rns

I have noticed during three days strange scary noise.

Noise appears when accelerating and at same time curving either left or right with slow or moderate speeds. No sound coming if not accelerating while curving.
And no sound coming even with heavy acceleration if steering is straight or only slight angle.

Noise sounds like metal grinding, metal scraping or sometimes slight knocking.
It feels quite clearly coming from the front of the vehicle.
Other possibly affecting thing is that weather got colder and has stayed below -25C/-13F since I remember hearing the noise first time.


What could cause the noise?


CV joints? Could both sides fail at the same time? I have had failed joints and they have just made clunking noise.

Wheels touching wheels arches? I saw no signs of scrapes there. No snow/ice remains seen either.

Engine mounts? Could failed mount allow motors+transmission packet to move and make noise? The car to my mind (although only Rx400 I have driven) suffers shaky ICE turn ons. Are mounts type that ambient temperature could affect them?

Wheel bearings? Wouldn't tight curving alone cause them stress enough to make the noise?

Transmission failing? Does Rx400 have limited slip in the front? Cvt oils have been changed regularly. Shouldn't this cause other signs too?


I just while ago finished about 150km/93miles drive that had no effect on the noise. Currently it's -30C/-22F outside.

Lazyj321

My first thought when you described the sound was cv joints. But metal grinding? Could your brakes be scraping the rotors with the metal wear tabs? That makes a nasty noise.

rns

Thanks, good one too, have to check. But noise appears only when accelerating.
Have to jack the car up

rns

Finally I jacked car up and changed control arms + lower ball joints front.
Same time I replaced right motor mount. Car was in warm garage.
I found no loose in Cv joints when hand twisting. Brakes are clean.

That slight scraping/clunking sound is still present.
Moment fits to CV joints but too harsh noise,
have anyone had such noise when CVs are broken?


Has anyone had worn half shafts from the end that goes in differential?
Because I think the sound could fit something like that grinding.
Those grooves in the end, if they wore out and ruin the diff outputs, that will cost something.

Lazyj321

Any updates on the noise?

Re: lower control arms, how did you get the bolt out from under the motor mount?

rns

Re: lower control arms, how did you get the bolt out from under the motor mount?[/QUOTE]

Noise is still there so I think it is just CV joints. They do face massive torque of electric motor so no wonder (soon hitting 200000km/125000miles)
I ordered both new half-shafts but until I have time for them, needs to take turns carefully.

Removing the motor mounts Quite a job, there is thread about it:
https://www.clublexus.com/forums/rx-...rms-a-arm.html
I feared to brake something while jacking engine/transmission up but all went well. Hardest job after all was to get the lower rear engine mount bolt back.

LSBen

It's your wheel bearings. My fronts makes a slight whirling sound when acceleration at slower speeds then sounds goes away when going faster. It's a good idea to replace them in pairs.

rns

I have ready both half shafts (Surtrack TO8222/TO8218) and bearings (Dura 29510063) but now sound is gone Weather do warmed to zero Celsius/32F but what could it affect?
I am almost sure I ruled out snow/ice etc. I didn't however check rear wheels because sound was so clearly coming from front, this was passengers opinion too.
Have to be alert if the noise comes back!

brendanf

It could still be the CV joints. My old Suzuki Aerio used to make noise when turning in cold weather until I drove it for awhile. Once it warmed up from driving the noise went away.

I would also recommend checking the oil in your front differential. Perhaps it is low or no longer lubricating properly.

ShrinkDoc

I went from Continental DSW's to Michelin A/S 3+ tires last month. Road noise increased dramatically. I looked on-line and noted that the A/S 3+ tires are known to have noise issues, even CR has noted this in their reviews. The Continentals are known for their quiet ride: the Michelins for their loud ride.

lexusisgs

We have removed ABS sensor first just to eliminate any impact on it due to use hammer to free ball joint or tie road end This is picture of lower ball joint that must be removed

Next was removal of tie road end ,we had great issue with safety pin on castle nut It was rusted and we couldn't easy remove it.We end up cutting off pin and drilling try the hole to meke room for the new safety pin

lexusisgs

Next step we had remove 22mm strut bolts.

Next ,removed brake bracket.and secure with wire .

Rotor was removed and drive shaft was pushed in ,than we have removed spindle with wheel bearing.NOTE THIS LEXUS HAVE PRESSED IN BEARING WHICH you can SEPARATE FROM HUB ASSEMBLY

lexusisgs

We were so lucky that removal of the hub was easy , didn't use hummer at all ,not much damage from rust

One more shot of tie road end that was taking too much time to remove .

Next few steps you have to take sweet time to remove this ring for ABS sensor .

professorm

I’m having a rattling scraping sound in my driver front wheel at low speeds. Then I also have a clunking sound when I am braking to about 15mph, then another clunk when I accelerate. It’s light by distinct clunk.

I recently, I replaced on both sides: brakes, rotor, pads, control arms, CV axles, ball joints. I thought it might be my brake backing, I don’t think it’s touching.

any ideas?