Technical Fiat Ducato Gear Ratio

[Dinoartois]

Hi,

I have a 2004 fiat ducato motorhome 2.8td.
I want to change the 5th gear to lower the rpm as it currently sits at quite high rpm around 2600 @ 60mph.
I am aware there are different options available but I am having difficulty finding the tooth number for the replacement cogs I am after? Does anyone know?

 

[bugsymike]

Hi,

I have a 2004 fiat ducato motorhome 2.8td.
I want to change the 5th gear to lower the rpm as it currently sits at quite high rpm around 2600 @ 60mph.
I am aware there are different options available but I am having difficulty finding the tooth number for the replacement cogs I am after? Does anyone know?

If still available I would suspect a gearbox from a minibus would be the answer.
By the way are you on 15 inch or 16 inch as that may be a cheaper option or even higher profile tyres.
Some years ago I had a Iveco Daily pick up with that 2.8 sofim engine and had been set in the ECU to 56 mph which made it a nightmare passing lorries, I used to have to wait for a dual carriageway with a right hand bend so I could creep past.
It came standard on 195x50x16 tyres from memory and I fitted 205x70x16 tyres and got around 65mph according to the GPS which helped.
This would obviously drop the engine revs at your normal cruising speed.

 

[Communicator]

Hi,

I have a 2004 fiat ducato motorhome 2.8td.
I want to change the 5th gear to lower the rpm as it currently sits at quite high rpm around 2600 @ 60mph.
I am aware there are different options available but I am having difficulty finding the tooth number for the replacement cogs I am after? Does anyone know?

A 2004 2.8TD Ducato will in fact be a 2.8jtd, with maximum torque at about 1800rpm.
The fifth gear was an addition to the original box, and heavier vehicles struggled with the large ratio gap between 4th and 5th. An alternative lower ratio was offered, and this is what you seem to have. It may be that your vehicle is best suited to the lower ratio, which will reduce stress on the clutch.

As may be inferred from the preceding paragraph, FIat only offered two choices, high, or low ratio. There is however a third intermediate ratio which was published on the Italian forum Camperonline. I was interested in this middle ratio alternative and purchased the parts for that alternative, but have yet to get round to installing them.

I will attach a translation of the original Camperonline post, and a pdf version of my own document detailing gears, ratios, road speeds, and engine rpm.

 

[Dinoartois]

If still available I would suspect a gearbox from a minibus would be the answer.
By the way are you on 15 inch or 16 inch as that may be a cheaper option or even higher profile tyres.
Some years ago I had a Iveco Daily pick up with that 2.8 sofim engine and had been set in the ECU to 56 mph which made it a nightmare passing lorries, I used to have to wait for a dual carriageway with a right hand bend so I could creep past.
It came standard on 195x50x16 tyres from memory and I fitted 205x70x16 tyres and got around 65mph according to the GPS which helped.
This would obviously drop the engine revs at your normal cruising speed.

 

[Dinoartois]

No, I dont need any of that... Just need to know the teeth numbers for the replacement cogs... thanks,anyway

 

[Torq]

You need to be more specific, these are gear sets for 5th gear. (X230)
31/53
STD 35/58
34/53
38/53
45/33
49/33
43/33

I'm running 38/53 in mine, it's about 20% lower than standard. It's not a 120kph on the motorway gear, I wouldn't bring it over 110 as it revs higher. But you can drop down to 50 to 60kph and then pull away without having to change down to 4th. It's the ideal gear for a big heavy tag axle camper.

The most common swap is 34/53 which is 6% lower than std. The ideal one, if you could find it is 49/33 at 11% lower.

 

[Dinoartois]

You need to be more specific, these are gear sets for 5th gear. (X230)
31/53
STD 35/58
34/53
38/53
45/33
49/33
43/33

I'm running 38/53 in mine, it's about 20% lower than standard. It's not a 120kph on the motorway gear, I wouldn't bring it over 110 as it revs higher. But you can drop down to 50 to 60kph and then pull away without having to change down to 4th. It's the ideal gear for a big heavy tag axle camper.

The most common swap is 34/53 which is 6% lower than std. The ideal one, if you could find it is 49/33 at 11% lower.

I can get the 49/33... Seems like a good option

 

[Dinoartois]

You need to be more specific, these are gear sets for 5th gear. (X230)
31/53
STD 35/58
34/53
38/53
45/33
49/33
43/33

I'm running 38/53 in mine, it's about 20% lower than standard. It's not a 120kph on the motorway gear, I wouldn't bring it over 110 as it revs higher. But you can drop down to 50 to 60kph and then pull away without having to change down to 4th. It's the ideal gear for a big heavy tag axle camper.

The most common swap is 34/53 which is 6% lower than std. The ideal one, if you could find it is 49/33 at 11% lower.

Many thanks for all the info I can get the 49/33 so will gove that a go.

 

[Communicator]

You need to be more specific, these are gear sets for 5th gear. (X230)
31/53
STD 35/58
34/53
38/53
45/33
49/33
43/33

I'm running 38/53 in mine, it's about 20% lower than standard. It's not a 120kph on the motorway gear, I wouldn't bring it over 110 as it revs higher. But you can drop down to 50 to 60kph and then pull away without having to change down to 4th. It's the ideal gear for a big heavy tag axle camper.

The most common swap is 34/53 which is 6% lower than std. The ideal one, if you could find it is 49/33 at 11% lower.

The OP's vehicle is most probably an x244, with MLGU box. I am rather dubious as to whether the full range of gear pairs are suitable for the MLGU box? As far as I know Fiat only offered two ratio options for the x244, with the camperonline suggestion making a third option,