Can any forum member shed any light on the issue quite a number of owners of motorhomes based on the latest generation of the Fiat Ducato light commercial vehicle are experiencing when reversing?

My new Ducato X250 has the 3 litre,160 bhp motor and manual gearbox. When reversing at tickover speed there is a noticeable vibration transmitted into the body structure. Whilst unusual, the vibration is contained and of limited amplitude, and there is no evidence of violent rocking of the engine/gearbox unit or gearchange mechanism. Some owners believe it is clutch judder and is damaging. Fiat describes it as a "characteristic" of the engine and drivetrain and advises increasing engine revs to about 1200 to 1300 rpm. This works, but reverse gear is quite tall, and who wants to reverse a 3.5 tonne vehicle with limited rearward visbility at anything other than a slow walking pace? Slipping the clutch results in a burning smell if used for more than a short distance, especially uphill.

There is no problem when starting off at tickover speed in either first or second gears. First gear is lower than reverse but second gear is higher, but there is no vibration similar of the kind that occurs when reversing. Whilst unusual and therefore disturbing , my main concern is whether this vibration is indicative of an underlying problem that could result in premature failure of the clutch assembly or gearbox. There has also been much debate on the internet motorhome forums on this subject, but no-one has been able to offer a technical explanation of what is causing the behaviour when reversing.

There has been even more discussion concerning the 2.3 litre, 130 bhp engine, which seems to have an even bigger issue, This does seem to be clutch judder that affects some but not all vehicles. For the 2.3 Litre engine, Fiat's (reluctant) response has been a three-stage programe of modified engine management software, stiffer engine/gearbox mounts and, finally, fitting a lower reverse gear set. Often, the complete clutch assembly has been replaced as well. These modifications are reported to work. However, no modifications are offered for the 3 Litre, 160 bhp version.

Any light anyone can shed, or any advice, will be appreciated.