The hard part about I-5 is the speed limits for pulling a trailer.WA=60 mph,OR=55 mph, CA=55 mph AZ=65. Take I-90 to WA-17 to WA-395 to I-82 to I-84. You can go I-90 to I-82 to I-84 just a lot hills fro Ellensbug to Yakima.Take to Bliss ID-30 to ID-93 (ID-30 is a good road with 10ft lanes or you can take the exit Twin Falls exit.).Take ID-93 to NV-93 to I-15 .If you do not want to drive thru Las Vegas and have a Federal park pass you can go thru Lake Mead National Park. Fill up at the Loves truck at 93 & I-15 gas is real costly until you get the other side of Kingman AZ. After you get on I-15 the next exit is Las Vegas Blvd (604)take this exit. Stay in the Left Lane and turn left on Nellis Blvd (612). Stay in the left lane go to Lake Mead Blvd (147) turn left go to the park. Once in the park follow the signs to Hover Dam. You will get back on NV-93 a mile or two west of the dam turn left and go over the new bridge. You are now on AZ-93. going down the hill into Kingmam stay in the left lane get on I-40 east to AZ-93.There are two truck stops east of Kingman that have the best prices for fuel Loves the first is usual 4 cents less.On AZ-93 to AZ-60 to AZ-303 to I-10. You have two choices go through Phoenix or bypass.Take the east I-10 exit to go through Phoenix. To bypass take the west I-10 exit to AZ-85 to I-8 east .