Hanover, Germany – Continental has started making passenger car tires with the new “HL” load index code, indicating that they have a higher load-capacity than those built to the former XL standard.
On the sidewall, products with the new high load capacity display the HL code ahead of the size, as in ‘HL 245/40 R19 101Y XL’, according to the tire maker’s 21 Jan statement.
The company is currently producing the first tires to the new HL standard for OE fitments, but said they will also be available on the replacement market.
While large, powerful cars and SUVs with electric or hybrid drives are much heavier than conventional vehicles due to the addition of fuel cells, they offer little scope for fitting larger tires with higher load capacities, Continental explained.
At 825 kg (load index 101), the load capacity of the HL tire equates to a 10% increase over the XL standard of 750 kg (load index 98), the company stated.
Passenger car tires of this size built to the SL standard, adequate for many cars, up to and including mid-range models, can take a maximum load of 670 kg (load index 94).
“That makes the load capacity of the new HL tyres almost one quarter higher,” noted Continental, which expects growing demand from OEMs for tires with the new HL code.
Increasing the load capacity while at the same time meeting customer requirements required changes in both the tire structure and the rubber compound, said Dr. Stefan Habicht, who led the development project for these tires.
The trade-offs “needed to be resolved at a very high level,” Habicht explaining how his team reinforced the bead and enhanced the contour of the tire to reduce tire/road noise, and also optimised the pattern compound.
As a result, he said, “we were able to achieve low rolling resistance, ensure precision handling and keep mileage at its customary high level.”