Hi Mustang,
I have towed my c/c 685 up 3 times and a mates 6m Vindicator up once, let my tyres dow to 19 PSI up to Indian and then down to 16 for the rest of the trip, never has any tyre issues. Same pressure both car & Trailer,
I had the most trouble with the Vindicator as the trailor was a real sand Plough, Th C/C trailer has straight axels and the chassis sits a lot higher with less bits hanging down getting caught in the soft sand. Have been through Indian at its best (no additional vehicles required) and at it worst taken 4 hours to get 4 boats through.
Hopefully you get a day or 2 of rain a couple of days befor you head up. You are always better to hook another Tow vehicle or 2 on for safety, vrs getting stuck as you can loose hours, and break a lot of gear extracting a boat and car. We used 3 additional vechiles on year and need every bit of it.
I was aprehensive the first time, but you are headed in the right direction with additional vehicles, It can be a challange, but their is no better feeling than pulling you boat out of the water at Waddy, having a beer after a great days fishing, Enjoy your Trip
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