Compared　with　passenger　cars,　heavy　vehicles　have　larger　loads,　longer　bodies,　more　steering　modes,　and　are　more　likely　to　cause　improper　steering　angle　relationships　among　the　wheels,　resulting　in　uncoordinated　steering.　This　uncoordinated　steering　makes　the　tyres　roll　and　drag,　which　results　in　abnormal　lateral　and　longitudinal　slips,　changing　the　lateral　and　longitudinal　mechanical　characteristics　of　tyres　and　leading　to　low　path　tracking　accuracy　and　poor　steering　performance　of　vehicles.　Therefore,　a　tyre　model　containing　lateral　and　longitudinal　mechanical　characteristics　under　heavy　load　is　the　key　to　solving　the　problem　of　uncoordinated　steering　in　heavy　vehicles.　Firstly,　with　the　physical　tyre　model,　the　lateral　and　longitudinal　slip　is　described　as　carcass　deflections.　With　the　carcass　deflections　and　contact　pressure　distribution　of　heavy　load,　the　tyre　forces　under　uncoordinated　steering　conditions　are　derived.　Then,　the　tyre　imprint　parameters　are　obtained　with　a　test　bench,　and　a　two-dimensional　contact　pressure　distribution　model　is　established　to　reproduce　the　contact　pressure　distribution　of　tyre　under　heavy　loads　and　dynamic　slips.　The　comparison　results　with　Magic　Formula　(MF)　and　Trucksim　are　generally　consistent,　proving　the　effectiveness　of　the　model.　Finally,　a　lateral　and　longitudinal　tyre　force　distribution　control　of　vehicles　is　carried　out　based　on　the　established　model.　The　results　of　the　Trucksim-Simulink　co-simulation　show　that　the　path　tracking　accuracy　of　vehicles　is　significantly　improved,　which　demonstrates　that　the　tyre　model　incorporating　lateral　and　longitudinal　mechanical　characteristics　under　heavy　loads　can　provide　a　theoretical　basis　for　solving　the　problem　of　uncoordinated　steering　in　heavy　vehicles.