What has failed on the PITA V70R this time?? - Update 17th Sept 2024 Topic is solved

[scot850]

I have almost 100% stopped driving this car as I am plain fed up constantly repairing it. So the 'boss' is now using it as her summer car.

She started early after it was back on the road this year saying there is a rubbing or knocking noise 'somewhere' under the car. It is random and comes and goes. Our son has driven the car 2-3 times and says he has heard nothing.

Today my wife picked me up at the repair shop where my Toyota is in for checks. On the way back I drove it and couldn't hear anything initially. Then I thought I heard something but could not isolate where it was coming from. It is random and got a little worse on our way back but it certainly sounds like it is a rotating part of the driveline.

It seems to be worse when turning right, but not always, and can do it after straightening up. It sounds like a bearing but it sometimes sounds like it comes from the front and other times from the rear, then the middle. Only thing I can think of is the prop-shaft. If not that then maybe the VC unit or the angle gear.

I checked the car up on the hoist about a week ago and couldn't find anything loose in the driveline or noisy. Prop-shaft and center bearing seemed good too.

I will pull the prop-shaft and see if that changes anything. The only issue with that is that if it is anything attached to it like the VC or angle gear, and the noise goes away, it could still be something else.

I guess I have to start somewhere.

Neil.

[850 LPT]

Sorry to hear this Neil, but I think you are on the right track in terms of troubleshooting.
Removing the prop shaft is a good and logical first step.

Good luck, Dirk

[scot850]

That is now on my agenda this afternoon, between figuring out if we want to take on resurrecting the 02 XC70 for a student friend of ours (we have decided on engine diagnostics before spending any more money on it), removing the V70R prop-shaft this afternoon, and doing a thermostat and coolant swap on another students V50 T5 AWD this evening!

Neil.

[xanthefin]

Your radio is turned too low. You start hearing sounds you dont like.

[scot850]

Well it turned out to be the small heatshield by the front of the cat mounted to the bottom of the downpipe to protect the front coupling of the prop-shaft from the heat of the downpipe and cat Both mounts had broken through and allowed the shield to move on RH turns or over bumps enough to rub on the angle gear to prop-shaft flange. Spent probably close to 3 hours fighting the inaccessible 2 mounting bolts which fortunately came out with PB Blaster, and then refitting the (naturally) NLA heatshield back on with a washer either side and dropping them multiple times. Eventually used a large zip-tie to hold it in place while fitting the bolts.

Then I just had to refit and torque the prop-shaft bolts I had removed.

Today I'll find out if that was the answer or only part of it.

Neil.

[scot850]

WRONG! - Naturally it couldn't be that easy (it wasn't). The boss said it seemed better but there is still a noise. This car is a real PAIN!

It will go back up on the hoist again tomorrow to check the heatshield is still attached, and if it is, the prop-shaft will come off this time. Maybe a trial run first to see if the noise location is more consistent. Problem was the noise seems to move. If there is nothing obvious again, then off with the prop-shaft followed by another test drive. Did I ever say how much I hate this car??

Neil.

[scot850]

Took the car out before removing the prop-shaft. Typical. That stupid heatshield rattling/rubbing was masking noise from somewhere else.

So, Drive straight, no noise at all, no shaking. Turn left, no noise no vibration/grumbling/knocking. Turn right, knocking/grumbling 100% of the time. Normally, I would consider this an almost 100% diagnosis of a LH front wheel bearing. However, I'm not convinced the noise is coming from the LHF corner. I checked the wheel bearing for movement and it is 100% solid, no movement. The RHF bearing does have some movement. Both front axles have solid boots and no noticeable play.

I have a pair of 00 year front axles with the RH support bearing solid. I also have a brand new used and aftermarket support/carrier bearing.

So, do I spring for the front wheel bearings? I would replace both anyway if I have to replace one. That way, if I pull the front wheel bearings it is easy to remove and check the axles off the car to be sure they are right.

BUT!! - Is this a clear cut diagnoses? Could something else be bad? :

1) Angle gear/collar to auto trans - Surely if it was bad it would be bad in both directions and in the straight ahead??
2) Prop-shaft. No obvious movement at all in the front, middle support or rear bearings. The only thing I would wonder about is the support bearing rubber, but it looks OK. Again, if this would be bad, why is it only bad in one direction?
3) VC unit - Front bearing or vc unit itself. Again, why only bad in one direction. Possibly the rubber mount on the VC as it is mounted only on the RHS. But again, why would it cause a know on one side only on turning?
4) Noise seems to be from the front of the car, forward of the driver, so currently thinking the rear axle and bearings are ok.

So currently holding off on the prop-shaft removal as I don't think it or the rear driveline is the issue.

Thoughts and inputs appreciated!

Neil.

[abscate]

Ive never felt play in any of my growlers and one of Grunhildes bearings was quiet, but was so locked up it couldnt be turned by hand.

Upshot - when they growl on turning, replace them.

I propose a new name for Sonic Blue

PITA-R the Great

[scot850]

Perhaps, 'Not so grate'.................!

Neil.

[abscate]

Inspect engine mounts too.

RHS standard P80s mount

The LHS has a special AWD Buddist temple mount that can go south on you,