub axle. I know the stub axle still has its problems and likely will need to be addressed in the future, but as the old adage says "if it aint broke don't fix it". 

Thank you everyone for your advice and help😄

[Mark Maras]

19 hours ago, ckurtz2 said:

@Zed Head I will fix the signature. Anyways, yes I brought my original rusty driveshaft to a shop to be restored and they said the joints were unreplaceable. So they built me a new shaft and called it good. Brought the shaft back today and they covered it under warranty and fixed it/ rebalanced the driveshaft. Turns out it was a defective u-joint. I'll reinstall it and see how the car rides. I am going to guess this is going to fix most of my issue:)

I'm glad the issue is fixed but I'm stuck with the question, why didn't the bad u-joint show up when they balanced it previously?

[ckurtz2]

@Mark Maras fantastic question I can't answer.