[gt40]

Hello all.
As the thread title suggests I have a gearbox vibration issue with my 2014 XF 2.0 petrol. 190000 km on the clock (118000 miles). The gearbox operates perfectly from 1st through to 8th however I can feel vibration in 6th gear only and only after I shift from 5th to 6th - if I down shift from 7th to 6th there is no vibration. When there, the vibration frequency varies with speed (and RPM) and disappears as soon as the transmission shifts to another gear or I shift manually. The vibration is also more pronounced under load but is still there when coasting in 6th.

I reset the adaptions using SDD and followed the process to re-adapt which made zero difference. I have read about problems with gearbox mountings and guibo joints but the fact that it only happens in 6th gear and at all speeds, makes these items unlikely candidates. I have not changed the oil yet due to advice I received suggesting not to waste money until someone can hopefully positively say what the problem may be.

Does anyone have any ideas?

 

[TheStig]

The 6HP & 8HP have both proved to be ultra reliable when fitted to the XF & XE so we're unlikely to be your best resource for a diagnosis. Have a scoot around BMW forums because I understand that they have more issues with the 8HP & obviously there are lots more vehicles to go wrong.

 

[Phil1]

If it's only happening in one certain gear regardless of rev range and the others are ok in the same rev range, then I think you've kind of answered your own question.

It would be worth seeking the advice of an independent jaguar specialist though to confirm the diagnosis and probably give you an estimate for a removal, repair/rebuild. They'll probably take it out and either do it on an exchange basis or send it to a gearbox specialist for repair.

I'd agree with not changing the oil yet as it's fairly unlikely to be that and you're potentially just wasting money on a change that you'd potentially get done with a rebuild anyway.

Don't get suckered into using a main dealer as they'll just charge you for a full new gearbox, which will be £1000s. I'm not sure on the current prices but I'd be reasonably confident you'd be able to get one replaced for a reconditioned unit on an exchange basis, or your current one repaired (this will take longer) for £1000-1500 including labour, possibly less.

A good Indy should be able to order one in ready and have it done in a day.

 

[Statler]

Do you know if the oil has ever been changed?

ZF recommend 60000 miles even though Jaguar say it’s sealed for life.

I had the gearbox oil changed on my X250 2.2d at 85000 miles and it made a significant difference.

Changing the oil means removing the combined sump pan/filter which would alllow you to see if there is any metal in it which could point to your issue.

Have look at David’s Range Rover refresh, you’ll see what’s involved.

My 2007 Range Rover Supercharged Project

My 2007 Range Rover Supercharged Project

Rather then having these scattered around the “What did you do today“ thread I thought I’d put them all in one place. 4th Jan New toy arrived today. It was delivered to me as it had a misfire. I also didn’t fancy trailer it 250 miles and trying to cross into England when Wee Nippy it claiming...

r.tapatalk.com

 

[ninjag]

If it helps, I had my ZF8 fluid and sump/filter replaced at just over 70k miles and the fluid was cooked (stank as well), the magnets were coated in a horrible metallic paste and I have nice smooth shifting again.

 

[Phil1]

There's a big difference between having less than smooth changes and having one single gear which judders/vibrates. No amount of oil changes will sort that, there's something wrong with one or more planetaries in the box, probably seriously worn.

 

[Statler]

Might be a blocked or restricted solenoid that is fluttering. Oil change might help.

Either way, dropping the sump pan will reveal nothing or something. Further diagnosis can go from there.

 

[cutlea01]

It all depends how enthusiastic you are on self fixing faults and your mechanical ability and home workshop facilities. You could drain the fluid and drop the sump. This would immediately give you some clues, the fluid may be burnt, the sump full of iron filings or bits of clutch plate etc. But now the car would be immobile, so you'd have no choice but to fit a new filter, sump and refill as a minimum. I'd be tempted while the sump was off, whatever I found, to replace the solenoids then refit and refill, unless of course the amount of debris found indicated the box was clearly internally damaged. If I'd wasted my time and money, then so be it, at least I'd had a go.

