Yeti 170 is braking rear right wheel randomly

[NorwegianYeti]

Hi, my car has began to act extremely weird and dangerously, when driving along in higher speeds, say above 50kph and releasing the throttle it suddenly brake the right rear wheel, however I do not think its the brakes, there´s a horrible sound, especially when going slow. When it began it didn't happen every time, although it has quickly gotten worse at parking  speeds I have to apply throttle (its undriveble), if i release the throttle its not far off locking up the wheel on gravel, however when up to speed it works better. When I got home from a quick trip just now (2nd day since I started to notice this and it quickly got super bad). 

 

Smoke started coming out of the engine bay (temp was good). I would think brake/parking brake if it would´t be for the nasty sound (maybe caliper?) or wheel bearing that has catastrophically welded it self? But considering the smoke and where it came from I´d say driveshaft bearing, but that would have impacted both wheels accordingly right? The sound is metallic and inconsistent like it catches on to something and gets released), the smoke smells like burnt oil, really bad so probably hydraulic? Burnt brake pads does not smell that good either thought but the all the discs are cold. 

 

 

 

[J.R.]

Failure of either the bevel drive gearbox to the propellor shaft, its at the front and a common failure point.

 

Or failure of the rear differential.

 

Regarding the first had you noticed any oil drips or stains on the floor or the front undertray in recent weeks? If so that was the oil seal failing on the bevel drive box and once dry it started breaking up.

 

Regarding the second have you had the Haldex oil changed in recent weeks? If so then they probably drained all the oil out of the diff by mistake.

[J.R.]

Its good that you felt the temperature of the discs, I think we can now rule out uncommanded brake actuation which probably would have an ABS block failure.

[NorwegianYeti]

3 minutes ago, J.R. said:

Failure of either the bevel drive gearbox to the propellor shaft, its at the front and a common failure point.

 

Or failure of the rear differential.

 

Regarding the first had you noticed any oil drips or stains on the floor or the front undertray in recent weeks? If so that was the oil seal failing on the bevel drive box and once dry it started breaking up.

 

Regarding the second have you had the Haldex oil changed in recent weeks? If so then they probably drained all the oil out of the diff by mistake.

 

1, no drops

2, Yes..

 

Just bought the car and thankfully they left 3 months of warranty, just had a shop replace the return diesel pipe last week, and they were super good about it. But regarding 2, I think the Haldex oil was changed in march as Multi-disc clutch oil 1L is stated on the latest service receipt.

 

Would the bevel drive gearbox just impact one of the rear wheels?

[J.R.]

They drained the wrong drain plug leaving the differential dry and then struggled to get the 1l of Haldex oil in the Haldex part of the diff (the front) because the old oil was still in there, easy to do and I made the same mistake despite being aware of the possibility and having another forum member on hand as a second opinion.

 

I was partially sighted and working on my back in the gloom and unfocussed, a mechanic with a ramp and workshop lighting does not have the same excuses but many many have made the mistake.

 

Thankfully they should cover it under warranty, if you have any suspicion that they might try to wriggle out take it somewhere else first and get them to confirm that the diff has failed and is dry of lubricant.

 

It does not explain the smell from the front but that could have been a DPF regeneration in progress.

[J.R.]

9 minutes ago, NorwegianYeti said:

Would the bevel drive gearbox just impact one of the rear wheels?

 

No but if the Haldex is engaged and the bevel drive box seized, th prop not wanting to turn but the rear wheels turning what would happen is one rear wheel would try to turn backwards while the other is dragged forwards.

 

From what you have said though I'm convinced the diff is destroyed through having been run dry, have you heard increasing transmission noises recently?

 

Many many people have suffered the same after having a Haldex service done by a garage or main dealer.

[NorwegianYeti]

13 minutes ago, J.R. said:

They drained the wrong drain plug leaving the differential dry and then struggled to get the 1l of Haldex oil in the Haldex part of the diff (the front) because the old oil was still in there, easy to do and I made the same mistake despite being aware of the possibility and having another forum member on hand as a second opinion.

 

I was partially sighted and working on my back in the gloom and unfocussed, a mechanic with a ramp and workshop lighting does not have the same excuses but many many have made the mistake.

 

Thankfully they should cover it under warranty, if you have any suspicion that they might try to wriggle out take it somewhere else first and get them to confirm that the diff has failed and is dry of lubricant.

 

It does not explain the smell from the front but that could have been a DPF regeneration in progress.

Regarding the smell I don´t think it was DPF, as it filled the whole cockpit and still had the smell a couple of hours later.  

[NorwegianYeti]

10 minutes ago, J.R. said:

 

No but if the Haldex is engaged and the bevel drive box seized, th prop not wanting to turn but the rear wheels turning what would happen is one rear wheel would try to turn backwards while the other is dragged forwards.

 

From what you have said though I'm convinced the diff is destroyed through having been run dry, have you heard increasing transmission noises recently?

 

Many many people have suffered the same after having a Haldex service done by a garage or main dealer.

Hmm it kind off feels like it could be the bevel box reading what you wrote about rotation. 

No, I haven't heard any bad sounds of any sort until this

 

Anyhow very interesting and probably not a 15 min job then...