Pay us the same as Clarkson – or we quit!

Between them, they have shrugged off criticism for ramming a 300-year-old chestnut tree, sipping gin and tonics at the wheel of a car and dashing to the North Pole in a gas-guzzling 4x4.

But it seems the testosterone-fuelled harmony of Britain's leading trio of petrolheads is in danger of disintegrating over the delicate matter of who is paid what to present Top Gear.

While Jeremy Clarkson, the denim-clad high priest of the nation's unreconstructed middle-aged males, makes a reputed £1m a year to host the BBC's hugely popular – and lucrative – motoring programme, his co-presenters, Richard Hammond and James May, have long been relegated to a lower pay bracket of about £15,000 per show.

But after Hammond, 38, recently raised his profile via the unorthodox method of crashing a jet-powered dragster at more than 200mph and May, 45, branched out into the world of wine with a BBC2 series alongside oenophile Oz Clarke, there are now fears that they may be about to leave Top Gear by refusing to sign new contracts.

Negotiations between the presenters and BBC managers are understood to have ground to a halt after they insisted their irreverent brand of weekly worship of the combustion engine deserved similar financial reward to that of Clarkson, 48, whose stream of books, DVDs and newspaper columns earned him £1.7m last year.

Agents for both men are believed to have argued that they have emerged from the leather blouson-shaped shadow of Clarkson because of the response to Hammond's near-fatal crash in 2006 and May's success in Oz and James' Big Wine Adventure. BBC managers say Top Gear remains their main "shop window" and they should be paid less than their high-profile co-host.

The current six-programme series of Top Gear, which regularly attracts more than eight million viewers, is to end this summer and, although the team are contracted for a 12th series in the autumn, all plans for subsequent runs of the cult show have been put on hold.

A source close to the negotiations said: "Richard and James are adamant that they will no longer be second rankers to Jeremy on this. They feel they all have similar profiles now and should be receiving similar fees. It is possible one of them, or both, might feel compelled to leave."

A BBC spokeswoman said: "We never comment on specific contract negotiations."

Since its arrival in its current format in 1995, Top Gear has become one of the BBC's most loved and profitable franchises, with multiple spin-offs including a magazine and a road show.

Despite falling foul of critics and regulators for some of their more irresponsible stunts, the adventures of Stig, the enigmatic test driver, and the programme's excoriating reviews of some mass-production hatchbacks are screened in 28 countries from Denmark to Ukraine and have a global audience of more than 200 million. Deals have recently been signed for the US and Australia to make their own versions. Last month, Clarkson signed a new deal with BBC Worldwide, the corporation's commercial arm, which is thought to give him a share of the profits made from Top Gear's international sales.

The programme's success is based on a mixture of outlandish stunts, including playing ice hockey with Suzuki jeeps, and an unapologetic pursuit of a speed-freak agenda.

The trio have frequently fallen foul of critics and regulators. A race across the Arctic Circle in a pick-up truck was branded "highly irresponsible" by Greenpeace and the BBC was forced to pay £250 to residents of a Somerset village after it emerged that damage to ancient horse chestnut tree was caused during filming of a "strength test" for a 4x4 vehicle.