California interstate speed limits

Reading the signs in Ca would lead me to believe if you have a tag axle then you are limited to 55.

Tom/Barb, Just because you have two rear axles doesn't limit your speed to the trailer speed.

The general answer to your question is you may travel the same speeds posted as a regular car, 55, 65, 70, whatever. The 55 is when you are pulling a trailer / object behind you.

AND, obviously safety conditions must be considered at all times.

Yes, speed limit in CA is common sense. Flow of traffic. 55 for trailers. If you get a cite even under the speed limit with huge letters across it RAIN , SNOW, or FOG you probably will be guilty.

Legally, you're considered the same as any vehicle, so whatever is posted. That is, CVC 22348 Maximum Speed. Towing is 55. That said, 22350 CVC says you may not exceed that speed which is reasonable and prudent, considering weather conditions, road and traffic conditions, so a LEO may determine 65/70 is too fast depending on the above conditions.

Question is, why would you want to?.....Dennis