A friend of mine was telling me that driving East on I-40 into Flagstaff is a long and steep drive. That I will be down to 35 mph at times. I was also told the same about Grants Pass in I-5 going into...
Grants Pass I found the winding road more of an issue than the grade! We just ran the 40 from Barstow to OKC a couple years back no problem with 36' gasser in signature.