Okay, so the LTO has finally clarified that all modifications prejudicial to road and environmental safety, including rim sizes, is subject to Department Order 2010-32. We won’t waste our time posting a selfie video of ourselves doing an interview, but instead we just decided to bust up some myths which can probably help the LTO in coming up with some proper guidelines.

Is changing my car’s rim size going to make it less safe?

Hell, no. In fact, it’s already well documented that “plus sizing” (the act of increasing a wheel and tire size) the right way actually improves a car’s handling and sometimes even ride.

We have already discussed in detail way back in 2011, but as a refresher:

Plus Sizing supports the premise that it’s important to maintain the same overall tire diameter whenever changing tire and wheel sizes to ensure sufficient ground clearance, appropriate driveline gearing and accurate speedometer readings. Large changes in overall tire and wheel diameter can alter the accuracy of the speedometer as well as the effectiveness of several key safety components such as the anti-lock braking system (ABS), traction control and vehicle stability system.

In short, the LTO can and should allow the changing of rim sizes based on certain criteria (see the last item).

Will mud-terrain or all-terrain tires make my car less safe?

If safety is all that we’re talking about, then no. HT, AT, MT—these tires all work on asphalted roads provided that they’re in good condition and are properly installed (this is where tire balancing and alignment come into play).

That said, let’s look closer at these commonly found SUV or off-road centric tires. “HT” stands for “Highway Terrain.” These tires are made for paved roads and come as the OE or stock tire in most SUVs and pickup trucks. They’re quiet, comfortable, and long lasting.

Next, there’s “AT” or “All Terrain” tires. Thanks to their more aggressive tire pattern, they’re typically sought-after by SUV owners even if you want to keep your rim size stock (LTO, please take note—stock rims). These tires are designed to handle both on- and off-road driving. Some carmakers have even begun installing these as OE tires as well.

Finally, there’s “MT” or “Mud Terrain” tires. These tires do compromise a bit in terms of on-road quietness and comfort, but they can still be driven on paved roads. That said, extra caution is required to drive them at high speeds. They’re more susceptible to tire vibration and because their tread design doesn’t contain “sipes,” their wet weather braking and handling is a bit compromised.

Are steel bumpers road legal?

If we’re going to use the UN-ECE directive as stated in Department Order 2010-32, then no, they are not road legal. In the UN-ECE directive, it states:

• Headlamps and other front lamps should not have rigid projecting frames. If possible, they should be mounted slightly recessed in the bodywork.
• In an accident with a pedestrian, the area of initial contact with the legs of the person struck should be below and forward of the conventional bumper. It should extend over a vertical height sufficient to distribute the force over the legs, preferably below the knees of an adult person.
• External accessories (trimmings, spoilers, etc.) should be deformable, retractable so as to minimize the risk of injury.

That said, even safety conscious markets such as the US haven’t adopted a single standard for steel bumpers. Some states are okay with them, some aren’t. This has led steel bumper manufacturers to police themselves. For instance, they’ve designed bumpers that don’t cover any factory lighting (or at least provide provisions for proper lighting), and that they are of certain height, width, and design as not to be detrimental to pedestrian and cyclist safety.

What about LED spot lights and light bars?

We’re going to eyeroll you on this one. You can check out the full story here. It was shared by the LTO themselves so it passes their scrutiny.

Is it safe to raise or lower my car’s ride height?

Again, yes but under certain parameters. You cannot expect that raising or lowering your car’s ride height ad infinitum will not have any detrimental effects.

Considered as one of the most regulated markets in the world when it comes to aftermarket modifications, Australia has come up with a highly detailed suspension modifications manual. You can check out the New South Wales version of it here, but this is the sort of technical manual that the LTO should make. Here are some interesting bits:

• It distinguishes a “minor” and “major” modification. Minor ones don’t need a government re-certification while Major ones do.
• Examples of minor modifications: increase/decrease of ride height by 50 mm; change in wheel/tire combination of up to 7 percent of the largest size specified by the vehicle manufacturer.
• Major modifications require a reassessment and this includes: an increase in ride height between 50-125 mm, modifications that produce no change in ride height but involve conversion from coil to leaf springs, fabrication of suspension mounting points, fitting of a suspension of a different design.
• Naturally, there are some modifications that aren’t covered even by this 35-page manual, and to that end, the modifications require a government licensed certifier to make them road legal.