these trucks can take it
what the auto transmission cannot take is HEAT
when you add some stress like big tires without re-gearing it does indeed effect your drivetrain, but these Ford drivetrains are stout enough to handle 33's without massive upgrades (like lets say you put 33's on a Jeep cherokee lol your gonna break stuff ) BUT you do need to be aware of a few things
changing your gear ratios when you go to a larger tire (longer rolling diameter) will bring the engine and transmission back into the stock powerband for optimum performance and MPG (computer tunes aside for now)
The additional stress of larger tires of course does wear heavy on the brakes, CV axles, ball joints, TIE RODS, U joints, etc... but the most expensive fix is the auto transmission. Typically on our trucks the axleshafts brakes, etc can handle teh larger tires but off road you want to be more careful not to spin tires. Breakage occurs when a tire is spinning (like in the air) and then comes down and gains traction (like on a rock)
KEEP YOUR AUTO TRANS COOL
upgrade to a LARGER aux trans cooler and get a trans temp gage
HEAT removes the transmission fluids ability to cool and lubricate
without cooling and lubrication its metal on metal and heat failure
Keeping these V6 transmissions UNDER 200 degrees in the pan their entire lifespan (even under the hardest conditions) frequent fluid and filter changes will make them last the way they were designed to, 160-200K miles typically
your 98 can handle 33's in the drivetrain
yes it requires more frequent maintenence, shocks, brakes, everything wears faster..but it wont snap off like a twig cough cough jeep dana 30 cough cough
