Technical Help with diagnosing groaning and thumping sound

[Gian Deau]

Recently, my 2016 500X Lounge (~75K miles) has begun making a groaning sound from the front left, when turning, and a thumping sound from the front, when going over bumps.

I thought maybe it needed power steering fluid, but (after I bought some), I discovered the car doesn't take power steering fluid.

I would really appreciate it if someone could help me narrow down the likely problem.

Thank you!

 

[s130]

Difficult to diagnose remotely.

Drive the front right wheel onto a piece of thick cardboard. Jack from left wheel clear of ground. With steering straight check for bearing play or noise when wheel is rotated. Put on full left lock and check again especially for any noise / roughness when wheel is rotated. Repeat of full right lock.

Repeat for right wheel.

When doing the wheels before lowering each wheel place a spade (reversed) under the wheel and lever / jiggle the wheel up and down in the three positions (left lock, center, right lock). Any noises etc. Any play in the bottom swivel joint?

Bit tedious but a starting point.

 

[porta]

The groaning sound is usually a sign the wheel bearing has gone but, coupled with the knocking, is more likely to be the CV joint…other knocking could be, as s130 checks for bearings etc above, any of the suspension bushes/track rod ends/drop links etc…

 

[Ralf S.]

I'd say it's more likely to be suspension rather than wheel bearings, CVs and driveshafts.. I tend to get through wishbone arm bushes and drop links twice as often as wheel/drive hardware.

A groan when the car is turning could be the bushes complaining, since the suspension is being "twisted"... so it's a wheel off job and visual inspection of the lower arm bushes and drop links/tie rods for me. If you spray the bushes with some lithium grease/WD40 or the like; if that makes the noise recedes then at least you know that's the cause.

Groaning alone does not make the job "urgent" but have a look at the inner tyre shoulders. If you have increased wear then that will also suggest the wishbone arm bushes are tired. If the tyres are fairly worn out, then just make sure they don't wear through to the canvas... but then don't change the tyres without replacing the arms. Arms first.. then tyres, and when you replace the tyres, get the alignment checked/re-done.


Ralf S.