General Front Suspension Clunk Noise

[umanemo]

2000 FIAT Ducato 18Q - 2.8 TD, Motorhome.

Back again with this clunk in the front suspension.

I was told by the first mechanic that it was the King pins and they replaced them, then it returned. I was then suspicious that it was the rear engine mount which was quite torn up, so I replaced that. No luck the noise appeared again.

The noise has been around irregularly for some 5,000Km's. It mostly occurs only when starting to move from a complete stop, more likely to occur when pulling to any uphill angle and possibly only after aggressively braking prior to moving once again, I.E. a stop light or roundabout, it's not regular but occurs randomly, it's a single thump or clunk somewhere generally in the RH side below the passenger seat (it's a LHD). I can "feel" it at the accelerator petal just slightly but the noise itself is just a bit more obvious to the passenger, but it is slight and not a loud noise. It went away for a few weeks (ca. 1-2000Km's), it does go away at times, but it reappeared once or twice lately and I just want to get it sorted. Hoping that someone with this age of Ducato has been here before with this issue and can pinpoint it for me.

BTW, the last time I posted this issue someone suggested to circle the vehicle LH and RH to listen for the noise, but it didn't produce any results.

Any explanation is welcome. I will take it in again to a mechanic tomorrow and it would be nice to eliminate a great deal of searching for the cause if possible and help point out the possible causes to him.

Thanks!

 

[Torq]

My 01 ducato used to knock when I took my foot off or put it on the accelerator, it was the cv joint, threw in a second hand driveshaft and the noise was gone.

 

[g8rpi]

2000 FIAT Ducato 18Q - 2.8 TD, Motorhome.

Back again with this clunk in the front suspension.

I was told by the first mechanic that it was the King pins and they replaced them, then it returned. I was then suspicious that it was the rear engine mount which was quite torn up, so I replaced that. No luck the noise appeared again.

The noise has been around irregularly for some 5,000Km's. It mostly occurs only when starting to move from a complete stop, more likely to occur when pulling to any uphill angle and possibly only after aggressively braking prior to moving once again, I.E. a stop light or roundabout, it's not regular but occurs randomly, it's a single thump or clunk somewhere generally in the RH side below the passenger seat (it's a LHD). I can "feel" it at the accelerator petal just slightly but the noise itself is just a bit more obvious to the passenger, but it is slight and not a loud noise. It went away for a few weeks (ca. 1-2000Km's), it does go away at times, but it reappeared once or twice lately and I just want to get it sorted. Hoping that someone with this age of Ducato has been here before with this issue and can pinpoint it for me.

BTW, the last time I posted this issue someone suggested to circle the vehicle LH and RH to listen for the noise, but it didn't produce any results.

Any explanation is welcome. I will take it in again to a mechanic tomorrow and it would be nice to eliminate a great deal of searching for the cause if possible and help point out the possible causes to him.

Thanks!

A single clunk like you describe could be a suspension mounting moving. I'd be looking for loose or broken fixings such as subframe, rollbar or strut mounting bolts and brackets. It's not unknown for these to be loose or missing after work like clutch replacement.

Robert G8RPI

 

[umanemo]

Thanks Torq,

I had the Rubber CV boots replaced with the King pins job. Do you think they would have noticed play in the CV's at that time or would it not have been obvious? As they were in there to find a suspicious clunking you would think they would have gone straight to the CV's first, but you never know what they're thinking.

 

[umanemo]

g8rpi - Good point. I did have the clutch replaced about 6K ago. Don't remember when exactly the clunk started but definitely after the clutch was replaced.

 

[corcai]

Rear gearbox mount or inner tripod joint as torq has pointed out.

 

[EJB]

I've had a similar 'loud clunk' from the RH, drivers, side of my Ducato based Motorhome.
Had it for a few years (Only 5,000ish miles a year).
It only happens perhaps once every few days on moving off as the clutch is engaged.
Not necessarily on the first start of the day.
My local service garage always checks everything on it's yearly service/MOT and has never found the cause.

Had both half shafts replaced due to one being 'bent/twisted' in a heavy start on a gravelly and very steep mountain road. The vehicle did run reasonably as long as the throttle wasn't depressed too much on acceleration.
The 'clunk' still persists....occasionally.

