Suspension and steering are two full sections of Ontario's inspection standard, and after brakes and rust they are the most common source of failures on older vehicles. They also contain some of the most specific numbers in the entire document.
Here is what gets measured.
Ride height: the 25 mm rule
The vehicle fails if one side is more than 25 mm higher or lower than the other, measured at the tire centreline.
The measurement is taken with the vehicle unloaded, parked on a flat level surface, with tires inflated to the specified pressure. It is a ground-to-vehicle measurement comparing left to right.
A vehicle sagging on one corner usually means a broken or collapsed spring, a failed strut, or — on an air suspension — a leaking air spring. It is also a common outcome of a lowering kit installed unevenly.
Suspension travel
The vehicle fails if there is no or very limited suspension travel due to a binding or seized suspension component, or due to improper spring stiffness or specification leaving the suspension topped or bottomed out.
This catches two things: worn-out components that have seized, and modified vehicles running springs that were never right for the car.
Springs
Coil springs fail if broken, shifted out of normal position, or if a spacer has been fitted between the coils.
Leaf springs fail if any leaf is broken, missing, cracked, shifted out of place, or worn more than 3 mm — either in the hanger contact area or where leaves contact each other. A leaf that has shifted and now contacts another vehicle part fails.
Torsion bars fail if broken, cracked, missing, or repaired by welding.
Composite springs fail if worn more than 3 mm in the load bearing area, broken, splintered, delaminating, or if a crack of any length is visible on both sides. The standard notes that some "fuzzing" or fraying in appearance is normal as a composite spring ages.
Shocks and struts
Tested by rapidly lowering and raising the vehicle and watching how it settles.
The vehicle fails if it oscillates more than two cycles after release. That is the specific test.
Struts and shocks also fail for being damaged, disconnected or missing, and for mounts and hardware that are broken, loose, binding or missing.
The road test backs this up: the vehicle fails if it bounces excessively, dives excessively under hard braking, or drifts on bumpy patches of road.
Ball joints, tie rods and linkage
Checked using tools and methods according to manufacturer service instructions, with the components appropriately loaded or unloaded.
Ball joints in an upper or lower control arm fail if:
- Insecure or loose in the knuckle or control arm
- Wear exceeds the limit shown by the wear indicator, the OEM standard limit, or the industry standard limit
- The joint has been injected with repair material — a shortcut that fails outright
- The retainer is improper, insecure or loose
Tie rods fail if bent, broken, cracked, or welded or repaired in a way that does not meet OEM standard.
Ball-and-socket joints — tie rod ends, idler arm, drag link — fail if bent, insecure, loose, or worn beyond the OEM or industry standard. They also fail for stripped or repaired threads, and for using a part that does not meet OEM standard.
Cotter pins and similar retaining devices fail if missing, or if a deficient part not meeting OEM standard has been used. It is a small item that fails vehicles regularly.
Adjusting sleeves fail if bent, loose, welded, or if the tightening bolt sits in a position that interferes with normal steering.
Steering free play: the published table
Where the manufacturer specifies a limit, that governs. Where it does not, the standard publishes a table based on steering wheel diameter:
| Steering wheel diameter | Free play must not exceed | |---|---| | Less than 350 mm | 45 mm | | 350 mm to under 400 mm | 50 mm | | 400 mm to under 450 mm | 55 mm | | 450 mm to under 500 mm | 60 mm | | 500 mm and larger | 70 mm |
A rack and pinion system also fails separately for excessive free play in the steering mechanism itself.
Steering operation
- The front wheels must turn from full right to full left and back without interference or roughness in the mechanism
- The number of rotations from centre to full left must equal the number from centre to full right, within half a turn
- The number of rotations from full left to full right must be at least 2
- The steering wheel fails if broken, damaged, loose on the spline, or of a diameter that is not OEM standard or equivalent
- Telescopic or tilt steering fails if movement exceeds the manufacturer specification, or where none is available, is greater than 6 mm — or if the column fails to lock into position
Tire clearance: 25 mm
The vehicle fails if the space between a tire and the frame, fender or any other vehicle part is less than 25 mm at any point in the turn, with the vehicle at rest.
Helpfully, the standard says not to reject a vehicle based on evidence of prior contact between the tire and vehicle parts — old rub marks alone are not a failure. But the road test then verifies clearance during actual operation: if contact occurs between a tire and any other part of the vehicle while driving over bumps and uneven pavement, that fails.
This is the rule that catches vehicles running wheels or tires that are too large, or that have been lowered without addressing clearance.
Power steering
- Fluid fails if below the indicated minimum level or contaminated
- Hoses and lines fail if cracked, worn by or in contact with moving parts, or if the distance to an exhaust component is less than 25 mm
- Pump and cylinder fail if inoperative, loose, insecurely mounted, or leaking at level 2 (drops that form but do not fall)
- Assist fails if power assistance is noticeably reduced, requiring more than normal effort to turn the wheels
What the road test adds
Section 11 evaluates steering behaviour on the road. The vehicle fails if:
- Steering pulls to the left or right while driven in a straight line
- Steering reacts excessively to a bump
- The steering wheel does not automatically return most of the way to centre while exiting a turn
That last one is a good example of why the road test exists. A binding strut bearing or a seizing upper mount can pass a static inspection and be obvious the moment you exit a corner.
Frequently asked questions
Will worn shocks fail an Ontario safety inspection? They fail if the vehicle oscillates more than two cycles after being rapidly lowered and released, if the shock is damaged, disconnected or missing, or if the mounts are broken, loose, binding or missing. The road test also fails a vehicle that bounces excessively, dives excessively under braking, or drifts over bumpy pavement.
Can a lowered or lifted vehicle pass a safety in Ontario? It can, but several rules catch modified vehicles: ride height more than 25 mm different side to side, suspension topped or bottomed out from improper spring specification, tire-to-body clearance under 25 mm at any point in a turn, and wheel spacers between the wheel and hub. Have modifications checked before booking.
How much steering play is allowed in Ontario? The manufacturer's specification where one exists. Otherwise the standard's table applies: 45 mm for a wheel under 350 mm diameter, rising to 70 mm for a wheel 500 mm or larger.
Do worn bushings fail a safety inspection? They fail when missing, loose, shifted out of place, or when wear or damage permits a suspension component, axle or wheel to shift out of position or required orientation. A slightly cracked bushing that still holds the component in place is a different matter from one that lets the geometry move.
Is a clunking noise over bumps an automatic fail? Not in itself — the failure has to trace back to a specific criterion. But a clunk usually means something is worn to the point that it will meet one: a ball joint beyond its wear limit, a broken sway bar link, a failed strut mount. Worth diagnosing before an inspection rather than during it.
Hearing something over bumps? We can check it against the standard before you book. Call (613) 789-2128 or see our suspension and steering service. Franco Garage, 70 Beech Street, Ottawa — a licensed Vehicle Inspection Centre.