[A/S] New Tires and Wheels

["Helen Countryman" <helncoun@xxxxxxx>]

We are looking for replacement wheels for an Airstream Trailer.  I'll 
give some background on the subject, then some discussion of our 
plans, then some questions.
Background
Our trailer is a 1964 Airsteam Overlander, a 26 foot model, riding on 
four tires and wheels.  Tires are 7.00X15.  The wheels are split rim.  
The last time we had a flat fixed we found it difficult to locate a 
mechanic that serviced split rim wheels.  The tires are over 25 years 
old, presumably due for replacement.  It appears to be time to get 
new wheels concurrent with the tires.  As the 7.00X15 is a high 
profile tire which is unavailable now, it appears appropriate to go to 
a 16" or 17" wheel to allow a tire size with the same diameter and 
similar width.
Tires on the trailer (set of four)
Dayton Thorobred Super EMT    nylon cord
8 ply rating (equivalent to Load Range D)
Spare (not originally with the trailer)
Goodyear Travel Trailer Hi-Miler    nylon cord
Load range C
These are bias ply tires.  Wheel for the spare is not split rim; 
checking it with a caliper shows rim width to be 6 inches.  Rough 
measurements on the split rim wheels indicates a rim width of 
either 6 or 6 ½ inches.
Wheels are six lug, 5 ½ inch bolt circle.  Gauge of material and 
construction give the appearance that they were designed for a load 
capacity of somewhere in the range of 2,000 to 2,500 pounds per 
wheel.  Wheels are black, with 'Baby Moon' hubcaps.
I found some old specifications for 7.00X15 radial ply tires.  
Presumably these approximately match the bias ply for load 
capacity and physical size.  The dimensions seem to match what I 
measure on my tires.
Overall Diameter                                                   29.4 to 29.7 
inches, depending on manufacturer and series.
Section width on 6.0 inch wide rim                    7.8 to 8.2 inches
Tread width                                          5.8 inches typical
Load capacity per tire
load range C                                                          1720 lbs
load range D                                                         2040 lbs
Of current (i. e., used on a significant selection of 2003 light trucks) 
light truck tires the one which appears to come closest for sidewall 
width and overall diameter is the 225/75R16.  Typical 
characteristics are:
Overall Diameter                                                   29.3 inches
Section width on 6.0 inch wide rim                    9.1 inches
Section width on 7.0 inch wide rim                    9.5 inches
Tread width                                                           6.4 inches
Load capacity per tire
load range C                                                          1966 lbs
load range D                                                         2335 lbs
These seem to have become a de facto standard for 'one ton' light 
trucks with dual rear wheels.  I expect that they would also be 
common on smaller motor homes with dual rear wheels.
The trailer wheel wells appear able to accommodate tires with 
sidewall widths up to approximately 10 inches maximum.
Plans
Pending response to this inquiry, I'm planning to get a set of four 16 
inch wheels with 7 inch wide rims and a set of four 225/75R16 tires 
for our trailer.  I've selected the 7 inch rim because it has a better 
offset for fitting the trailer's wheel well  -  in fact, the same offset 
as the current wheel.  I. e., track will be unchanged.  Wheel will be 
ordered black (powder finish), with baby moon hubcaps from the 
same supplier.
If this all works out well, I plan to write a technical article 
discussing this subject and including specific supplier names and 
part numbers, and offer it for publication to 'Vintage Advantage' and 
'Blue Beret'.
Questions
1.             Has anyone else done this type conversion?  If so please 
comment on results, wheel supplier, type, P/N, size, hubcap 
supplier, P/N, tire type and size, etc.
2.             Is anyone interested in having the old wheels and 
hubcaps?  (If so, you need to be available in South Everett, 
Washington to pick them up when I get them replaced.)
3.             For the technical historians out there  -  when we got the 
trailer the tires looked only a few years old.  Many years later they 
look much the same.  They've aged very well.  So:  in 1964, did 
Airstream use Dayton Thorobred Super EMT tires as original 
equipment on some of their trailers?  (Our trips have tended to be 
infrequent and usually moderately short.)

Lauren Countryman
23352
helncoun@gte.net