Technical reverse gear judder

[bankjobbob]

Hi Forum newbie here and as always drawn in with a question, but hopefully as i learn will become an attractive member,
I have a 07 burstner 747 with 85k on the clock as i come on or off the power in sixth gear the gearstick moves up and down a lot
and as i’ve been considering a engine remap though i best get the drivetrain sorted first. reverse gear in these is incredible long and i’ve hated riding the clutch to get up hills or to keep speed down. but i now read that this was something that Fiat addressed at the time and fitted a lower gear on recall if owners badgered them. if i’m having the box rebuilt i’d like to do this mod at the same time, But i can’t find any recent info on google
can anyone here give me any pointers on any of the above?
much appreciated bob

 

[varesecrazy]

Hi
This was common when they were new models..

SEARCH on here is pretty good

Wind back the dates to before 2016,and Advanced search should find relevant posts

 

[varesecrazy]

An example..

Reversing judder clutch | FIAT Ducato

Hi all. When I reverse my Ducato 2.8jtd Burstner motorhome, I get quite a bad judder. Last time it also smelt badly. Is this the clutch slipping. Why only in reverse?

www.fiatforum.com

 

[bankjobbob]

An example..

Reversing judder clutch | FIAT Ducato

Hi all. When I reverse my Ducato 2.8jtd Burstner motorhome, I get quite a bad judder. Last time it also smelt badly. Is this the clutch slipping. Why only in reverse?

www.fiatforum.com

Thanks for taking the time to reply
i will have to school myself better
on the the forum search, i have looked but can’t find the golden
post “this firm , these parts “
best regards bob

 

[varesecrazy]

Thanks for taking the time to reply
i will have to school myself better
on the the forum search, i have looked but can’t find the golden
post “this firm , these parts “
best regards bob

Use Advanced SEARCH

I used "reverse judder". As a term

 

[gm6vxb]

I would suspect part of the problem is the bottom engine mount, but could be wrong.
An easy check is with the engine off and out of gear, try to see how much movement you get by trying to rock the engine backward and forward.
If you do notice movement, then you probably have the older bottom mount which was weak and helped to cause judder and
noticable gear lever movement when driving.
Also check the top mounts as these can start to fail with age.
I think now, all engine mounts will be of the newer type, but probably part numbers (early to later) would need to be checked.

A stronger mount was introduced in 2008'ish by FIAT and did make a difference, BUT, the reverse gear ratio was far too high. Very roughly
it works out at about 8MPH when engine revs are around 1000RPM. Now try to reverse at 1-2MPH and you have to slip the clutch. Fine on the
flat but up any slope and you get judder caused by the dual mass flywheel and weak engine mount. There have been cases when some have
broken the gearbox so not good.
At the beginning of the problem, FIAT basically said 'Keep rev's around 1500RPM and slip the clutch when reversing', hence some people burned out their clutch, or broke parts in the gearbox.
So FIAT's fix was firstly to replace the bottom engine mount with a less supple type, and if there were still problems, replace the reverse gear with a lower
ratio one.

I have replaced the bottom mount on my 2007 MH and it does make a difference both reversing and normal driving. Only downside is that there is slightly
more engine noise/vibration, but you get used to it pretty quickly.
Never bothered with the lower ratio reverse gear as I am pretty careful reversing.

 

[bankjobbob]

I would suspect part of the problem is the bottom engine mount, but could be wrong.
An easy check is with the engine off and out of gear, try to see how much movement you get by trying to rock the engine backward and forward.
If you do notice movement, then you probably have the older bottom mount which was weak and helped to cause judder and
noticable gear lever movement when driving.
Also check the top mounts as these can start to fail with age.
I think now, all engine mounts will be of the newer type, but probably part numbers (early to later) would need to be checked.

A stronger mount was introduced in 2008'ish by FIAT and did make a difference, BUT, the reverse gear ratio was far too high. Very roughly
it works out at about 8MPH when engine revs are around 1000RPM. Now try to reverse at 1-2MPH and you have to slip the clutch. Fine on the
flat but up any slope and you get judder caused by the dual mass flywheel and weak engine mount. There have been cases when some have
broken the gearbox so not good.
At the beginning of the problem, FIAT basically said 'Keep rev's around 1500RPM and slip the clutch when reversing', hence some people burned out their clutch, or broke parts in the gearbox.
So FIAT's fix was firstly to replace the bottom engine mount with a less supple type, and if there were still problems, replace the reverse gear with a lower
ratio one.

I have replaced the bottom mount on my 2007 MH and it does make a difference both reversing and normal driving. Only downside is that there is slightly
more engine noise/vibration, but you get used to it pretty quickly.
Never bothered with the lower ratio reverse gear as I am pretty careful reversing.

Very interesting
so it maybe that if i upgraded the mounts all round the disconcerting
stick movement may go away?
So i’m still left with that horribly high reverse (i once got out the van after reversing up my leveling ramps to a cloud of smoke and a round of applause,Spa F1 )
i don’t want to wait till the clutch fails to replace it , Im thinking 85k might be the mark?

 

[rayc]

Very interesting
so it maybe that if i upgraded the mounts all round the disconcerting
stick movement may go away?
So i’m still left with that horribly high reverse (i once got out the van after reversing up my leveling ramps to a cloud of smoke and a round of applause,Spa F1 )
i don’t want to wait till the clutch fails to replace it , Im thinking 85k might be the mark?

