Blew a steer tire, new tire questions.

[Mr.green]

Yowsers! Had the family packed in the crew cab dually on the way to the in-laws today when the truck started having a weird vibration, slowed down to 45 and bang! Drivers side steer tire blew and we headed into on coming traffic. Man handled back into my lane an off the state highway into the ditch. Blew the side wall, peeled the tread off and pulled the back part of the inner fender well up an into the remains of the tire.

I was able to beat the fender well back with a 3lb sledge and put the 36 year old spare on, after digging down for clearance and limped her home.

I will be replacing both steer tires now. Here is my question.

The SPID calls for a ZPF and XPF 7.5x16/D tube highw. The rims are original firestones.

Seems all 6 tires have tubes in them.

What size is a 7.5x16 and are the tubes still needed?

Still got a few skid marks in my shorts to clean up.