Technical Ducato 2003. 2.8 jtd. Source of squeaking in front suspension?

[wanderer 888]

Hello everyone, this Fiat is a motorhome and I have had this front suspension squeak for over a year now. It is particularly noticeable when I go over bumps at low speed. During this time I have the front shock absorbers replaced, plus the top parts and the bearings that go underneath them.

I have had three different mechanics look for this squeak. I got them to take off the cover plate under the engine and they have poked and prodded with a crowbar the various bushes in the front suspension - not found anything. All parts appear to be intact and working properly.

Recently when this was done and they put the plate back on, the squeak was even louder. Would anyone know what this indicates? Thanks for your time!

 

[Anthony489]

Hi wanderer

It might be the two main rubber bushes which surround the anti-roll bar (sway bar). If you go over a hump in the road where both front wheels go up and down together, the bar twists in these. This sort of motion is difficult to replicate in the workshop with a pry bar. A good squirt of aerosol rubber and nylon lubricant may temporarily silence it.

Sometimes a squeak will go away in wet weather, if the guilty part is exposed to road spray. The water acts as a natural lubricant. Maybe Portugal isn't wet enough !

 

[wanderer 888]

thanks so much for the suggestion, sounds like a very feasible reason!

 

[IceVovo]

The 2.8 JTD has heavy duty Macpherson struts.
There is the bearing on top and a bearing plate.
The mounts.
A heavy duty coil spring with a matching rubber pad.
The shock inside the coil spring.

Maybe your shock is worn but not completely gone?
Any oil leaks?
The shocks do wear out over time.

Visible signs are oil/grit accumulation on the spring etc.

Squeeks. Tricky to source.
You have narrowed this down to a wheel?

Drive one wheel up an incline or gutter.
Do each side.
Have someone listen outside vehicle.
Might help narrow down which side?

Keep us posted...

 

[wanderer 888]

The 2.8 JTD has heavy duty Macpherson struts.
There is the bearing on top and a bearing plate.
The mounts.
A heavy duty coil spring with a matching rubber pad.
The shock inside the coil spring.

Maybe your shock is worn but not completely gone?
Any oil leaks?
The shocks do wear out over time.

Visible signs are oil/grit accumulation on the spring etc.

Squeeks. Tricky to source.
You have narrowed this down to a wheel?

Drive one wheel up an incline or gutter.
Do each side.
Have someone listen outside vehicle.
Might help narrow down which side?

Keep us posted...

Sorry, I did not see your post from a few weeks ago, thanks for the suggestion! Very hard to diagnose and is the most noisy when the van is cold, going over rough stony ground at low speed. Pretty much the only time it does it, unless I hit a speed bump too fast, so the suspension seems to be working, I have done about 40,000 km's since this started. It is still squeaking and the latest in this long running saga is this:

1. New Sachs shockers and their top mounts - 8 months ago.
2. New stabiliser bar rubbers - 2 months ago.
3. New lower ball joints - few days ago.
4. New central engine mount rubber - a few days ago.

The mechanic who is looking at it now, suspects that the top part of the shock absorber is not seated in the top mount properly. But to do that is a 3-4 hour job taking out the dashboard etc. - which has already been done when the new shocks/mounts were installed. Even if that job was not done properly, the squeaking noise has been there for about 8 months previous to them being fitted!

So other parts that might be the problem....

- Front suspension control arms (without about 3 rubber bushes in each)
- Tie rod ends
- Coil springs - would they create a squeaking sound?

Thanks for your ongoing attention everyone!
-

 

[StHawk]

Have you figured out if it’s a metal to metal squeak or a metal to rubber squeak? Squeaks in suspension are really hard to diagnose, I would find some silicone spray and spray the anti roll bar bushing to start with. In my experience they are most often the culprit as they are only under tension part of the time so are allowed to distort.