Ducato wheel question

sludgesurfer

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Please someone help me out here.

I have a 2018 Autotrail on a 2018 plate Ducato. 2.3 multi jet 2.

I'm wanting to go from 15" to 16" wheels and I'm trying to find out if my 'version' can accept 16" wheels. The manual has 6 different versions listed:
Light 15", light (tempo libero) 15", light 16", light (tempo libero) 16", Maxi and Maxi Tempo Libero.

Unless I'm missing something, there's nothing on the VIN plate which tells me which of these models I have.

Any assistance much appreciated.
 
Your speedo will be out, so either a satalite speedo or a g box removal and new speedo drive gear if available 0of which i dont think is out there.
 
I'm aware of the potential implications on speedo and gearing.

Many have done this change without issue. My speed is currently under reading against GPS which makes me think I should have been on 16s or that the van is designed to accept 15s or 16s. To establish this I need to know the version type, hence my question.
 
sludgesurfer said:
I'm aware of the potential implications on speedo and gearing.

Many have done this change without issue. My speed is currently under reading against GPS which makes me think I should have been on 16s or that the van is designed to accept 15s or 16s. To establish this I need to know the version type, hence my question.
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Something i had to do as mine was miles out, sat speedo works well.
 
I wish people wouldn't make a blanket statement of "your speedo will be out" if you change wheels. See it here all the time and it is total BS.

The speedo reading is determined by the rolling circumference, NOT just the wheel size. The rolling circumference is a combination of Wheel+Tyre.
If the tyres chosen to go with the bigger wheels are the appropriate profile, the rolling resistance is not affected. End of.
 
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Wikdebus, Totally agree on the rolling circumference. In my case the purpose is to increase ground clearance and I'll be fitting the similar tyres so speedo and gearing will be affected.

Colinm, whilst I suspect you're right, it's not something I want to leave up to suspicion. They weren't fitted with Fiat branded alloys from new which I always found suspicious. There must be a way of identifying from the VIN surely?
 
I originally had 225 x70 x15in if you want to keep the same rolling circumference you have to use 225 x 65 x 16in that will keep them the same .The problem for me was I wanted to put BF Goodrich all terrain tyres on but you can't get them in 65 size only 225 x75 x16in so yes my speed is out .it is spot on at 30mph but it reads 4mph slow at 70 Ive ran this since 2014 and it hasn't bother me one iota.the good thing about it is you can cruise at the same speed as before with less revs.
 
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wildebus said:
I wish people wouldn't make a blanket statement of "your speedo will be out" if you change wheels. See it here all the time and it is total BS.

The speedo reading is determined by the rolling circumference, NOT just the wheel size. The rolling circumference is a combination of Wheel+Tyre.
If the tyres chosen to go with the bigger wheels are the appropriate profile, the rolling resistance is not affected. End of.
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I think the OP is looking to fit tyres the his bigger rims. Not rubber bands. That said fitting sensible tyres would probably correct the speedo reading.😬
 
Trotter said:
I think the OP is looking to fit tyres the his bigger rims. Not rubber bands. That said fitting sensible tyres would probably correct the speedo reading.😬
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when you go up one inch on a wheel, you drop about 10 on the aspect ratio. it is not a massive difference. You should check the facts first.
 
Thanks. All good info.
The max axle weights are 1,850kg and 2,000 kg. I can't find a Fiat resource which confirms which chassis type this corresponds to. Can anyone direct me to one?
 
sludgesurfer said:
Wildebus, Totally agree on the rolling circumference. In my case the purpose is to increase ground clearance and I'll be fitting the similar tyres so speedo and gearing will be affected.
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A perfectly valid thing to do and in that case the speedo and gearing WILL be affected as you know.
In both my VW T4 and VW LT, I fitted 'oversized' tyres deliberately as both vans gearing was too high for distance travelling. Made a useful difference. My T4 went from an approx 7% overread to spot on. The LT speed ended up slightly underreading which was a bit of a pain but I could use the Sat Nav speed to be sure what the real speed was.

Long as the PCD and centre bore is the same, you can go 15" to 16". There can be a problem with some vehicles going DOWN in size if the vehicle has larger brake discs and calipers but bigger should be fine.

sludgesurfer said:
Colinm, whilst I suspect you're right, it's not something I want to leave up to suspicion. They weren't fitted with Fiat branded alloys from new which I always found suspicious. There must be a way of identifying from the VIN surely?
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I don't think that many vans had Alloys as standard? My Autotrail was fitted with standard Steel Wheels when I bought it and I added aftermarket Alloys.
Not sure if you have Steels still or alloys, but word to note .. If your hubs are the same as my Ducato hubs (mine is an X250, you have an X280(?)), there is a little protrusion on the hubs that has to be removed when fitting alloys. Think it is a bolt that is undone but might need cutting off? just something that could throw some tyre dealers if they are not aware?
 
sludgesurfer said:
Thanks. All good info.
The max axle weights are 1,850kg and 2,000 kg. I can't find a Fiat resource which confirms which chassis type this corresponds to. Can anyone direct me to one?
Click to expand...
You need to measure the PCD to be sure, then the new rims WILL FIT.
 
I found talking by phone to these guys very helpful in a similar situation. Plus as a cross check you can enter your reg on their website to get appropriate wheels. I eventually bought mine from them too.
 
Not sure if you have Steels still or alloys, but word to note .. If your hubs are the same as my Ducato hubs (mine is an X250, you have an X280(?)), there is a little protrusion on the hubs that has to be removed when fitting alloys. Think it is a bolt that is undone but might need cutting off? just something that could throw some tyre dealers if they are not aware?

Yes Wildebus, I had this issue with the locating lugs. Only spotted by eagle eyed local fitter who wasn't 100% satisfied with the way the alloys were seating. Another fitter might have just done the bolts up tight and left it at that. The lugs which prevent the alloys seating properly just unscrew. No need to cut them off.
 
sludgesurfer said:
I'm wanting to go from 15" to 16" wheels
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sludgesurfer said:
My speed is currently under reading against GPS
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With the current set up when you travel for an hour at an indicated 30mph the wheel will rotate “n” times and the vehicle will travel “n” multiplied by circumference of the tyre inches. If the speedo is under reading the distance traveled will be greater than 30 miles.

If you do the same journey, but with a larger diameter tyre, the wheel will turn the same number of times but each rotation will take the vehicle further.
i.e the distance travelled will increase and thus the under reading will also increase.
 
wildebus said:
I wish people wouldn't make a blanket statement of "your speedo will be out" if you change wheels. See it here all the time and it is total BS.

The speedo reading is determined by the rolling circumference, NOT just the wheel size. The rolling circumference is a combination of Wheel+Tyre.
If the tyres chosen to go with the bigger wheels are the appropriate profile, the rolling resistance is not affected. End of.
Click to expand...
10 points as correct, but whats the point of fitting bigger wheels and low profile, more damaged rims with potholes along with a harder ride, and no gain in fuel as ratio the same. :unsure:
 
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