sprinter 4x4 vibration!

[paul67]

hello Lady's and gentlemen, I am hoping someone may point me in the right direction as I have searched threads and sites for an answer. I have a 2012 sprinter 4x4 516cdi 5t lbw van.
After adventuring off in to the sticky muddy fields on two occasions I have ended up with a server vibration! I have checked wheels for loose nuts, mud in rims, wheel balance, drive shafts for any obvious damage or ware. the vibration happens at any speed or in any gear but only between 2000rpm and 2800rpm! and only under load, if I back off the accelerator it goes away or if you too the clutch it also goes away as soon as you applie them again it comes back until youbare out of the rpm range, would any of you fine people have any idea? very many thanks, Paul.

 

[M80]

Dual mass fly wheel?
Engine mounts?

 

[paul67]

Dual mass fly wheel?
Engine mounts?

hmmm! I was thinking fuel mass fly wheel as I should have turned the traction control off going into the fields, the more I accelerated I guess the more the brakes came on to stop wheel slip putting more strain on the dual mass fly wheel, both occasions it was under lots of load getting in to the fields with a full payload. many thanks for your diagnosis, very much appreciated.

 

[paul67]

Dual mass lol, predictive text!

 

[M80]

I hadn't considered the traction control effects.
Have you possibly over heated a disc/s and warped one.

Try gently applying some brake pressure while it's vibrating, and still under load (so possibly better up hill).
See if that eliminates the vibes some.

 

[oigle]

I'd suggest it is more likely to be an engine mount issue with the consequent misalignment of one of the drive shafts, probably the front one. They are very sensitive to horizontal alignment.

Ian.

 

[paul67]

I hadn't considered the traction control effects.
Have you possibly over heated a disc/s and warped one.

Try gently applying some brake pressure while it's vibrating, and still under load (so possibly better up hill).
See if that eliminates the vibes some.

Many thanks for the suggestion 're discs, I took the van out for a drive and applied brakes, all very smooth with no feedback through the peddle. I did replaced all the discs and pads after the first muddy field encounter as it was due mot a few days after. The vibration was no different after replacing them, vibration was still creeping in at 2000rpm and disappearing at 2800rpm under acceleration, after the second muddy feild expedition and once back on the road the vibration had nearly doubled. The clutch has no sounds emitting from it at all, no rattles or bangs of any kind, still feels smooth through the clutch pedal. I will check engine and gear box mounts in the morning, I did give the rear of the gear box a little push upwards when looking around the other day and noticed I could move it in the vertical quite easily, not sure how much movement is acceptable but I guess if this is weak it would alter the alingment of the drive shaft faces from gear box to transfer box which I'm lead to believe is the most sensitive to being out of alingment. many thanks again for you time and suggestions I really appreciate your help. Paul

 

[paul67]

I'd suggest it is more likely to be an engine mount issue with the consequent misalignment of one of the drive shafts, probably the front one. They are very sensitive to horizontal alignment.

Ian.

Hi Ian, many thanks for your suggestion, I have just replied to m80 after he suggested possible disc warp due to traction control kicking in, I do think now after some suggestions posted that it is possible drive shaft, gear box to transfer box miss alingment or a engine /gearbox mount. I will check in the morning to see if I can see anything. very many thanks for your suggestions, all very much appreciated. Paul

 

[paul67]

Hi all, just thought I would put an update re vibration problem on sprinter 4x4.

As of today we have checked brakes, drive shafts and joints, engine mounts and gear box mounts. we have fitted a new clutch and duel mass fly wheel as the old unit was on its way out and had quite a bit of play in it.
Sprinter then taken out for a test drive, no change in vibration!
The garage have disconnected prop shafts front and rear to try and isolate problem and cannot reproduce the vibration with the wheels lifted off the floor in any configuration. they have reported that the transfer box is noisy and had difficulty getting the 4x4 system to engage.
I know the alignment of the front prop shaft are critical and I have asked them to check this as a priority but would anything in the transfer box cause a vibration at 2000-3000rpm only under load and any gear or road speed when this is disengaged ?

