Hi ya,

Car is still under JLR warranty but trying to replicate or point them in the right direction rather than fobed off with “can not replicate the issue”
When I drive off in the morning, not straight away but as I start to pull up a hill, there is a thud from the back. Today it seemed to do it after I had reversed outside a shop then driving off again.
Any ideas?

…………. “If it ain’t broke, don’t fix it” -where’s the fun in that?

Last edited by Gremlin500 on 9th Apr 2024 10:11pm. Edited 1 time in total

I thought that but struggling to recreate it. Is there a way I can replicate it?

If you can't replicate it reliably, how do you expect the dealer to?

Yeah exactly. That’s why I am looking for ideas of what it could be to see if I can replicate if it’s a certain fault. Like if it’s fuel slap, what is the best way to replicate the fault

Well firstly, not everything is a 'fault', sometimes vehicles have certain characteristics in the right (or wrong) circumstances - you also need to be careful of confirmation bias, that is, you or the internet have decided what the cause of the concern is and set about to prove it... down entirely the wrong rabbit hole.
Secondly, keep an open mind, make absolutely sure there's nothing of yours rolling around, spare wheel is fixed down etc. and document as much as you can the circumstances of when it occurs (time of day & weather, engine revs / road speed, inclination / declination of surface change in gear or direction of travel, indicated fuel load, number of persons on board, external and commanded internal temperature etc.) Some may not be relevant to the final diagnosis but without as much telemetry as possible it would leave 'guesswork' as part of the investigation of the concern.

Here's an example from a few years ago:-
Concern raised was an audible 'clunk' when setting off in the morning from drivers home address, can sometimes be felt through the steering.
Vehicle was checked over and kept for a week, left standing during the day so it could be checked in the mornings - nothing, even when parked on the demonstration ramp as the driver mentioned he had a good slope on his drive.
No parts were changed as everything was in spec. and playing 'parts bingo' wouldn't be claimable whilst it could be seen by the driver that we 'thought there was a parts issue'.

In the end, I went to the drivers house and observed him starting and driving the metre or so before the 'clunk' which did exist, even though we couldn't find the cause - which we never would have because it was a loose paving block on his drive...

So the concern was 'real' but the cause was external, even though it changed the vehicles behaviour.

Hi ya,

Fully agree with all you say. Just so you guys know, had many, many RRS etc and I also now design cars etc coming from many years of starting at production, worked my way up. It’s not a normal noise, and had already checked the obvious, loose spare wheel, wheels tightened etc. sound is from rear axel area so could be fuel slap or a drive train issue. If there are some known previous issues with obvious repeatable checks I.E reverse to forward, or setting off on a hill, or turning on a slope etc. I tried flooring it from stand still and didn’t do it, going backwards then straight to forwards, didn’t do it. Does it in different areas so not due to a road issue etc

If the car going up the hill involves a downshift, and/or extra acceleration on your part, it might need the gear change software update. Search for threads on that. The issue is that the gear does not come in quickly enough and when it does, the revs are higher and it sends a thud down the driveline. Mine had this and the software update cured it. Note the update is not something done on normal services, it is only for cars that thud on kickdown. There is, I think, a 'service bulletin' on the topic to which you could refer your dealer.

It does not always do it, and "flooring it from standstill" is not the right test, it is used by dealers for a different problem which I think some 322s had where the driveshaft could hit the underside of the car. It was tried on my car and the thud didn't happen. Only Range Rovers since 1988

Last edited by CS on 26th Aug 2022 7:11pm. Edited 1 time in total

Hi ya, will try a kickdown down tomorrow, that’s an easy thing to try but good shout

………. “If it ain’t broke, don’t fix it” -where’s the fun in that?

Last edited by Gremlin500 on 9th Apr 2024 10:10pm. Edited 1 time in total

Lol at todays prices, not that simple lol but yeah if that would test it out

could be this,

https://www.fullfatrr.com/forum/topic37809...=fuel+tank ... - .- -.




Y. O. L. O.
.

Yeah the fuel slap issue. Sounds a very good shout. Will see if I can cause the sound tomorrow and Sunday. Will then fuel up to the brim and try again

………. “If it ain’t broke, don’t fix it” -where’s the fun in that?

Last edited by Gremlin500 on 9th Apr 2024 10:10pm. Edited 1 time in total

Well you live and learn. Mine does this very occasionally as I drive away from the end of my driveway or at roundabouts. I thought it was something loose in the boot  FFRR SDV8 Autobiography