Disturbing screaching from F/N/S when towing...

[CantbeRSd]

Hi there all,

 

Does anybody have any experience of towing (problems) with a Yeti I can mine for an answer?

My 66-plate 140 4x4 drives absolutely fine. I added a 700kg trailer and a 700kg horse to the back and towed it for a short distance and the most unholy screeching, metal-on-metal, sound came from the front nearside. Take the trailer off...nothing.

It's not the brakes - checked.

It's not the wheel bearings - checked.

It's not the CV joint - checked.

I used it in 'Off-road' mode and still nothing so I don't think it's the Haldex. 

Waddya reckon? I'm baffled.

 

Thanks in advance, 

 

David

Edited 10 July, 2023 by CantbeRSd

[Urrell]

6 hours ago, CantbeRSd said:

I used it in 'Off-road' mode and still nothing so I don't think it's the Haldex. 

The "Off Road" mode does nothing to the Haldex, and as it's at the rear and the noise is from the front nearside probably rules that out.
Have the engine/gearbox mounts been checked?
What weight was on the tow-bar?

[J.R.]

6 hours ago, CantbeRSd said:

I added a 700kg trailer and a 700kg horse to the back and towed it for a short distance and the most unholy screeching, metal-on-metal, sound came from the front nearside

 

I'm not surprised there was an unholy screeching, you are supposed to carry the horse in the trailer not attach it to the back of it!

 

If you are lucky you might just get away with new horseshoes on the front end.

[CantbeRSd]

7 hours ago, J.R. said:

 

I'm not surprised there was an unholy screeching, you are supposed to carry the horse in the trailer not attach it to the back of it!

 

If you are lucky you might just get away with new horseshoes on the front end.

😂

[CantbeRSd]

7 hours ago, Urrell said:

The "Off Road" mode does nothing to the Haldex, and as it's at the rear and the noise is from the front nearside probably rules that out.
Have the engine/gearbox mounts been checked?
What weight was on the tow-bar?

The weight was about 1500kg all in. It was definitely coming from the front nearside of the car even at walking pace.

Weird - and alarming.

[Urrell]

3 hours ago, CantbeRSd said:

The weight was about 1500kg all in. It was definitely coming from the front nearside of the car even at walking pace.

Weird - and alarming.

Yes but what was the weight on the tow ball?

[J.R.]

I know what it sounds like and what I think it is but have no suggestion as to why it is happening.

 

I believe and others may correct me here, that if the left front wheel has no traction lets say offroad you are cross axled and the wheel is off the ground, then there would be no drive to the rear wheels because that comes from the bevel drive from the right driveshaft which would be stationary while the left wheel was spinning freely.

 

To counteract this the ABS controller will brake (severely) the left front wheel thus allowing drive to the other 3 wheels.

 

My MK1 Octavia used the same system for traction control and it made a horrible graunching sound each time it cut in from when pulling across a junction smartly if the road conditions were greasy.

 

If you are pulling away against a severe braking force on the left front wheel front brake it would sound as you describe but I cannot see why it is happening, have you had any warning lights on for ABS, Traction Control, ESP, TPMS etc?

Edited 11 July, 2023 by J.R.

[J.R.]

Get someone to walk beside the vehicle watching the front brake disc and caliper to prove or disprove my hypothesis, if its not that they will be able to localise the sound better than you from the drivers seat.

[Urrell]

47 minutes ago, J.R. said:

If you are pulling away against a severe braking force on the left front wheel front brake it would sound as you describe but I cannot see why it is happening, have you had any warning lights on for ABS, Traction Control, ESP, TPMS etc?

That's why I asked what the weight was on the tow ball, if severely overloaded it would have that effect.

[Kenny R]

Perhaps a result of the tow ball weight and the Haldex not driving the rear wheels is the reason for the front wheel spinning.

Has the Haldex oil and filter maintenance been done as per schedule and should have been done at least twice by now.

[J.R.]

Nobody has said that the front wheel is spinning.

 

7 hours ago, Urrell said:

That's why I asked what the weight was on the tow ball, if severely overloaded it would have that effect.

 

Vehicle does not know how much nose weight is on the tow ball and mine at least does not know whether the springs are on the bump stops or at full extension.

[CantbeRSd]

9 hours ago, J.R. said:

Get someone to walk beside the vehicle watching the front brake disc and caliper to prove or disprove my hypothesis, if its not that they will be able to localise the sound better than you from the drivers seat.

