Member Since: 14 Apr 2008
Location: Windsor - UK
Posts: 356
Large "thump" when accelerating after decelerating ....
Hi all
For instance when reducing the speed to wait for the traffic light to change, just slowing down not stopping, and then accelerating (not hard) when the light goes green, I feel/ hear a large thump, which I believe is coming from the back.
Both diffs have new oil (year old), gearbox and transfer box with fresh oil (2 weeks). By the way this is not new, I thought the gearbox and transfer case oil change would solve the issue but it didn't.
I'm thinking propshaft?
Thanks
LucioI'm riding a R1250GSA Triple Back
Previous love: Disco 3 HSE MY07, D4 heated Steering/W, D4 rear cluster, D4 extended roof rack, D4 grille & air grille, D4 rear bumper, colour coded arches + front bumper, side-steps, Webasto timer/ remote control, De-Tangoed Xenon headlights + HID, LEDs all around, reverse CAM (RR hack) + brightness, DLR LEDs, 3-click indicator, SatNav on the move, EGR's done, front/rear antiroll bar Polybush, gearbox pan/filter + oil mega-flush.
3rd May 2016 5:59 pm
M3DPO
Member Since: 22 Sep 2010
Location: Notts.
Posts: 8219
What mileage?- all autos seem to do it after 70k miles including buses. I too would like to know the cause.It can when others can't,
It will when others won't,
It goes where others don't.
3rd May 2016 6:14 pm
CFB
Member Since: 02 Dec 2005
Location: Bradford, West Yorkshire
Posts: 6100
Mine does it (D4) around 68k miles, feels like slack in the transmission being taken up from the prop or diff, but doesn't always do it if I am gentle on the throttle so maybe more of a torque convertor issue (if that's possible??)
Not great for a vehicle of this calibre really. Not sure there is much that can be done and mine has an extended LR approved warranty.2020 BMW X1 18d XDrive X-Line Auto
3rd May 2016 6:31 pm
Disco_Mikey
Member Since: 29 May 2007
Location: Dundee, Scotland
Posts: 20831
New gearbox and TC, new transfer box, rebuilt front diff, new rear prop, and it still does it
The only saving grace is they were all for other reasons My D3 Build Thread
Member Since: 22 Sep 2010
Location: Notts.
Posts: 8219
I used to put it down to the spline being worn between the torque converter and gear box, but Disco_Mikey has renewed both and he says it still does it, a gearbox reset cures it but it comes back after a few thousand miles.
I sometimes travel on public buses and they all do it when changing down to first gear
Edit: must type faster It can when others can't,
It will when others won't,
It goes where others don't.
3rd May 2016 7:03 pm
mz mini
Member Since: 02 Jul 2014
Location: Sunny Devon
Posts: 1759
It smacks of prop ,prop bearing or diff but if DM says that changing them all does not cure it god knows mine does the same I thought that mine was the prop with a bit of play in it Land Rover 90 - deceased
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3rd May 2016 7:12 pm
luciogodoy
Member Since: 14 Apr 2008
Location: Windsor - UK
Posts: 356
Oh well, it seems that this is yet another landrover mystery that we have to accept!!
Thank you all.I'm riding a R1250GSA Triple Back
Previous love: Disco 3 HSE MY07, D4 heated Steering/W, D4 rear cluster, D4 extended roof rack, D4 grille & air grille, D4 rear bumper, colour coded arches + front bumper, side-steps, Webasto timer/ remote control, De-Tangoed Xenon headlights + HID, LEDs all around, reverse CAM (RR hack) + brightness, DLR LEDs, 3-click indicator, SatNav on the move, EGR's done, front/rear antiroll bar Polybush, gearbox pan/filter + oil mega-flush.
3rd May 2016 8:48 pm
tayaste
Member Since: 15 May 2013
Location: Chester
Posts: 7633
Didn't Pat release a software update a while ago to help reduce this thump?
3rd May 2016 8:53 pm
M3DPO
Member Since: 22 Sep 2010
Location: Notts.
Posts: 8219
Yep! Helps but still returns after a few hundred miles.It can when others can't,
It will when others won't,
It goes where others don't.
3rd May 2016 8:56 pm
luciogodoy
Member Since: 14 Apr 2008
Location: Windsor - UK
Posts: 356
Just to add, I've done a reset and update of the gearbox module, and the thumb is still there!I'm riding a R1250GSA Triple Back
Previous love: Disco 3 HSE MY07, D4 heated Steering/W, D4 rear cluster, D4 extended roof rack, D4 grille & air grille, D4 rear bumper, colour coded arches + front bumper, side-steps, Webasto timer/ remote control, De-Tangoed Xenon headlights + HID, LEDs all around, reverse CAM (RR hack) + brightness, DLR LEDs, 3-click indicator, SatNav on the move, EGR's done, front/rear antiroll bar Polybush, gearbox pan/filter + oil mega-flush.
3rd May 2016 8:58 pm
Disco_Mikey
Member Since: 29 May 2007
Location: Dundee, Scotland
Posts: 20831
Tried gearbox firmware on the original box, with no difference
Above driveline components make no difference
What does make a difference is a Transfer Case Clutch calibration, which lasts around 20 miles, then back to same old
Rear diff is still to be fitted, hopefully before the end of May My D3 Build Thread
Member Since: 22 Sep 2010
Location: Notts.
Posts: 8219
My opinion is it has got to be when the gearbox changes into first gear, probably worn synchromesh, otherwise it would do it at other speeds and gears when braking and then accelerating, it does not do it in sport mode as sport mode does not select first gear when slowing down unless it is selected manually, but this does not explain why DM's still does it.It can when others can't,
It will when others won't,
It goes where others don't.
3rd May 2016 9:07 pm
Disco_Mikey
Member Since: 29 May 2007
Location: Dundee, Scotland
Posts: 20831
Thump is exactly as it was before. Does it in sport and auto modes
I know the rear diff is shafted and noisy, so will see how that goes firstMy D3 Build Thread
Member Since: 16 Sep 2015
Location: Berkshire
Posts: 637
Glad I found this, I had beel looking but could not see a topic for it.
My V8 does this and was cured during flush and reset but has now returned. I had been told by an indie that it could be the early software for gearbox and engine but this thread suggests otherwise?
At least I am not alone! Then again there are rarely new issues here just a common recurring theme?
Member Since: 30 Nov 2014
Location: Southend on Sea
Posts: 180
Same issue on my 70k my09, changed all oils and Geoff. has done gearbox flush. Does seem to vary when it happens, but never consistent.
Sometimes slow right hand turn then left, then in straight line, so struggle with Diff as stress through it would differ in each of the three. The diff is silent so could only really be slack in pinion/crown wheel mating or perhaps in the spider gears, but its not consistent to point to these in my mind.
Doesn't appear to be any slack in prop and central bearing seems good.
So this leaves bushes in the arms and hub knuckle or poss anti roll bar, but there is no knocks or anything when suspension is moving, at least I know I am not alone.
If someone does establish why this is please shout long and hard there are a number who will benefit
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