3 year old sleep issues

We have a 3 year old at day care 4 days a week. She dropped her nap around the start of the year.
She wakes up around 5:30 or 6am nearly every day. I drop her at day care at 8 and pick her up around 5pm.
She goes home in a trailer on the back of my bike, and this is where the trouble starts. The trip is about 25 minutes, and she usually falls asleep, anywhere from 10 go 15 minutes into the trip.
This translates into 7:30 bed time turning into up to 2 hours of tantrums and negotiation. Tonight she was in bed by 7 and finally asleep by 9!

Any advice is appreciated.
Cbeers

Does she rest at child care, even if she doesn't sleep?
Could you try and give her a little snack/treat on way home to keep her awake? Or a special toy she doesn't get to play with often?

25 mins is a long time to stay awake if you've been on the go all day at childcare though... could you stop after 10 minutes and give her a treat/toy?!

we found that a nap at daycare at lunchtime was much better than a nap at 5pm on the way home.