Thank you all for your responses. I think I should be more specific,
so here goes:
I have a 2007 Toyota Tacoma, with NO optional anything. It's 2WD,
automatic transmission, and not very powerful. It has the smallest
engine, rated at something like 159 HP, but generally feels like less.
I think this may be because it has an automatic transmission.
I plan to do some driving up a dirt hill in about a month. It's not very
steep. I estimate the slope to not be more than about ten degrees
from horizontal. And there is not much growing there. I think it's
mostly bare dirt, with a few occasional smallish rocks. Unfortunately,
I don't know whether the ground is sandy, claylike, or what. It's not
in a valley, so I don't think it has a lot of sand. And I won't know until
I arrive how wet or damp it will be. The elevation is about 6,000 ft, and
this is in the Rocky Mountains.
Furthermore, I don't have much money. I recently bought a set of new
street tires (the original size -- 215/70 R15), and am concerned only with
spinning my tires while driving up this hill. I will be going very slowly, with
no load in the truck. Just me. So I would (tentatively) like to buy just 2
off-road tires and put them on the rear wheels. I have no idea how much
traction is available. I don't know whether it is 30% more, 50% more, or
100% more, or even more than that (all compared with street tires). So
I am looking for any suggestions based on real-life experience you have.
My concern is not with noise or durability of the tires. And I can certainly
be extra-careful while driving on pavement (I expect that the overall
handling of the vehicle would suffer on the street). I just don't want to
get stuck in the mud, several miles away from the paved road I used to
get to this hill.
I already plan to open the tailgate, in order to transfer a little weight onto
the rear tires. And I'm also thinking about using about 5 psi less air pressure
than I would if I were driving on a paved street. Of course, I would certainly
go easy on the throttle. And choose a route up this hill that has more gentle
slopes, so I can avoid any steep ones.
Any other ideas I should be aware of? By the way, I don't much know one brand
from another, when it comes to tires. And I am pretty poor. If you could share
your actual experience, I'd appreciate it. Looking at a comparison chart that uses
terms like "long tread life" or "best value" doesn't seem very helpful to me.
Now if someone said that I should definitely choose "mud tires", that would be
more meaningful. I have no idea how much a slightly "coarser" tread actually
grabs the ground, compared to a typical tread on a "street" tire.
Thank you in advance for your input.
Andrew Lampenfeld