All suggestions greatly received and much appreciated.

PS as you can probably see in my profile pic the vehicle is operated as a fire and rescue vehicle to support medivac flights remote area fire fighting with the fire service and supporting fire fighting helicopters as well as many other good causes. this down time if frustrating and getting expensive, again all info is appreciated.
many thanks, Paul

 

[M80]

Maybe you've been there, maybe it's a dumb thought,
could a duff injector cause an imbalance / vibration?

 

[paul67]

Maybe you've been there, maybe it's a dumb thought,
could a duff injector cause an imbalance / vibration?

Hmmm! I had this conversation with the garage as its something they had suggested, so on that we sent the van out with diagnostics plugged in and two mechanics, all showed up as working ok on the pc.
I'm not sure if this is 100% way of testing other than pull them out one by one.
Many thanks for your suggestion, maybe the diagnostics don't pick everything up?

 

[LostKiwi]

So this is an engine speed related issue not a road speed issue. This says the issue is before the gearbox.
I would focus attention on engine mounts (they are usually hydraulic and have a habit of losing the oil) or gearbox mounts. If still doing it start looking for a possible misfire.

 

[M80]

I'm no expert but I've read here that diagnostics kit might well show up a discrepancy on the injectors. If honest while I might be shown figures that show one to be out I wouldn't know what it means.
A leak off test is the more basic test, and I can understand that.

 

[M80]

If the mounts are like the Vito, they're just rubber. Top mount, bottom mount and solid rubber in between.
I've a Febi in front of me and the Lemforder I fitted last year were the same.
Who knows mebees some hydraulics would mean no vibes for me.

 

[paul67]

When I have looked at diagnostics and values they all move around too much for me, I would rather hit something with a hammer to fix lol. I might suggest they pull them out and do a proper test to check them, Would be cheaper than replacing them all at the moment
The engine mounts on mine are also of solid rubber and they have all been checked so it seems they have been taken out of the possible cause, or you hope to think! hydraulics does sound a good way to go though. thank you for your replys.

 

[paul67]

So this is an engine speed related issue not a road speed issue. This says the issue is before the gearbox.
I would focus attention on engine mounts (they are usually hydraulic and have a habit of losing the oil) or gearbox mounts. If still doing it start looking for a possible misfire.

Hi LostKiwi, Many thanks for your reply, I have had the mounts checked on both engine and gearbox and all seem in good condition and the garage have had the vehicle up on stands in gear with engine running and in gear trying to replicate the vibration to no avail. mounts have been pushed, pulled and leaverd to check they are good.
van has been out today with two mechanics and diagnostics pluged in to see if they could pick any misfire or possible injector problem but all cam back with no problems showing on the system apart from needing a 're gen! they think possible transfer box problem but like you have mentiond it does sound to be more engine side. the vibration feels like a out of balance wheel through the floor but again not road speed related only engine speed? its a hard one to pin down.
really appreciate you posting as I'm sure it all throws light on possible other problems for owners with similar issues. many thanks, Paul

 

[paul67]

just to add, the van runs very clean with no puffs of smoke or anything, if I had seen any signs of white smoke I would be straight to the injectors but all runs good.

 

[LostKiwi]

This will probably sound weird but check exhaust mounts, particularly around heavy items like cats, DPFs and silencers.
A bad mount can set up resonances at certain speeds.

 

[paul67]

This I will do and thank you. i feel I'm leading the garage with all the help I'm getting from everyone. thank you.
They are good garage and a specialist on sprinters but mine is the only 4x4 sprinter they have worked on anything else Its been in for has been with very quickly and professionally. cheers.

 

[oigle]

TO CHECK THE REAR GEARBOX MOUNT, YOU SHOULD HAVE IT ON A LIFT WITH BRAKES ON AND LOAD THE SYSTEM THROUGH THE CLUTCH OR AUTO AND SEE HOW MUCH DEFLECTION YOU ARE GETTING UNDER LOAD. MOUNT NEEDS TO BE POSITIONED TO MINIMISE DEFLECTION FROM STRAIGHT AHEAD. SORRY ABOUT CAPS!!