Driveline Grumble or Groan in 5th 3.0 D4

[Talby]

Hi All,
My 2011 D4 3.0 has a driveline noise when in 5th gear at 1400 rpm on medium acceleration on flat roads!

The noise will get louder if I accelerate harder

Being in command shift 5th at a low speed might be the cause but it doesn't do it in any other gear.

Just wondering if anyone else has had the same problem? Or maybe able to run their vehicle in 5th and accelerate to see if it's just a mechanical sound at those revs and speed?

I dropped it into my local dealer and took the mechanic for a quick run and was able to replicate the noise with him in the car ( which was a relief ). You know how it goes you get a rattle or noise take it to the mechanic and they can't find it!
The mechanic wasn't sure what it was so will need to book it in for further investigation.

Thanks,
Talby.

[jonesy63]

Hi Talby - how many KM are on your D4?

[Graeme]

Is there dirt/mud on the gearbox shield high enough to be interfering with the exhaust pipes?

[Epic pooh]

This probably isn't your problem and probably isn't good for your blood pressure, but my failing diff started out only audible as a kind of groaning noise in 5/6 gear ... have them scope that out if they hit a wall ... !

[Talby]

Hi guys,
Thanks for your replies
There is only 20,000 kilns on her.
Definitely no mud and reaching for the blood pressure tablets now!
Warranty runs out in August so need to get it sorted
The sound is almost like a slipping clutch!

[sniegy]

What tyres & how many K's?

Cheers

[Talby]

Hi,

I've got the factory Goodyear wrangler. 20,000km on the clock.

Is anyone able to replicate this noise in their d4?

Talby

[unseenone]

I talked with my guys, who rebuild these transfer boxes, transmissions, etc. and they suggested it sounds like the torque converter based on your symptom description. The TDV6 are know to have a lot of issues with these as well.

I hope this helps.

[Talby]

Thanks Unseenone,
I will pass onto the mechanics, would it be worth trying to get them to change the trans fluid?
Talby

[Graeme]

Hi All,
My 2011 D4 3.0 has a driveline noise when in 5th gear at 1400 rpm on medium acceleration on flat roads!

The noise will get louder if I accelerate harder

Being in command shift 5th at a low speed might be the cause but it doesn't do it in any other gear.
.....
The sound is almost like a slipping clutch!
.....
20,000km on the clock.

Without having had the opportunity to see if mine does, I wouldn't be surprised if the torque converter is unlocked due to the load at the revs in that particular gear. Applying the same throttle opening in 6th at the same engine revs is likely to produce the same results. I use low revs regularly (get down to 1000 even without command-shift depending on the gear) but let the revs get higher when wanting the engine to work harder. I have my version of flappy paddles that I use almost entirely to upshift well below 2000 rpm.

I'll test mine next time the engine and gearbox have had a chance to warm-up.

[Graeme]

I tried it, a couple of times, even though I suspected the oils weren't up to temperature but couldn't induce any noticible slip with increasing throttle from 1400 rpm. On 1 occasion kick-down to 3rd occurred at around 1800 rpm at or close to full throttle but no slipping prior to kick-down. Being a dirt road there was some tyre noise but normally being very aware of any torque converter slippage I considered there was nothing significant in this exercise. 135K and still haven't changed the gbox oil.

[Talby]

Thanks Graeme,
The noise I am getting is in command shift/manual in 5th gear not when in auto.
Thanks for trying it in your vehicle, it would be interesting if it happens in yours!
Talby

[unseenone]

Thanks Unseenone,
I will pass onto the mechanics, would it be worth trying to get them to change the trans fluid?
Talby

I doubt it, if it turns out to be bad, it is bad. There are reman ones on the market, but if it is under warranty, it seems like they just need to diagnose it and fix it up.

Perhaps it might be a worthwhile effort to have the fluid analyzed though.

Probably they should fit a set of chassis ears on it, and run it through the paces as well. Sound travels through the frame on these, and it can be difficult to pinpoint problems without it sometimes.

[Graeme]

Thanks Graeme,
The noise I am getting is in command shift/manual in 5th gear not when in auto.
Thanks for trying it in your vehicle, it would be interesting if it happens in yours!
Talby
My test was in command-shift 5th.

[Talby]

Thanks Again Graeme,
I forgot the transmission can override your gear selection if required.
Looks like mine has an issue, goes in Thursday morning !
Cheers Talby.

[baldivistribe]

Hello
Made the mistake of trying it with ours, my goodness what a racket. Don't like the sound but have no idea what or where its from.
Cheers
Steve

[Graeme]

Mine normally makes an induction racket on significant throttle at very low revs - around 1100 rpm in manual mode, but didn't starting at 1400.

[letherm]

Mine normally makes an induction racket on significant throttle at very low revs - around 1100 rpm in manual mode, but didn't starting at 1400.

Apologies if this is slightly off topic.

Hi Graeme.

What do you mean by induction racket. The reason I ask is that I've noticed what I would call a labouring sound/feeling as though the car needs to change down but hasn't. Funnily enough it is at 1100 rpm hence this question. Mine happens if I am cresting a rise or slight hill in auto and I was wondering if it's the auto not downshifting as it maybe should. I first noticed it with cruise control on but it does it with it off too. I am not accelerating or anything just keeping the throttle steady and if I push the accelerator it downshifts or if I use the paddle and manually downshift the grumbling goes away.

Martin

[Graeme]

I expect mine's induction noise is from turbos working overtime coupled with having a snorkel fitted so that the induction noise is just outside the window. Labouring/vibration at 1100 rpm is not unexpected considering the crankshaft is turning at less then 20 rpm / 60 combustions per second - rather like the 50Hz hum from household electrical devices. These engines seem to be willing workers at low revs but I try to avoid other than light loads, keen not to decrease longevity from possible excessive bearing and piston skirt/bore loads.

[baldivistribe]

I think at 1100rpm your crank is rotating at more than 20rpm.

[gordo 350]

at 1100 rpm isn't it doing 1100 rpm ?

[jonesy63]

1100 rpm = (1100/60) rps = 18.33

[Graeme]

Yes, 20 / sec is what I meant to write.