I called in at a local motor factors to price up some diff oil for my transit I know it should be high performance oil they quoted £25 per litre so I rang my local Ford dealer they took the reg and came back with a price of £11 per litre when I asked it it was 75/140 high performance oil they said it's 75/140 but not high performance, that's the oil their system recommends for my transit.
Can someone tell me which one I need please