So the half shafts were not the culprit!

PS. Changed the wrong half shaft first as my wife later indicated 'I did tell you it was the other side!

 

[umanemo]

I've had a similar 'loud clunk' from the RH, drivers, side of my Ducato based Motorhome.
Had it for a few years (Only 5,000ish miles a year).
It only happens perhaps once every few days on moving off as the clutch is engaged.
Not necessarily on the first start of the day.
My local service garage always checks everything on it's yearly service/MOT and has never found the cause.

Had both half shafts replaced due to one being 'bent/twisted' in a heavy start on a gravelly and very steep mountain road. The vehicle did run reasonably as long as the throttle wasn't depressed too much on acceleration.
The 'clunk' still persists....occasionally.

So the half shafts were not the culprit!

PS. Changed the wrong half shaft first as my wife later indicated 'I did tell you it was the other side!

At least I know I am not alone! Thank's

 

[corcai]

You're definitely not alone, the rear gearbox mount is a common issue, I've had spurious aftermarket ones fail at 5k. The left inner tripod also wears at an accelerated rate due to the extreme angle it drives at you can usually check it by feel rather then removing it and replacing it unnecessarily. You need two jacks and a jack stand for safety.

-Measure the distance between the top of the tyre and the arch
-Put the van in gear
-Jack the left side of the van at the front jacking point and insert jack stand.
-Jack the wishbone until the distance between the tyre and the arch is the same as measured- this returns the driveshaft to normal operating angle.
- Catch the outside of the tyre and rock the wheel back and forth to check for wear.

 

[umanemo]

You're definitely not alone, the rear gearbox mount is a common issue, I've had spurious aftermarket ones fail at 5k. The left inner tripod also wears at an accelerated rate due to the extreme angle it drives at you can usually check it by feel rather then removing it and replacing it unnecessarily. You need two jacks and a jack stand for safety.

-Measure the distance between the top of the tyre and the arch
-Put the van in gear
-Jack the left side of the van at the front jacking point and insert jack stand.
-Jack the wishbone until the distance between the tyre and the arch is the same as measured- this returns the driveshaft to normal operating angle.
- Catch the outside of the tyre and rock the wheel back and forth to check for wear.

I'll try it. Will report back as soon as we get a chance to stop and effect your recommendation. Thanks!

 

[rolandbrindley]

It's news to me that a Ducato has king pins - mine hasn't, they have McPherson struts instead so there is no king pin at all just a glorified shock absorber.

Most front end noise comes from the CV joints, although a track control arm rubber that's rotted and dropped out will lead to metal to metal contact, and a clunking noise as the power comes on and off.

 

[witzend]

Mine did the same it was movement of disc pad in holder

 

[umanemo]

Still have the issue. Can't pin it down but will keep trying. Thanks!

 

[rolopolo]

Front shock absorber top bearings and mounts?

 

[umanemo]

I had that idea at the start but got so involved in other possibilities that I had forgot to check this. I just was so sure it was under the passenger seat LHD. Thanks for jogging my memory, I'll have the passenger keep a hand on the strut column once in a while to feel for the clunking.

 

[rolopolo]

I used to sell loads of these on Peugeot boxers of a similar age to your fiat (same setup I think) and I’ve had them done twice on ducato’s over last 9 years, knocks mainly when turning slowly, but knocks over bumps etc

 

[Yammie 56]

You're definitely not alone, the rear gearbox mount is a common issue, I've had spurious aftermarket ones fail at 5k. The left inner tripod also wears at an accelerated rate due to the extreme angle it drives at you can usually check it by feel rather then removing it and replacing it unnecessarily. You need two jacks and a jack stand for safety.

-Measure the distance between the top of the tyre and the arch
-Put the van in gear
-Jack the left side of the van at the front jacking point and insert jack stand.
-Jack the wishbone until the distance between the tyre and the arch is the same as measured- this returns the driveshaft to normal operating angle.
- Catch the outside of the tyre and rock the wheel back and forth to check for wear.

How much movement is normal?