 

[idrobbo]

If it's only happening in one certain gear regardless of rev range and the others are ok in the same rev range, then I think you've kind of answered your own question.

It would be worth seeking the advice of an independent jaguar specialist though to confirm the diagnosis and probably give you an estimate for a removal, repair/rebuild. They'll probably take it out and either do it on an exchange basis or send it to a gearbox specialist for repair.

I'd agree with not changing the oil yet as it's fairly unlikely to be that and you're potentially just wasting money on a change that you'd potentially get done with a rebuild anyway.

Don't get suckered into using a main dealer as they'll just charge you for a full new gearbox, which will be £1000s. I'm not sure on the current prices but I'd be reasonably confident you'd be able to get one replaced for a reconditioned unit on an exchange basis, or your current one repaired (this will take longer) for £1000-1500 including labour, possibly less.

A good Indy should be able to order one in ready and have it done in a day.

Or a good gearbox specialist if one exists near you.

 

[Phil1]

Might be a blocked or restricted solenoid that is fluttering. Oil change might help.

Either way, dropping the sump pan will reveal nothing or something. Further diagnosis can go from there.

Highly doubtful. It'll either change gear or not. There won't be an in-between where it's half changing gear/not fully engaging.

 

[gt40]

Thank you for all of the suggestions.
I have been scouring the internet looking for ideas but have not come across anything similar. As mentioned these gearboxes are used on many different make of vehicle so I have been on many different forums but have not found anything that even vaguely matches my symptoms.

I have spoken with 3 different auto gearbox specialists including ZF themselves but none can offer any ideas apart from advising that I take it to them to diagnose. I do all my own work so if it comes to it I will strip the box myself and see what I find or alternatively will fit a good used replacement which isn't difficult if one has the equipment.

If the gearbox had other issues I would have definitely started doing some stripping to see if there is anything obvious but its so smooth throughout the range that I cant help but wonder or hope that it will be something small. I did read about individual solenoids causing strange behaviour but I cant get my head around how it could cause my snag because 6th is the only gear that none of them are energized (apart from the park solenoid).

The thing that throws me is the vibration only being there on the upshift but not the downshift - once the vibration is there on the upshift, it stays till the next shift. I can accelerate and decelerate as much as I want and its there, The same can be said about the lack of vibration in 6th after the downshift - its not like it comes and goes. This means the part that is "imbalanced" is locked into its out of balance condition and cant move till the next shift and vice versa.

I have troubleshooting and overhaul manuals for the 8HP70 which I will continue reading and giving myself headaches. I keep having eureka moments but they only last a few seconds as I continue to read.

I have just had an idea - will do a test drive later and will shift from 5 to 6th while coasting and also try shifting from 7th to 6th will under max load to see what happens. With normal driving the load on the box will be opposite to that so that may affect things.

Not that it will tell me much though but its going to be a nice day for a drive. Sunshine and 30 degrees C. Bliss...

 

[wilf]

Checked the propshaft UJs?

 

[gt40]

Checked the propshaft UJs?

Yes I have. But if it was a propshaft or UJ issue, the vibration will vary with speed in any selected gear.

 

[FCS]

Starting a resonance can be difficult, but when it starts it continues. Wilfs comment above is what I was thinking, ie. it may not be the box, it could be that a resonance is created by a particular set of criteria which then continues.A vibration like that would usually be a bearing or rubber connector or mounting rubber. An unbalanced part would do it all the time at a particular speed. It's a bit like a noise which seems to come from one area but is in a totally different place. Vibrations and noise are the same thing.
Might be worth a look around at some not obvious things before stripping the box.
Faults usually get worse or better they rarely stay the same, so you could wait a while longer to see what happens, it may be easier to find the fault. You don't have a lot to loose, as once you start on the box it will be expensive whatever you do.

 

[gt40]

I have wondered about resonance but I am fairly sure that this isn't the case with my car. (I have not completely discounted it though and will keep it in mind with my troubleshooting). It definitely feels like a mechanical vibration which you get from an unbalanced propshaft of half shaft for example.

