ok fellas,


1997 F150 which i went from 255/70r16 to 295/75r16...very big jump. The issue that i have developed is that the bed (particularly the tail) seems to bounce pretty good. Anyone have any ideas? I had turned the torsion bars to level but the ride definitely suffered so I took it back down. Ideas as to how to eliminate the bounce?

Also... i seem to be tremendously underpowered. Anyone find this with the 4.6? 160K miles... had new plugs, coil packs and wires, etc... just seems weak.... am looking to buy a boat and not sure this would pull it...

the bigger tires may have something to do with the under power issue, but figured I would ask...

Nice RIGS!!!!!!! thanks..... Earl

 

You went from Passenger rated tires to E rated tires (capable of satisfying a 1 ton truck's capacity) the stiffer heavier (lots heavier) tires are Going to ride like chit in comparison. And it most definitely is why you're feeling underpowered. You're pushing at least 50 more pounds of rotational weight per corner, as well as giving you the effect of having taller gears due to the larger diameter of the new tires (same effect as towing a trailer 24/7)

 

What psi you have the tires at? They are a lot bigger which will kill your power, especially with a 4.6.

 

Are the tires cupped? I'm running 35x12.5R17's and no bounce.

Did you get an alignment after messing with the T-bars? That would have to do with the front, but you still need to do it. Who knows, may solve your issue too lol.

I have the 4.6 on stock gears with my 35's, and yeah, not a lot of power lol. I didn't have a big issue when I went from 245's to 285's though, still seemed normal. What tire do you have now? I had 35x12.5R17 good year fierce attitudes and those where a lot lighter than my current Toyo A/T's. I could feel the second I got past 30 that the truck could tell the difference lol.

 

I don't know if it would be quite 50 lol. I see maybe 20.

 

Obviously you have had a true Load E rated tire. I have run 295/75R16 and they were 35lbs heaver a piece than a Load D 35x12.50 Toyo.

 

I dont think they are cupped as I watch the air pressure pretty regularly on all my stuff (had a front tire go bad on my motorcycle during a 10 day trip and that made me much more aware-- i.d. expensive slap up side the head, lol)... and i didnt mess with the t bars due to the headache of trying to get one out so put them back at stock. thanks for the info... the tires i have now are 295/75R16...fill the fender wells just about right but might go to 285's when i replace these.

 

270.... i run them at the recommended pressure on the tire... admittedly too sleepy to recall the number but I check it pretty regularly...