Technical 1995 Ducato gearbox 2.5tdi 20MK20

[aloria19]

Hi Forum

Looking for an old sage that can help me with my Motorhome gearbox.

It's a 1995 Ducato 14 RHD 2.5tdi Sofim with a 5 speed manual box bearing the etching 20KM20.

I know these have issues with 5th.....and there's plenty on here on that subject. However, mine has a bad crunch on 3rd, when approaching from 4th and an (almost livable) crunch from 2nd>3rd. But no gears jumps.

I know the gears are available from Costal Motorhomes and possibly others(?), however, I am trying to find a sound 2nd hand gearbox. Herein lies the issue; there are so many gearboxes used on these vehicles, even this exact model and year range.

Can anyone decode the 20KM20 code? I have found second hand 20KM.. boxes but not direct 20KM20 replacements. Does anyone have a ready reconner of what fits what, and what gearbox is a later (possibly improved) version of the last. Are the final two numbers relevant or are all 20KM"xx" boxes cross compatible?

Going round in circles.....any help / advice would be appreciated.

cheers

 

[aloria19]

Hi Forum

Looking for an old sage that can help me with my Motorhome gearbox.

It's a 1995 Ducato 14 RHD 2.5tdi Sofim with a 5 speed manual box bearing the etching 20KM20.

I know these have issues with 5th.....and there's plenty on here on that subject. However, mine has a bad crunch on 3rd, when approaching from 4th and an (almost livable) crunch from 2nd>3rd. But no gears jumps.

I know the gears are available from Costal Motorhomes and possibly others(?), however, I am trying to find a sound 2nd hand gearbox. Herein lies the issue; there are so many gearboxes used on these vehicles, even this exact model and year range.

Can anyone decode the 20KM20 code? I have found second hand 20KM.. boxes but not direct 20KM20 replacements. Does anyone have a ready reconner of what fits what, and what gearbox is a later (possibly improved) version of the last. Are the final two numbers relevant or are all 20KM"xx" boxes cross compatible?

Going round in circles.....any help / advice would be appreciated.

cheers

To add....

Have heard snippets that the driveshaft sizes can differ across different boxes.
Have heard that after a certain year the position of revers gear changes.
Have heard that the 2.5tdi shares the same box with the 2.8
some say the normally aspirated 2.5 has a different gearbox to the tdi
Size of wheels make a difference?
That I need to match the model "number" (mine is a Ducato "14")

Am I ringing any bells out there?

 

[aloria19]

So, have been in contact with a gent on ebay who is breaking a 1999 Ducato 230 14 normally aspirated 2.8.
This proved to be the wrong box; the clutch actuation fork enters the box from the front, where ours enters from the top.
Not sure if all 2.8's are going to be wrong, or if it's a year issue but will update as and when.

 

[aloria19]

OK - So finding boxes that are 20KM...... but not 20KM20. They look the same physically, they are mostly from different engine codes. Mine is 8140.47 but they are often from 8140.^^higher numbers. Plenty are 230 model donor vehicles but still not confident on pressing the "buy it now" button as not sure if the later two numbers after the KM pertain to ratios or driveshaft sizes. Please please please - anyone know anything about this?

 

[corcai]

Vin number

 

[goggs]

Try gearboxpartsonline.com for parts and kits. Gives a return so can note whether any good..

 

[aloria19]

Have PM'd you the VIN; Thanks for your interest

 

[aloria19]

Try gearboxpartsonline.com for parts and kits. Gives a return so can note whether any good..

Thanks for the reply

Can see a fair bit in their ebay shop for the 6 speed but not the earlier 5 speed.

I would need 3rd gear and 3rd/4th syncro assembly and rings....and once in there would probably sling a 5th kit in there as well as I know they can go at a moments notice.

It's all available from Coastal Motor homes but prices are eye watering.

The 20MK20 box is unfortunately one of the rarer ones so I am trying to broaden the search with cross compatible 20MK... boxes if there is such a thing. Trying to find the most economical way forwards.

 

[oigle]

Just a thought......an oil change for the box, using 10W/30 auto tranny fluid. can do wonders with failing synchros. Just don't use a synthetic version.
Haven't actually done it with a Fiat box but it works a treat with Mazda boxes.

Ian.

 

[aloria19]

Thanks for tip. As it happens, I replaced the oil at the weekend for
https://www.commaoil.com/passenger-vehicles/products/view/183

I did this as I had no clue what or how much was in there. There was a fair amount of sludgy thick tack in the bottom of the drain pan so glad I did it. 2.7ltrs came out and 2.7ltrs went back in of the above mineral based oil recommended for the vehicle by Comma's oil selector page.

Have only driven it a very short distance since (back to where I store it) and 3rd was certainly smoother going from 2nd>3rd but such a short distance have not yet tried 4th>3rd. Will report back with fuller findings but can't of done any harm!

 

[aloria19]

Ok - So I have now done about 15 miles in it. 2nd>3rd is now faultless. 4th>3rd is different but as bad as its ever been.

So I've bit the bullet and got another 20KM... box in this case a 20KM32. However it came off a vehicle with 16" wheels not 15" wheels.

When looking for spares for the internals of these boxes, there are no options for wheel sizes, so my best guess is that the only thing that will be different is the speedo worm. Can these be swapped .......anyone dabbled?

Donor vehicles was a 230 chassis cab (motorhome) and was a 2.5tdi the same as mine. Working the arms of the gearbox, all gears appear smooth to select (even on the deck with no oil in it) so I am hopeful.

Will keep you posted with final outcome, but in the meanwhile if anyone knows if the speedo worms can be interchanged (or even if you need to) I would love to hear from you.

 

[jontee61]

have you checked if you have the IVECO engine as the 2.5tdi was used by Fiat from 94---98 as that was the engine used. if you go to Wikipedia under Ducato good info on their.

 

[aloria19]

More broadly these are referred to as the Sofim engine. Some have no demarcation on the rocker cover, others say FIAT - the 2.5tdi (non common rail) Sofim is what it is, I thought???

 

[aww5490]

Just a thought......an oil change for the box, using 10W/30 auto tranny fluid. can do wonders with failing synchros. Just don't use a synthetic version.
Haven't actually done it with a Fiat box but it works a treat with Mazda boxes.

Ian.

I have earlier 1989 petrol ducato and used synthetic in g/box about 8 years ago. info on oil type was on TOC. talbot owners club site. Have had no problems after about 40k miles and g/box quiet.