New tire size and some math questions

[hat_man]

Thanks again everyone.

I had a feeling it might be a trade off. The aggressive tread pattern will help this winter. I know this sounds crazy for someone posting here but I almost don't mind losing 1-2 mpg for the better grip. I know it's only a few months for winter but I have heard good things about the tread wear and road noise in good weather too. I can take that in trade for the peace of mind. Maybe I can gain some of it back with my next mods. I'm looking at re-doing my front grill block and adding an air dam. That and bypassing my A/C compressor. I'm still investigating trying to lower the truck 2" in the front and 2" in the rear. That may now be possible with the taller tires but it looks like I have lots of room in the wheel well. I'll just have to make some measurements with how far the wheels travel while at full turn and see. Still....30mpg fairly consistently with a 17 year old truck is pretty darn good. Let's hope these new tires don't lose me to much.

[BabyDiesel]

Originally Posted by hat_man

Thanks again everyone.

I had a feeling it might be a trade off. The aggressive tread pattern will help this winter. I know this sounds crazy for someone posting here but I almost don't mind losing 1-2 mpg for the better grip. I know it's only a few months for winter but I have heard good things about the tread wear and road noise in good weather too. I can take that in trade for the peace of mind. Maybe I can gain some of it back with my next mods. I'm looking at re-doing my front grill block and adding an air dam. That and bypassing my A/C compressor. I'm still investigating trying to lower the truck 2" in the front and 2" in the rear. That may now be possible with the taller tires but it looks like I have lots of room in the wheel well. I'll just have to make some measurements with how far the wheels travel while at full turn and see. Still....30mpg fairly consistently with a 17 year old truck is pretty darn good. Let's hope these new tires don't lose me to much.

Nothing wrong with not maxing out your efficiency. Most here are not looking to redesign their entire vehicle for max FE, but to improve on their current ride. If your life requires you to sacrifice a lil' mpg for certain reasons, then do so and improve on what you have to live by

I have done research in the past on FS D A/T's as I was looking into them for my truck (they were the cheapest all terrain by far). The info that I found over and over was a slight decrease in FE, around 1 mpg from highway tires.

Recovery modding is a good mindset. All those should add up to an increase and you'll have better FE than before! Just slowing down by 5 mph would probably balance out the effects of the A/Ts.

[Tabour]

Hi,
If you know the distance travelled, (you said you do this daily) and the amount of fuel used to travel that distance-it's simple division.
Or find the same size tyres as the factory used-they are available!
As the tyre revolutions per mile are less you WILL get better fuel economy, BUT you will loose take-off power (torque) due to the diameter of the tyres being larger! (In your case THIS IS NEGLIGIBLE if the engine is healthy)

[hat_man]

Just returned from a trip on the new tires. I must say I am impressed. I haven't run through the whole 10 gallons yet, but at 220 miles (on the odometer) with approx 2 gallons left it looks promising. At first blush it seems the increased final drive and increased weight were a wash. I do notice the need to downshift on hills though. I figure it's the heavier tire and rim combination. But it seems I can coast a bit further. Would the heavier tires/rims be acting like flywheels?

As for the tires themselves they are rather smooth and quiet for A/T tires. Very rainy and I had good grip all the way home. No hydroplaning or slippage on corners. A little roll on hard corners but I drive conservatively most of the time. 55mph for the highway stretches and unfortunately lots of "in-town" driving as someone seems to have played with the settings on my GPS.

All in all I am happy with the new tires. I'll report more on how they do in the snow and if I lose any mpg the white stuff gets here.

[hat_man]

OK. Just returned home from a 500 mile trip. 90% highway and 10% in town. I kept my speeds at 55mph and the posted limits in town. Had a tail wind for the last 90 miles, but it looks like I'm at 31 mpg. Maybe a little more as I STILL haven't fixed the leaking filler neck. I am still very impressed with the smooth and quiet ride of the A/T tires. They had great grip this winter. The only thing I changed for this trip was I did the coil pack mod. For those who don't know this one you can read about it here.....

Ford Ranger Forum - Forums for Ford Ranger enthusiasts!

It seemed to help with take off and climbing hills. I wasn't down shifting as much and take offs were a bit quicker according to the butt dyno. I have to wonder about the increased clearance. I think I need to finish my air dam to keep some of that air out from under the truck. That and fix that filler neck so I can get some accurate numbers. Has anyone here done an airdam and side body skirts? Not wheel skirts but ones that run along the body below the rocker panels. Do they help or do they only have minimal impact?