Re: [a/s] Stuck wheel lug nuts on Aluminum wheels!

[Susi and John Burchard <saluqi@xxxxxxxxxxxxx>]

The problem I've had with the "pros" (or at least the tire shops) is that they
often have some kid doing the actual mounting of the wheels on the vehicle (the
"old pro" having done the balancing, and maybe installing the tire on the rim). 
The kid is armed with a BIG air impact wrench and typically cranks the nuts down
so tight I can't get them off with my own not too puny electric impact wrench. 
I have bent a big breaker bar trying to budge such a nut.  Nothing to do but go
into the next tire shop and get the kid to remove the nuts with his BIG air
impact wrench, and then you put them back on yourself.  I can't think this is
good for the studs.

I put penetrating oil on the studs and it does make it MUCH easier to remove the
nuts the next time.  These are 9/16ths studs with 1 inch nuts and steel rather
than aluminum rims, on a 28 foot Class A motorhome (Argosy) on a GM P30
chassis.  The torque values for those are 120 and 140 foot pounds (single and
dual).  I think the air gun guys must be putting them on with 300 or more,
frightening to contemplate.  Also no fun to be stuck by the side of the road
somewhere with a flat tire and no possibility of removing the wheel to change
it.  No option but to arrange to be towed into the nearest tire shop.  Grrr.

On another note, I did crawl underneath and measure the space behind the rear
axle.  The width between the chassis frame rails is about three inches less than
the diameter of the spare wheel ... actually it would fit, snugly, between the
rails if I could slide it into the channels from in front; but a) there is no
room to do that because the open end of the channels is too close to the rear
diff housing, and b) the depth of the channel top to bottom is at least an inch
less than the width of the tire tread.  So forget that option.  There's not
enough ground clearance to mount the spare below the rails.

I also weighed a tire and rim, and guess what, I seriously underestimated the
weight.  The rim with tire mounted weighs about 95 pounds.

On yet another note, I tried today to get a load/inflation table for the tires I
am using (Cooper C120 8R19.5 all steel radials).  Having struck out some time
ago on the Cooper web site, I tried the large tire shop from whom I bought the
tires.  No luck at all.  Their approach was just inflate to the listed max
pressure (110 psi single, 100 psi dual).  That's probably not even safe, because
the rims are probably not rated for that pressure.  I have no way of checking
that till the next time I have to replace a tire.  I suspect, but do not know,
that those rims are rated for 85 psi maximum pressure.  After a while I managed
to get the manager to understand what a load/inflation table is.  They didn't
have one.  They also sell Michelin tires.  Don't have a table for those either
(and I struck out on the Michelin web site too).  So the theory is nice, but the
practice @$*?#.

There is a table of sorts in the Bob Livingston RV maintenance book.  It is for
LR D tires.  Mine are LR F.  I think the vehicle originally came with LR D tires
but in several years of prowling the tire shops I have yet to find one which
could sell me a LR D tire in 8R19.5 size.  I have never seen anything but LR F
in that size.  There are some hints in the Livingston table that the
load/inflation values are the same for tires of different load ranges.  But I am
concerned there might be a different minimum pressure for the LR F tires with,
presumably, stiffer sidewalls.  Does anyone know?

I am going NOMAIL this evening because I will be out of town for the next two
weeks.  So if you have some information for me on this one, I would appreciate a
copy by private E-mail to saluqi@ix.netcom.com.  Thanks!

John

Susi and John Burchard
saluqi@ix.netcom.com