PT 40, 42 & 43 owners. A ? about your tire size

[Gregory OConnor]

Kurt, proverbialy you always try and reinvent the wheel, now you
crossed the line. Stay with 12's.

steer tires on many commercial rigs are different than drive tires
(tag and power axle). I stick with the 12R's because the actual size
seem closer MFG to MFG and they are easier to find than metric (I
think Sears started metric just to sell 2 sets and an extra
drawer).

If you set up a rotation purchase of tires you can always have new
tires on the steer. I like to drop new upfront because I think slow
turning and stationary turning on hot asphalt can cause ply
adhersion/seperation issues. Regroovable tires always seem to be
built for the market that puts the tires to the test so I try and
find regroovables (but have never had them grooved). I always
feared that the comfort ride claims of Mitch' tire design have
compramised the build but that may just be a way for me to justify
not paying the extra 100 per the tire Mitch charge.

If you want my opinion, you have 8 good tires now. I would not add
more than 2 per the year. new upfront, the old front to one side of
the drive axle or the other side or split them up on the tags. This
would leave you with only the choice for 12's. no need to rotate the
tires around the back and height is not an issue from side to side
because the differential knows not to spin both sides the same.
Some think tire size overworks the diff ans screws with the ring
gear, I think it is worked by bad shocks or uneven roads. --- In
WanderlodgeForum@yahoogroups.com, "Kurt Horvath"
wrote:
>
> After a 2 hour web search I can not find anybody that makes a tire
in
> 315 75R 22.5.
> Everybody has a 315 80R 22.5 they are about 1" wider than a 12R
22.5
> & 11.3" Vs 12.5" in width, and the 315's are a little
shorter,19.6"
> Vs 19.8" loaded radius, overall diameter is the same @ 42.4", they
> both use 9" rims, the 315's have a 1700lbs single wheel higher
> capacity and a 1465lbs higher dual wheel capacity, per tire.
> The only thing I see as a problem may be the dual wheel spacing.
> 13.2" for the 12R and 14.1" for the 315's. The only other
difference
> is revolutions per mile, I'd say insignificant @ 2 RP Mile. Info
from
> B.F.Goodrich. The only chart I could find without bouncing all
over
> the web
> I've seen several size tires on comparable birds PT 40,42,& 43's,
> I've seen coaches with 11R 22.5, and the coach for sale on e-bay
> states it has 315's on it..
> Convention wisdom states all tires should be of the same size &
Mfg.
> I would like to have the heavier tires on the steer axles. I don't
> think 1/2 inch wider on each side of the tire in the front wheel
> wells would make a difference, though it is already a tight fit.,
and
> I'm not sure if the larger tires would have an adverse effect on
the
> overall drive ability. I'm hoping for better control , higher
> capacity and the added safety in a more capable tire.
> Any thoughts?
>
> Kurt Horvath
> 95 PT-42
> 10AC
>