I did just that, which I how I know how local it was 👍

[CantbeRSd]

9 hours ago, J.R. said:

I know what it sounds like and what I think it is but have no suggestion as to why it is happening.

 

I believe and others may correct me here, that if the left front wheel has no traction lets say offroad you are cross axled and the wheel is off the ground, then there would be no drive to the rear wheels because that comes from the bevel drive from the right driveshaft which would be stationary while the left wheel was spinning freely.

 

To counteract this the ABS controller will brake (severely) the left front wheel thus allowing drive to the other 3 wheels.

 

My MK1 Octavia used the same system for traction control and it made a horrible graunching sound each time it cut in from when pulling across a junction smartly if the road conditions were greasy.

 

If you are pulling away against a severe braking force on the left front wheel front brake it would sound as you describe but I cannot see why it is happening, have you had any warning lights on for ABS, Traction Control, ESP, TPMS etc?

There was no problem with traction as this was on tarmac. There were no warning lights, either. Bloody mystery.

At least it’s under warranty. Mega phew.

6 hours ago, Kenny R said:

Perhaps a result of the tow ball weight and the Haldex not driving the rear wheels is the reason for the front wheel spinning.

Has the Haldex oil and filter maintenance been done as per schedule and should have been done at least twice by now.

 Cheers, yeah, all done via Skoda garage to schedule.

[idleness]

30 minutes ago, CantbeRSd said:

Cheers, yeah, all done via Skoda garage to schedule.

I will put money on the fact that Skoda didn't change the filter if a mk4 or clean the screen if mk5.

If you only change the oil and not the filter then the haldex can die before the next service interval.

Happened to me 

[Urrell]

1 hour ago, J.R. said:

Nobody has said that the front wheel is spinning.

 

 

Vehicle does not know how much nose weight is on the tow ball and mine at least does not know whether the springs are on the bump stops or at full extension.

You did suggest it with the brake on the spinning wheel to get traction, with too much weight on the tow-ball it could taking weight off the front causing that!

Edited 11 July, 2023 by Urrell

[J.R.]

No I did not suggest that the wheel was off the ground or spinning, I theorised that for some reason possibly a malfunction of a wheel speed sensor that the system might be activated.

 

The OP said that he was walking beside the car, the wheel would not have been off the ground and the car not accelerating to spin the wheel.

 

Editted, I can see now that I did not put my thoughts over coherently, I was in a rush before going out, I neglected to write that for some reason the system is acting as if it had lost traction but I did say later "but I cannot see why it is happening"

Edited 11 July, 2023 by J.R.

[J.R.]

Another question for the OP.

 

Does the car have the all singing & dancing "coded" towbar electrics?

 

If so then maybe the fact that it is detecting a trailer attached (by the insertion of the lighting socket) is for some reason triggering this anomaly, almost certainly in conjunction with something else misbehaving.

 

I suggest that you try towing a similar weight but for the test do not connect the lighting plug, if the problem does not manifest then we will be one step closer to nailing it down.

[CantbeRSd]

13 hours ago, J.R. said:

Another question for the OP.

 

Does the car have the all singing & dancing "coded" towbar electrics?

 

If so then maybe the fact that it is detecting a trailer attached (by the insertion of the lighting socket) is for some reason triggering this anomaly, almost certainly in conjunction with something else misbehaving.

 

I suggest that you try towing a similar weight but for the test do not connect the lighting plug, if the problem does not manifest then we will be one step closer to nailing it down.

Yes - good thinking 👍

[CantbeRSd]

On 11/07/2023 at 09:43, J.R. said:

I know what it sounds like and what I think it is but have no suggestion as to why it is happening.

 

I believe and others may correct me here, that if the left front wheel has no traction lets say offroad you are cross axled and the wheel is off the ground, then there would be no drive to the rear wheels because that comes from the bevel drive from the right driveshaft which would be stationary while the left wheel was spinning freely.

 

To counteract this the ABS controller will brake (severely) the left front wheel thus allowing drive to the other 3 wheels.

 

My MK1 Octavia used the same system for traction control and it made a horrible graunching sound each time it cut in from when pulling across a junction smartly if the road conditions were greasy.

 

If you are pulling away against a severe braking force on the left front wheel front brake it would sound as you describe but I cannot see why it is happening, have you had any warning lights on for ABS, Traction Control, ESP, TPMS etc?

Hiya - good thinking, but no dash lights and the sound was constant when on the move. Just weird!