Question for the wheels guys... You know those 15x6 6-lug artillery wheels that came on the original apache? They look like this: I think they came on NAPCO 4x4 conversions as well? In any case, does anyone know where I could find the original load rating of such a wheel?
I'd look at the Chevy restoration info available on their heritage site https://www.gmheritagecenter.com/ But you might not find what you want there, either. They appear to have load ratings for tires, but not wheels. Also I don't think that wheel has anything to do with the Chevy Apache truck, circa 1958....maybe something earlier? or aftermarket?
'37 - '45 3/4 ton wheels. The load rating must be higher than a standard Chevy wheel, but is that due to the wheel or the tire size/load rating? https://oldchevytrucks.com/blog/index.php/2010/02/artillery-wheels/ Wheel info is hard to find, so I'll throw this out there.
I did some searching and found that those are 38 to 45 15 inch 3/4 ton wheels. Artillery wheels weren't offered after 1945 according to Jim Carter but they are a popular replacement wheel. https://oldchevytrucks.com/blog/index.php/2010/02/artillery-wheels/
'35 - '42 Chev & GMC trucks, optional on 1/2 ton, standard equipment on "3/4 ton" Chev which was merely a long wheelbase 1/2 ton. Years ago, an old fella who hauled a heavily loaded 2 axle swap meet trailer thousands of miles a year told me he had destroyed dozens of standard & split rims from heat related explosions, and switched to these wheels with no problems since. They actually are 5 1/2'' wide, but sure look 6'' ...
I think that is in reference to the tire load capacity given the pressure. I hope it is anyhow! This is off topic, but I’m prolly gonna run a modern radial trailer tire.
I think it has more to do with the tires fitted, and specifically the inflation pressure needed. I had a neighbor who tried to 'upgrade' his 1/2T pickup into a 1T. Helper springs, heavy-duty shocks got him a long ways, but two items didn't work out. First was the tires/wheels. He managed to find some load range 'E' tires in a 15" size (I think they may have been equipment tires) and when inflated to their recommended pressure (80 psi?) started peeling the lip off the rims. I know he had at least two rim failures from this. The insurmountable issue was brakes... the first time he had it loaded up like a 1T, he went off the road at the first corner because it wouldn't slow down...
If the '40 Ford wheels fitted when you bought the trailer were original, then the Chevy wheels in question should be more than adequate when fitted with equally adequate tires. Further, IMO, using the latest technology trailer tires is wise....tradition is fine when up to the job at hand....not always the best option for maximum reliability and/or safety. In my twenty years of trailer tire experience, there are more poor quality trailer tires than good/great ones...buy the best you can find.