Hi everyone. There are many technical arguments and points of view about the merits of LT or ST rated
tires for trailers. It's not the intention of this post to retread that debate (if you'll pardon the pun) as it is well documented elsewhere.
What I want to tackle head on is what can politely be called "misinformation" being spread by multiple chains of tire retailers here in the Okanagan Valley of BC. This post is relevant to RV trailer owners purchasing
tires here in BC. Earlier this year, I went shopping for new
tires ...
I was told by two different chains of tire stores in Vernon, BC that it was illegal in BC to supply or fit LT rated tires to trailers. I called a different chain store in Kelowna and got the same answer.
Curious - as it is legal in quite a few jurisdictions on both sides of the border - I looked up the relevant BC law and searched the text for references to ST or LT. Nothing. Then I read the whole act - it's surprisingly brief - and there is nothing about tire ratings whatsoever. Tire condition yes, not mixing radial and bias ply yes, and so on, but nothing about tire design.
I contacted the CVSE (the guys who enforce commercial vehicle safety in BC) and received the following email, edited for brevity:
<<< Hello xxxx,
I have had a chance to review your question about laws in BC regarding trailer tires.
Specifically, the regulations relating to tires is based on the condition and bias ply or radial type. However, this does not state that a trailer must be equipped with trailer tires. I have provided the applicable regulations below for your reference.
Defects in pneumatic tires
7.161 (1) No person shall drive or operate a motor vehicle or trailer equipped with pneumatic tires that are not in good order or that have any one of the following defects or conditions:
(a) cord break or an air leak;
(b) tread damage including cracks, cuts or snags in excess of 2.5 cm in any direction and deep enough to expose the ply cords;
(c) bumps, bulges or lumps apparently caused by separation of the tread or sidewall from the ply cords or by partial failure of the tire structure, including the bead area;
(d) tread worn to the extent that
(i) in the case of a commercial vehicle with a gross vehicle
weight rating of 5 500 kg or more, less than 3 mm of tread groove depth of a front tire or 1.5 mm of tread groove depth of a rear tire, or
(ii) in the case of a vehicle other than a vehicle referred to in subparagraph (i), less than 1.5 mm of tread groove depth on any tire
remains at 2 points on the circumference of the tire tread not closer together than 38 cm, or tread worn to the extent that tread wear indicators in any 2 adjacent grooves of the tread contact the road surface.
(2) No person shall drive or operate a motor vehicle or trailer that is equipped with both bias ply tires and radial ply tires; unless the vehicle operates on more than 4 wheels, in which case bias ply tires and radial ply tires shall not be used on the same
axle.
(2.1) Notwithstanding subsection (2), a person may, during the period a regular tire is unusable due to its having been damaged, use a limited mileage temporary spare tire specified by the vehicle manufacturer for use with the other tires on the vehicle provided he makes arrangements forthwith to repair or replace the tire for which the spare tire has been temporarily substituted.
(3) No person shall drive or operate a motor vehicle or trailer equipped with a tire that has been regrooved or recut, except a special tire that has extra undertread rubber for this purpose and is identified with the word "regroovable" moulded in the tire by the manufacturer.
(4) No person shall drive or operate a motor vehicle or trailer, except an implement of husbandry or a slow moving vehicle as defined in section 7B.01, that is equipped with a pneumatic tire not designed and manufactured for highway use and that does not have a tread pattern of material across the area of the tire in contact with the highway.
(5) No person shall, without an overload permit issued under the Commercial Transport Regulations, B.C. Reg. 30/78, drive or operate on a highway a vehicle so loaded that the tires are loaded above the maximum load specified by the tire manufacturer for the tire size, ply rating and service speed.
[en. B.C. Reg. 153/71, s. 3; am. B.C. Regs. 205/72, s. 9; 343/77; 452/82, s. 1; 206/96, s. 2.]
Tires, wheels
20 A vehicle shall be equipped with tires in compliance with sections 7.16 and 7.161 of the regulations.
No tire on a vehicle shall have any of the following defects:
(1) Cord break or air leak;
(2) Tread damage including cracks, cuts or snags in excess of 25 mm in any direction and deep enough to expose the ply cords;
(3) Sidewall cracks, scuffs, cuts or snags to the extent that body cords are damaged or exposed;
(4) Bumps, bulges or lumps apparently caused by separation of the tread or sidewall from the ply cords or by partial failure of the tire structure, including the bead area.
The wheels and tires with which a vehicle is equipped shall be of the same size on one
axle.
No wheel shall have loose, missing or defective bolts, nuts or lugs, or bent, loose, cracked or defective rim or wheel flanges.
A wheel shall not have any missing, loose or broken spokes.
Hub caps shall be of such design and construction that minimizes the damage done to an object or injury to a person coming in contact with it.
The tires of a vehicle presented for inspection between May 1 and September 30 shall not be equipped with studs, and during the remainder of the year vehicles equipped with studded tires shall comply with section 19.03 of the regulations.
A disk wheel shall not have elongated bolt holes or cracks between handholds or stud holes.
A cast wheel of spoke type shall not be cracked.
Each rim and ring shall be matched and no rim or ring shall be bent, sprung or cracked.
A wheel or rim shall not be repaired by welding unless the weld repair is to an aluminum wheel or rim and is made in accordance with the Weld Repair of Aluminum Alloy Wheels Regulation.>>>
CONCLUSIONS: I suspect bad training and incorrect procedure manuals at the tire retailers. Probably some ST trailer tire manufacturer promoted this idea because it was the case in their home state or province, and never checked to see if it applied elsewhere. Regardless, if you live in BC, it ain't true!