Can you confirm which size engine you have 2.3 or 3L? I think your photo shows 160 bhp and if so it will be 3L. Fiat provided 'interventions' , as they called them, for the 2.3 but there were none for the 3L presumably because of the low number involved compared to the 2.3. I also believe there was not the physical room in the gearbox to install a replacement reverse gear.
Engine Thump on Start Up was a 'characteristic' of the X250 on its introduction in 2008. motorhome forums were full of it plus the 'Reverse Gear Judder' and 'windscreen scuttle leaks'. The link below it to one of thousands and is particularly applying to the 3L and the engine thump. https://www.motorhomefacts.com/threads/thump-on-start-up.61898/#post-589555

 

[gm6vxb]

Adding to Rayc's comments, the 'thump' was due to a too weak bottom engine mount letting the engine move. The noise was actually from the exhaust moving on it's mounts.
Windscreen leaks are still common today. Have described how to fix in other posts. Needs a good dry day to cure.
Did find a link to fixing the reverse gear ratio, but definately a proffesional workshop job rather than my kitchen table !.

 

[bankjobbob]

thanks Ray
yes it’s the 3lt and if i’m right that makes it a M40 gearbox, i’ve seen in my searches comments saying that on this box there’s no room for the bigger reverse cog , but then i’m see people saying that they had it done on 08 vans like mine which would have to 3lt
if i end up have to ride the clutch to reverse at sensible speeds so be it. But if there was/is a fix i’d really like to find out
all the best bob

Adding to Rayc's comments, the 'thump' was due to a too weak bottom engine mount letting the engine move. The noise was actually from the exhaust moving on it's mounts.
Windscreen leaks are still common today. Have described how to fix in other posts. Needs a good dry day to cure.
Did find a link to fixing the reverse gear ratio, but definately a proffesional workshop job rather than my kitchen table !.

Thanks for your input
i’m not suffering a thump
my only concern is the stick movement in 6th and the fact that i have to burn the clutch when reversing
But i’m dead interested in the link you found for the reverse gear fix
can you please send me the link?
best regards bob

 

[Ocwobio]

If it's any consolation, I have the older 2.8JTD in my Burstner, and the reverse ratio in that feels higher than first gear! I'd love to have it lower, rather than burn a clutch or launch the damn thing!

 

[Communicator]

If it's any consolation, I have the older 2.8JTD in my Burstner, and the reverse ratio in that feels higher than first gear! I'd love to have it lower, rather than burn a clutch or launch the damn thing!

@Ocwobio you are correct. I have peeled a layer off your eLearn onion. Result attached.

To me reverse is a manouvering gear. I have never understood why modern vehicles have it higher than first gear. I am old enough to have overheard tales from the ealier days of motoring, when it was not unknown to ascend a hill in reverse, if it could not be managed in first gear.

Edit. I forgot the attachment.

 

[Reg 65]

As rayc says, there wasn't the room in the gearbox for a bigger reverse gearwheel.
So the ultimate fix involved fitting a new gearbox casing as well as a new reverse gear wheel
Obviously Fiat were not keen to go to that sort of expense so you had to keep hounding them.
They would try every cheaper 'fix' first - like the software update.
And finally, if you complained enough, and had been through all the other fixes, you would get a gearbox that had been stripped and rebuilt in a garage - so it wasn't put together in factory conditions.
So I didn't bother asking for the fix for my 2008 X2/50 as my van only ran at about 3.3 tonnes.
Even so I dreaded going down steep hills in case I couldn't get through and had to back up.
If I had been towing at the plated 6.5 tonnes gross train weight it would have been hopeless trying to reverse uphill.
But with my 2021 X2/90 I have no worries at all about reversing.
Its the only thing I like better about the new van (The cab parcel shelf and central glove box is no longer standard, and I have had a lot of bother with all the modifications for Euro6)

 

[Ocwobio]

@Ocwobio you are correct. I have peeled a layer off your eLearn onion. Result attached.

To me reverse is a manouvering gear. I have never understood why modern vehicles have it higher than first gear. I am old enough to have overheard tales from the ealier days of motoring, when it was not unknown to ascend a hill in reverse, if it could not be managed in first gear.

Edit. I forgot the attachment.

I'm old enough to have heard that too- indeed I have had to resort to doing so! In my 59 Heinkel 200 bubble car, up a long fairly steep bank somewhere in Shropshire. We were 2 up and full of camping gear, and reverse just about did it, as first definitely would not. Back then (early 80's) traffic was fairly light at the time! However, my Messerschmitt had access to all 4 gears in reverse, as you stopped the engine and started it up backwards for reverse. Certainly an education, but I never got beyond 3rd gear with it.

 

[rayc]

Reminds me of that great film Ice Cold in Alex where they got the ambulance up the sand dune backwards by taking the spark plugs out and using the starting handle to turn the engine with the gearbox in reverse.

 

[bankjobbob]

well i’m starting to think that i will just be riding the clutch when reversing which is a bit annoying, So for now i’m concentrating on the 6th gear stick wobble. i found the mystery part that came with the van, i guess it’s not the dog bone but it’s connected to it ( feel a song coming on)
got the old bits off the van and will order up new mounts top and bottom . if this cures the stick wobble then i’ll leave the box alone and just try and find heavy duty clutch unit to fit

 

[bankjobbob]

So fitted both new bottom mounts today and it has vastly improved the amount of movement on the stick in 6th gear, i haven’t investigated the engine top mounts yet would your thoughts be if i changed these that it would improve it further?
Now i minded to leave the box as is, As fitting a lower reverse gear in this model doesn’t seem possible.
I still fancy fitting a new heavy duty clutch, does anyone have any recommendations on this please?
thanks for your advice so far, much appreciated
bob