I learned a few interesting things today...

First up... with my factory Goodyear Wranglers... 85db @ 55mph ... 86.5db @ 75-80mph. Tires were set to full load pressures 47/50psi, checked before the drive.

With the Falken AT4Ws ... first up on comfort pressures (34/37 psi). 85 db @ 55mph and 87 db at 75-80mph. Second test using full load (47/50psi). 84db @ 55mph and 86 db at 75-80mph.

My thoughts here... I could hear the tire noise (it is different, mostly notable when slowing for a stop), I was certainly listening for it, expected it to be louder, assumed it was and without measuring anything stated so above. I was wrong. I also assumed that comfort pressures would be quieter (also wrong, quietest under test as measured was actually the Falkens at full load).

I do know these tires are heavier but I didn't measure that since while I have an spl meter for tuning my stereo I don't have a scale that would work for weighing tires. The Falkens are obviously heavier though because it was a pain in the butt putting the spare on--there is an obvious weight difference from a 19" wheel to the 20" ones with these bigger tires.

I paid close attention to the steering wheel on all of these drives, held with a very light touch I didn't notice any vibration in the wheel at any time with any of the tire configurations... I was expecting something from the heavier tires, especially when stopping but didn't note anything. Perhaps the Defender steering is well isolated and it is harder to notice or perhaps there just wasn't any to speak of with well balanced tires/clean wheels.

All measurements were taken with the SPL meter up near my ear, elbow resting on the center armrest, C-weighted, slow response. The same road was used for all tests, same sections of road used for all tests, no wind to speak of, 50F temps ... and I used an out and back route and checked the levels both ways just to be sure it wasn't the wind/grade of the road causing something to be different.

 

Old thread, but since I just went from AT3 in XL to AT4 in LT I can confirm that there is a pretty dramatic hit on mpg from 19.5 to 15.1 over a thousand miles now. I got the LT because the XL had worn very quickly (maybe 17K miles) and the LT is all they had in stock. I actually like the ride of the LT’s more than the XL which surprised me. At heavy load, cornering is firm, and less squirmy than the XL despite the larger tread blocks. I’m guessing it’s the thicker sidewalls. I wouldn’t run these at lower weight rating since the load rating for D range LT’s is measured at 65 lbs, and would be only marginally safe at 35 psi for the Defender. Still, 15 mpg sucks and I’ll probably go back to XL’s when these are toast even though I do tow a light camper sometimes. This might even compel me to get a Rivian at some point as I’m sick of burning all this fuel.

 

Low MPG (at best 15 highway) here with my load range D AT4s as well. Much of that I had attributed to my full size Front Runner rack and the 80mph highway speed limits around here which really suck down the petrol. An EV truck wouldn’t love these high speeds and the cold weather/snow so it isn’t even worth considering.

The AT4s have been a pretty solid all around tire though despite getting a bit louder as the miles go up (10,000 or so on them now). These D range tires likely still have more tread on them than a new set of XLs given they started with an 1/8th inch more in the first place as I recall.

 

Much heavier tire all around. More tread, thicker sidewalls. Question is, is the hit on mpg worth it. Depends I guess. A Rivian with max pack is probably in my future either way. My oceanographer daughter is shaming me for driving such a ridiculous gas hog and she’s right. 15 mpg is just stupid in this day and age. Rivian gets plenty of range for my needs.

 

Keep an eye on the new Scout. Looks like it will be a bit bigger than the Defender, which I don’t need, but it’s intended to be an off-road capable EV with a gasoline range extender. I’ll be looking to replace my Defender when those come out, and if they work well off road, it will be a tempting option.

 

Do you need the heavy off-road capable all terrain tires for a specific reason? Because an EV is really not going to like those anymore than the Defender. Since mpg is a primary constraint for you the factory spec tires (not duratracs) should be your first choice as JLR spends a significant amount of time and money making their fleet mpg as high as possible and their specified tires are a large part of that.

Just because it isn’t petrol going in the tank doesn’t mean that you’re not using a lot of energy to push the vehicle around. An SUV with off-road capability is a choice to use far more energy than a small car. If your oceanographer daughter is making you feel guilty then another large and extremely heavy (max pack) SUV isn’t moving the needle compared to a smaller and lighter commuter vehicle.

 

We do a fair bit of light off road and have to deal with class 4 roads in Vermont on many occasions, along with carting around a light camper. I know all these things require more energy than driving a small car around, but for now we are just trying to do what we like to do more efficiently. Even though the Rivian will use more energy than a smaller EV, we have lots of solar and can charge it basically for free at home (solar is a sunk cost for us) and even a large EV has a lower carbon footprint over 100K miles than an ICE car. I’ve looked at the Scout but it’s too damn big, and I don’t want to drive a solid axle vehicle on pavement. Also have no interest in hauling around two engines like in their harvester which will get lousy mileage when the generator is running. The extra range on gas isn’t worth it to me.