Depending where you are headed for in Scarborough then the following may be a suitable alternative. We regularly visit The Camping Club Site which is to the north of Scarborough .
The route we use is A19, A174 (locally known as the Parkway). Exit at Marton in Middlesbrough, head towards Gusborough and then on towards Whitby. At Whitby head for Scarborough.
I prefer this route to the A170 and the caravan route - it can be a nightmare in the village of Ampleforth - I have been stuck due to parked cars! If going to south Scarborough I find it less stressful to stay on the A19 and then use the A64 even with the added mileage from the North.
Regards Nigel