265 to 285 - Power Loss?
 

I have an 03 FX4 w/ the 5.4L engine...I am wanting to go from the stock tire size 265/70/17 to the BFG All-Terrain 285/70/17.

My only concerns are power loss and gas consumption. Could anyone that has upgraded to this size give their input??

How much off-the line acceleration should I expect to lose?

How many fewer miles should I expect to get on my gas mileage?

I expect some change, especially since the tires are nearly 20 pounds more ea. and an additional inch taller. I just don't know how much. I am wondering if maybe I should just get the BFGs in my same stock size...even if they do look small.

I didn't notice any difference in performance when I went from my 30 inch OEM tires to 33 inch BFG's. I have not corrected my speedometer/odometer so I can't accurately figure my MPG's. I doubt if you will notice any difference.

I doubt you will notice any/much power loss. The tire is only about an inch taller, which doesnt equate to a whole lot for performance.

I seem to be the only one complaining about 285/70R17 performance. Most people don't notice.

What was your stock tire size?

If you had 255's or something like that, then you will probably notice.
But if you go from 265's to 285's, (as you said) most people wouldnt really notice.

I went from the stock ORP/FX4 size of 265/70R17 to 285/70R17.

How much does the gear ratio matter???

I checked the old window sticker that I found in my glove box and it looks like I have a 3.55 LS. From checking other posts, it seems like larger tires drops your ratio...is this correct?? I do a lot of highway driving...so I don't want to affect that aspect too much.

Also...in my research, I have come across an interesting dilemma. I have been finding other trucks with tires under the name of 'Wild Spirit - Radial RVT'...but I can't find anyone who sells them. Who makes this type of tire??...and does anyone have any input on their quality.

Thanks

I went from 265's to 285 BFG Mud Terrains.
I noticed a decrease in accelleration. Nothing big mind you, just that "seat of the pants" feeling. I can live with it because I couldn't take those tiny little factory doughnuts anymore :rolleyes:

I also have 5.4, offroad, tow package and 3.55LS in case you are wondering.

Just another .02 worth for ya.

I have the 4.2 V6 with 3.73 gears and I didn't notice any loss at all. I went from a 255/65R17 to a 285/70R17.

I went from the OEM Wrangler 265/70/17 to

BFG A/T 285/70/17 and didn't notice any difference in power at all. Gas mileage seems to be the same as well

-slippy