Hi all, my 2015 Scout has developed a significant vibration from the drive train. Usually manifests at around 55mph and stays through to 70mph. It doesn't change if I dip the clutch and coast with the engine at idle, so I'm confident it's driveline.

I got the tyres checked and balanced,  can't find any play in the wheel bearings or prop shaft, some minor cracking around the prop donut but nothing significant. Sounds worse at the back of the car. Diff oil level is correct, haven't checked the Haldex yet but it was serviced last year. 

 

My question...... can I whip the rear driveshafts out and run with the propshaft off, just FWD? This could rule more things out before things get spendy. 

I have also considered this for when/if my differential whine becomes catastrophic, I ran a Suzuki SJ410 for a week in FWD only for the same reason.

 

I theorised that it was a no go, assuming the driveshaft removal did not affect the rear wheel bearing pre-load (which I think it would) the rear wheel speed sensors would no longer work which would disable loads of systems like ABS etc and light up the dashboard like a christmas tree.

 

Propshaft removal is preferable but you probably already know that cant be achieved without moving the engine forwards.

 

Vibration likely to be the propshaft guibo coupling, centre bearing or balance.

 

Noisy diff is likely to be the LH (smaller) output shaft bearing.

Edited 11 February, 20251 yr by J.R.

I had a smiliar problem, and I had faulty joints on all drive axles. 

 

Problem was terrible under load, but less noticable in lower speeds and when coasting. 

 

All 8 joints on drive axles were completely dry and no grease letf at all. There were only pin hole sized damage on them.

 

I still have a slight vibration left, but it only occurs when engine and gearbox is cold and around 65-85km/h.

Edited 12 February, 20251 yr by Steinrawr

Thanks guys. Steinrawr, is this what we'd call the  drive shaft CV joints? 

 

12 minutes ago, DuncanDisorderly said:

Thanks guys. Steinrawr, is this what we'd call the  drive shaft CV joints? 

 

Yes! CV-joints. 

 

For me it was way easier and cheaper to replace the axles as a whole rather than fixing all the individual joints. 

Thanks amigo, I'll check that next when I get home next week 🙂

Well, some answers but more questions....

The guibo coupling, the rubber condition doesn't concern me, but I've found today that the outer metal ring is not securely attached anymore. I can move the ring a good few mil back and forth, and it's actually clunking back nd forth on the rubber, not just the rubber flexing.

So first question... as I understand it, the metal outer ring is just a damper, can I cut it off? Other cars don't have that outer ring. Or will running like this lead to a propshaft through the diesel tank?

Second question, searching for the coupling part number (5Q0 521 307) shows the price around £170, but also throws up loads of hits for the A3/Q3/Golf/Tiguan coupling with part number 1K0 521 307, for about £65. Everything I can see in the specs for each appears to be identical, look the same, same diameter etc etc. Interchangeable?

I've got a short video of the play but it's too big a file to upload.

Edited 18 March, 20251 yr by DuncanDisorderly

36 minutes ago, DuncanDisorderly said:

So first question... as I understand it, the metal outer ring is just a damper, can I cut it off? Other cars don't have that outer ring. Or will running like this lead to a propshaft through the diesel tank?

The outer ring plays no part in the transmission of drive it is simply a harmonic damper, I fully intend removing mine with a disc cutter when it gets as bad as yours, in fact I might do it pre-emptively before the next contrôle technique as I'm getting fed up with showing the testers the new unfitted one to prove that what they think are splits in the coupling are moulded in from new.

Without the ring it will be the same as the Rotoflex couplings on my Lotus Elan, well a lot better actually because they have been made of cheese for the last couple of decades. Also there is an inner steel ring that totally encloses the Guibo drive coupling.

I just looked for a part number on my coupling on the shelf, its a pattern part but the number if its of any use is G2N21PC0810-07420923A-0847

Google shows my part to be this which has the 1K0 part number referenced and says its will fit MK2 Octavia 4x4 and my Yeti, I'll be pi55ed if it doesn't.

To anyone else reading this, has anyone successfully replaced one of these couplings by dropping the centre prop bearing and persuading the old and new couplings into/out of place with leverage without moving the engine and transmission forwards?

It's that which has made me put off the job for so long.

Thanks JR, I'll cut that ring off and see if that cures the driveline vibration.

For the propshaft, I had a good look today whilst I was underneath, I don't think dropping the centre bearing alone will give enough play.

That said, it only needs the bottom engine mount undoing, with the engine and box hanging on the top mounts the bottom of the sump can be swung forwards the couple of inches needed to clear the back of the prop. 2 person job, but looks quite do-able.

Let us know how you get on, don't be surprised if the vibration worsens, after all the outer ring is there to damp vibrations.

That said I would not want the thing flailing around and clattering as it is.

Cut the ring off today, was only attached by a few buts of rubber. Took a Stanley knife to the inner metal ring to get all the rubber blocks off, nice and tidy.

Test drove, not a dot of difference 😅

Would say it's marginally better, but only just.

Although that damper ring was loose, it wasn't the source of the drone noise.