I once had a car which had somehow lost the spigot bearing that sits in the end of the crankshaft which locates and centralizes the gearbox input shaft. (who knows how it went missing but that's another story). If one was lucky and you released the clutch correctly the clutch and pressure plate would line up perfectly and there would be no vibration. If unlucky and it did not line up you would get a vibration in time with engine revs which would disappear if you depressed the clutch and may or may not come back with releasing it again. That problem has nothing to do with my current fault but thats what my vibration feels like. When the C, D and E clutches engage as they do in 6th, something is out of line or balance and gets locked there until one or more of the clutches disengages with a gear change and that allows the offending part to spin normally again.

I am trying to find the easy answer and the prop shaft is definitely the easiest to put right but I just cant get it to fit what I am experiencing. On my test drive today I purposely tried different loads on the gearbox so every shift was different but nothing changed. 5th to 6th and the vibration started 100% of the time. Low and high revs and speed, full throttle, partial throttle, you name it.

I am using the car as much as possible to see if things get worse so time will tell.

 

[hamedhbb]

I have wondered about resonance but I am fairly sure that this isn't the case with my car. (I have not completely discounted it though and will keep it in mind with my troubleshooting). It definitely feels like a mechanical vibration which you get from an unbalanced propshaft of half shaft for example.

I once had a car which had somehow lost the spigot bearing that sits in the end of the crankshaft which locates and centralizes the gearbox input shaft. (who knows how it went missing but that's another story). If one was lucky and you released the clutch correctly the clutch and pressure plate would line up perfectly and there would be no vibration. If unlucky and it did not line up you would get a vibration in time with engine revs which would disappear if you depressed the clutch and may or may not come back with releasing it again. That problem has nothing to do with my current fault but thats what my vibration feels like. When the C, D and E clutches engage as they do in 6th, something is out of line or balance and gets locked there until one or more of the clutches disengages with a gear change and that allows the offending part to spin normally again.

I am trying to find the easy answer and the prop shaft is definitely the easiest to put right but I just cant get it to fit what I am experiencing. On my test drive today I purposely tried different loads on the gearbox so every shift was different but nothing changed. 5th to 6th and the vibration started 100% of the time. Low and high revs and speed, full throttle, partial throttle, you name it.

I am using the car as much as possible to see if things get worse so time will tell.

Sorry if you have mentioned it but have you tried changing the oil and pan? If yes, I would check valve body and solenoids first that is accessible easily before taking the box off.
I would check engine mounts as well, specially the one that is effectively gearbox mount on the back of gearbox.

 

[gt40]

Sorry if you have mentioned it but have you tried changing the oil and pan? If yes, I would check valve body and solenoids first that is accessible easily before taking the box off.
I would check engine mounts as well, specially the one that is effectively gearbox mount on the back of gearbox.

I haven't tried changing the oil and pan yet because I dont want to waste the money if it is not related to my vibration. Its another thing that I have not discounted though and will do it before I finally start pulling things to pieces.

I have inspected the engine mountings you mention with particular attention to the gearbox mount and they appear to be ok. I do own another XF with a similar drivetrain so may swap that gearbox mount just to see if anything changes.

 

[gt40]

Thinking about that rear gearbox mounting, if it was torn or soft with age, any small vibration in the gearbox would tend to be amplified if it isn't contained by a firm mounting so its a possibility. Maybe I will throw a new one on anyway. They are not very expensive.

 

[FCS]

Thinking about that rear gearbox mounting, if it was torn or soft with age, any small vibration in the gearbox would tend to be amplified if it isn't contained by a firm mounting so its a possibility. Maybe I will throw a new one on anyway. They are not very expensive.

My point exactly again nothing to loose.

 

[Swindon Andy]

As it's 6th gear only/always, seems to me it must be a gearbox fault. Also doubt it's something an oil change would fix. If I had this problem and couldn't put up with it, I'd go to a gearbox specialist first.