I just put on a set of H2 wheels with the 315's. It sure does look sweet, but it knocked my mileage down about 2mpg. In my mind, 10% is a fine price to pay for the way it looks now. Just a warning though...nothing comes for free.

 

what gears do you have?

 

Did you recalculate for the bigger tires?

 

http://www.sjdsm.com/tech/tire_size.htm

RJ

 

Yeah, but now I can run over slow people in small cars hogging the left lane.... Seriously, I think the 315's I have are the biggest I will put on my truck. Still handles okay, but I can tell that I would have to put a lot more effort to keep it in my lane if the tires were any bigger....

 

315 Bfg = D.w

 

Did you have the PCM reflashed to the new tire size?

 

= death wooble? I don't have death wobble with my 315's. Where did you come up with that?

 

I'm running 315 Coopers, and I have no issues. The truck has a leveling kit on the front and the 315s sure look good!!

 

It is a little more work to keep it in the lane--that could be due to the leveling kit though. I did the ol' cell phone calculator and tripometer method for coming up with my number. I've dropped from around 20mpg on the highway to 17.9 on my most recent traffic-free trip from Pasadena to Laguna Beach. I put some Pro-Comp ES9000's on there too, and with the addition of the bigger tires, it rides a lot better. In my book that's two (looks and ride) for and one against (mpg) the new tires. I'm happy with it.

I have the 3.55 gears, I'm sure if I had 4.10s the mileage would have gotten better.

 

I have 4.10s and went from 295's to 315's and my mileage is ~ .5 mpg less with the 315s. (I did correct my odometer reading with both sizes, btw)
I think the actual tire itself has alot to do with mileage results. For example, the tires in my sig weigh 76#s apiece, while a BFG AT in the same size weighs 67#s.

 

I have the same combo, itonly affected mileage around town. you have to add he mileage lost from not having corrected the speedo. roughly 5 miles for every 60. if im doing my math correctly. I also thought mileage wouldbe better on teh highway being lower rpm, but it likes to be around 1900 -2000 rpm and with 3.54's your moving

 

I think what DNR Customs was trying to say is that 315's equal death wobble. Perhaps not on the better design 03 and up since us 2nd gen'rs can upgrade to the 3rd gen trac bar. I think his comment may have been more toward us 2nd gen'rs putting on 315's as it is already weak in the front and adding 65-75lbs of tire out there will only increase your percentage rate of having the death wobble all to yourself.

 

I've had 315's on my truck for a little over 100,000 miles (161,333 on the clock now) and have never had a problem with the front end shaking. My track arm is pretty much worn out, but no wierd handling problems. I've got a 2 inch leveler on the front too.

 

My speedo is off about 10 percent with the 315's according to the garmin gps. That would make the milage you lost back up if it's correct for your truck.