Ram 2500 tire pressure

NebraskaNative wrote:
I can agree with BenK above except for the last line: "If not, then use the chalk or masking tape method to determine the proper PSI for 'that' loading during that test"

Bad advice, tire manufacturers have load tables for this exact reason. Using an arbitrary method to determine something as important as tire pressures is asking for trouble.

Thanks for the confirmation and say to the one point...said if not stock
or something like that...then must re-engineer for 'that' new, non-OEM
sized tire/wheel

How else would they figure out what the re-engineered tire/wheel's
PSI should be?

There was a 'try' at developing a system whereby the wheel center
down to pavement vs PSI, but that didn't fly. BFG was about the only
OEM that actually published spec's for their KO-AT series

How many folks actually go out and weigh their trucks in order to
use the OEM tables? Most won't and they come here asking HOW2 or "just
tell me a PSI and I'll use that"





Found this one posted by someelse on another forum and show the
typical 3 conditions of #1 under inflation, #2 over inflation and
#3 just right

Notice in #1, under inflation, it is holding up the weight and goes
to my comment that pressure has more to do with maintaining the shape
of the tire than just weight carry

These are on or with-in that tire's recommended rim width

Static and the dynamic will have the wheel roll over while the tire
side wall rolls over.




These images found showing the difference in cornering between the
old bias-ply vs then new radial, but is a good image to visualize
conceptually how tire will roll over during any change in direction


Bias-ply

Radial


Too low PSI will have the sidewall roll over even more






Sidewall bend-back. Image from Michelin's try in a new type of
bead, but saved it to show how lower pressure allows more sidewall
bend back, therefore more potential for roll over during a change
in direction.





This shows the PSI vectors working on the insides of a tire. They
are in all directions. Only 'ONE' is 'up', or holding up weight. The
others are maintaining the tire shape
http://img.photobucket.com/albums/v77/bentoy/Tire%20Wheel/Tirecarrysidewallpic.jpg~original



All this trying to answer the OP's question:

So my question:

Does anyone drop the rear tire pressure from 70 lbs when not towing, to the recommended 40 lbs, or some other pressure for a better ride? What has been your experience and your thoughts as Ram owners of this 'light load' concept?

Yes, but it won't handle as well and not all TV's will do well with
such a low PSI.

That the 40PSI is out of context...it depends on the vehicle in question,
tire size vs OEM, and how/where you drive

One neighbor has a CTD and drives like a little old lady. He does
drop his PSI, but when I've driven it...mushy and he did notice that
the out side tread ribs wore more than when he drove it

Nephew has a CTD and drives very much like me...his is aired up to
max sidewall *ALL* the time

Saying that it depends if the adviser drives just like you do, would
their advice then apply to you. Terrain and ambient too