Hi There,
If a 4y is fitted with diffs with ratio 5.10, uses 31 X 10.5 R15 tyres, will the fuel consumption be influenced when driving on tar at 120 km/h?
Thanks a lot,
Jaco
Diff ratio, tyre size and fuel consumption
- Jaco Versfeld
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Re: Diff ratio, tyre size and fuel consumption
Probably. I used to only get a shade over 5km/l when I had a Weber carb, get about 7km/l now since the EFI conversion. With the bigger tyres, the sppeedo speed is just about spot on too, according to the GPS. Diff ratio in mine is the standard Import diff, I think 4.875 <?> : 1.
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Re: Diff ratio, tyre size and fuel consumption
Jaco, Bigger tyres have many influences on your vehicle.
It changes the gearing of the vehicle, and on a 4y bigger means less power in the high gears, and you need to gear down more frequently to get up hills and stuff, which will have an impact on fuel consumption.
Rolling resistance is another thing that needs to be taken into account, as there is more rubber in contact with the road surface.
Wider tyres will also produce more wind resistance.
That said, the Hilux is not exactly the most aerodynamic vehicle on the road, and driving it at 120km/h will produce a heap of wind resistance and drag. Slowing down to 110km/h will reduce fuel consumption drastically and will negate the impact of larger tyres on your fuel consumption.
It changes the gearing of the vehicle, and on a 4y bigger means less power in the high gears, and you need to gear down more frequently to get up hills and stuff, which will have an impact on fuel consumption.
Rolling resistance is another thing that needs to be taken into account, as there is more rubber in contact with the road surface.
Wider tyres will also produce more wind resistance.
That said, the Hilux is not exactly the most aerodynamic vehicle on the road, and driving it at 120km/h will produce a heap of wind resistance and drag. Slowing down to 110km/h will reduce fuel consumption drastically and will negate the impact of larger tyres on your fuel consumption.
Thys de Jager
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email: thys@teamoffroad.co.za
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CEO and Refreshments Manager at Team Offroad.
2010 Hilux 3.0 D4D D/C 4x4 with GOMAD "Brood" Canopy. Tripod.
1997 Jeep Wrangler TJ 4.0 Sport. The original SFA. AGA... Gooi kole
email: thys@teamoffroad.co.za
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Re: Diff ratio, tyre size and fuel consumption
As ek baie gelukkig is kan ek 120km/h haal teen 'n helse afdraande. My gemiddelde spoed op die groot pad is maar 90-100km/h. 60-80km/h teen 'n opdraande. 4.875 & 31" bande
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1996 Ssanyong Musso 602EL - OME Suspension