Issues with oversized tires?

[AMG33D]

Hello everyone, I possess a Vito W447. I desire an update to 17-inch wheels with robust tires. The BFG A/T tires are excessively bulky for my requirements, so I am considering the Yokohama Geolandar tire. I have been informed that installing an oversized tyre could damage the automatic transmission due to increased strain. Does anyone here possess experience with this topic? Thank you.

[EatSuru]

Consult the handbook for the selection of available wheels and suggested tyres, and select one from that list.

Installing tires outside the specified dimensions may affect insurance coverage.

[badgx]

An automatic gearbox will remain unaffected; nevertheless, your speedometer will be inaccurate if the aspect ratio is not consistently maintained. Excessive alterations may lead to premature deterioration of your suspension and steering components.

[CyberNinja]

A larger (non-standard) rolling radius will undoubtedly impose some additional strain on the drivetrain during acceleration. This van may be transporting approximately one tonne of payload or pulling 2.5 tonnes.

However, the speedometer would undoubtedly provide an inaccurate reading, which would be inadvisable.

[CyberNinja]

Many van insurance providers are quite apprehensive regarding any non-standard practices.

[Darrellll]

I anticipate that the differential will fail before the automatic gearbox.
However, that would be contingent upon the extent of your demands.


Obtaining the torque specification for your box should be feasible. Subsequently, contrast the power output of motors directed towards it with that of your own.

[badgx]

The gearbox rotates the propeller, which drives the differential, which turns the axles, which in turn rotate the wheels.

Larger wheels may increase unsprung weight; yet, in the overall context of a one-ton van... What impact will they have?

[Darrellll]

My 639 has a curb weight of slightly under 2.2 tonnes.
The gross train weight exceeds 4.9 tonnes.
There is considerable tolerance required for the drivetrain to manage.


The percentage growth can be obtained from websites that display the percentage of increase in circumference. However, this is primarily attributable to the additional revolutions required to initiate movement, particularly on an incline, if so chosen.

Years ago, I upgraded the tyres on a Vito from 205/65 to 205/75 to enhance the ride quality. Over approximately 60,000 miles, it did not cause any damage. The speedometer was then as near to GPS accuracy as possible.

I would not appreciate the road noise and atmosphere, but to each their own.