Where are you from?

 

Even if I could fit 35's (or 315's), I would not unless I had 4:10 gears, which I don't. I have 3:55's and 285/75/R16 mud tires, and I'm actually looking to trade my tires for someone's 265/75/R16's. It just seems bogged down to me now, even with just 285's on it, and I'm only getting like 13.5 mpg, so i'm going to go down to 265 like was on my previous truck. Won't look as good, but I'll be happier with daily driving and towing, and the MPG should be better. Plus, the ones that are on my truck now are mud tires, so I think that makes it a little worse too.

 

See i do have 4.10s, and im running 235/85/16 rught now which are just ridiculously small, even for stock. And for my to achieve 75mph, im at about 2800rpms.

 

That does make a tremendous difference. Those tires are small! Bill has 285's on his truck with 4:10 gears, and I think he's probably running about 2400 or 2500 to get 75 MPH, somewhere in that range. If you put 35's or 315's on there, then you'll probably be a little below that, I would think. With my 3:55's, I run about 2000 RMP @ 65mph, and probably about 2300 at 75 MPH. Much lower, but if I put bigger tires on mine, it seems like I lose tons of power and fuel pedal response. I think I'll be happier with 265's. I do have a 50hp tow program on mine right now, and that helps out a lot. I was running it in stock and felt like I could get nowhere.

 

Ive got 315/75/R16 with 4.10s and im at about 2200 at 75.

I get about 17 highway.

 

I'm just out of Yreka which is on I-5 about 20 miles south of the Oregon border.

I just put 315's on my 7.3l and didnt notice much of a power difference. There was an rpm drop of about 100 rpm's at highway speed. I have 4.10's also.

 

It makes it more sluggish because with a bigger tire diameter lowers the torque to the wheel. (think if trying to spin a broom by its handle). my old f150 had 4.56s and 315s i had a ton of torque for having the 4.6.

 

well guys, got the axle in finally!! took about 10 hours to do. i want to post pictures of what it looks like now... but i dont know how?? haha any help?

 

Boy,I just can't believe you don't do better.but for one I have 3.55,285s,auto.69mph @ 1900 rpm...17 around town with NO tuner. 75mph 2200 and mileage is better,not sure since I have not refueled that tank yet. With a programmer and the almighty stick(lol) you should have plenty of power...sure something isn't wrong with the engine?

 

Thats simple gearing mechanics, the higher the gears(lower number) the less rpms, along with the bigger the tires the lower the rpm, with 3.55gears and 285 tires (33 inch tires) your gearing is very high causing very low rpms, were as i have low gears and 31s which makes my gearing super low. But im sure you already knew all of this!

 

Yep.i just cant believe tyler gets such bad mileage.his speedo is off...my truck sure does not seem to suffer from too tall tires.

 

I know. There may be something wrong, but it hasn't ever really acted like there is. It runs good, though not as smooth as my old green truck ran. It has developed a slight surging idle, which Bill just fixed on his truck with a new IPR, so I plan on replacing that sometime in the future. Other than that, it actually runs pretty good. I can't figure out for the life of me why it's getting such horrible mpg. The tires were my first thought. I just don't know. It's disappointing only getting 11-13 mpg. I like seeing 16-18. Wish I could get there again.


Let's see some pictures of that axle LittleBlue. I've always posted mine to an album (go to your User CP and you'll see the option for albums). Then you can put the link to the picture in your album in your post.

 

You need a photo hosting site like photobusket, image shack, etc.

I am curious to see your "shackle drop"

 

Alright ill figure out how to get that. that will be the first picture i get up is that shackle drop for ya. id have to look at the paper work from the prvios owner of where he bought it from. but ti will be up soon

 

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