Hi @savvy2011,
Thank you for your question and welcome to the Bunnings Workshop community, it is fantastic to have you with us.
How wide is the dip?
It doesn't look particularly wide, so you might get away with just putting a length of 190 x 35mm Outdoor Framing H3 Treated Pine along the dip and fixing it in place with some dynabolts. It's worth noting that direct contact between timber and concrete will increase the potential for rot, so you might want to back the timber with CAgroup 230mm x 10m x 500um Plascourse fixed in place with staples.
If the gap is too wide, you could use this same method and then attach some 1200 x 1198mm 12mm Plywood Pine Premium BC Grade to lessen the angle.
You might also be able to use a Matpro 900 x 200 x 25mm Outdoor Access Ramp Mat under each tyre to bridge the gap.
Let me know what you think.
Jacob
