Heavy Duty tires & brakes vs "normal"
 

The heavy duty tires are 18.00x5.5 - it's a rare and expensive tire with a rare and expensive tube.

The normal tires are 6.00x6 8-ply - it's a more common tire, with a very common tube.

The 6.00x6 is a wider tire and runs at a lower pressure, so you have lower ground pressure.

Both tires are rated to carry the full gross weight of the aircraft.

Does anyone have any experience with both? Good, bad or otherwise? I thought I wanted to change to 6.00x6 so I have a more common tire/tube that's better suited to soft fields, but it turns out you have to change EVERYTHING that goes on the axle to change tire sizes - tires, wheels, hubcap$, brake rotors, brake calipers, brake pads, etc.

Thoughts?

If you keep the plane it's probably a wise choice to go with the more common size. Any certification issue with changing to that size? What model did you buy? I thought you bought a G model correct? Not sure they can go to the other size tire without a field approval. Which shouldn't be hard to convince with all the older Skymasters rolling on them

I have a T337E and it came with 18.00x5.5 "heavy duty" tires, wheels & brakes. There's no field approval needed with going to a 6.00x6; they're listed in my POH and in the parts manual as standard. 18.00x5.5 is listed as optional.

The main issue is that the HD wheels & brakes go with the oddball wheel size, so I have to replace much more than just the wheels & tires. I can't imagine I'll need HD brakes on backcountry strips. The weakest brakes will be able to lock the tires any time on grass & gravel. I imagine I'll save about 5-7 lbs/side.

The sticker price on the full 6.00x6 kit is about $2500/side; it'll obviously be cheaper if I scrounge & scrape the boneyards. I just need to make sure I get all the parts - almost everything that goes on or near the axle is different for the two sizes.

Yep, you are good to go with the original size of 6.00 x 6. Someone must have put the newer style on at some point for the HD brakes or it was a factory option. I would have to think there are some used or surplus parts out there that should save you some money