Careful inspection of the tread confirmed what I’d thought upon initial scrutiny: It’s obvious which pair of tires had been on the rear axle of the turbo-diesel Cummins and which had been on the front. The rears were evenly worn but had about 2/32″ less tread than the fronts, an obvious result of the substantial diesel torque, loading, and type of use they received.
The additional tread in the centers of the fronts was nice, however the outer edges were unevenly worn due to poor front-end alignment, driving style, or both.
Below you can see there is 10/32″ of remaining aftermarket siping in the center lugs.
My friend Paul recently referred to Craig’s List (CL) as “the end of the internet”, and I found it both funny and appropriate. Paul says he and his brother Chuck will visit their favorite sites, and then end up on Craig’s List looking for deals. A recent CL find in a nearby town seemed worthy of investigation…
“Almost new Maxxis Bighorns, paid $900, only asking $600, still have the nubbies on them”. Since I’ve used and enjoyed Bighorns before, and had a naked set of wheels begging for new rubber, I called and got the skinny. I was told the tires had “about 1,000 miles on them”, from a few trips to the neighboring city, taking kids to school, etc. The guy said he would take $500, sounded genuine, so I decided they were worth a look and made the 1.5 hour drive one morning.
1,000 Miles x 5
Exiting my truck with my tread depth gauge in-hand, the first tire I measured had only 15/32″ tread in the center. I showed the seller, who used to work at a Les Schwab Tire store in Idaho, and he responded with: “Wow, I didn’t realize they were wearing that fast”. New 285/70R17D Maxxis Bighorns come with 19/32″ of tread, and though they can be a fast wearing tire, there was no way they lost 4/32″ in 1,000 miles, even on the rear of a powerful turbo-diesel with a young right foot driving them. During further discussion one trip from Nevada to Idaho and back was mentioned, and from the wear I guessed the tires had logged at least 5,000 miles. The fronts had more tread in the centers but the outer lugs were feathered from poor alignment or driving.
Since I needed more tires like the preverbal hole in head, and wanted to insure I could resell them if the the Tundra or I didn’t like them, I told the seller I didn’t want to offend him, and then offered him $300. He said he wouldn’t go that low, and that there was a much better market for his tires back in Idaho. I increased my offer to $350 (add $50 in gas to that), and said I understood if he didn’t accept, I enjoyed the drive and would be on my way. He and his wife tossed it around for a few minutes, and then accepted my cash.
Loaded, strapped down, and heading home, I stopped for a cold drink at the local gas station, it was a warm spring day. I took a few pictures of the new toys, had a snack, and watched a tow-truck driver try to perform a lockout on a new, 5th Generation 4Runner for over a half-hour. This reinforced the value of my practice of always carrying two ignition keys, one in each front pocket. It’s been a very long time since I’ve been locked-out of one of my vehicles, more than sixteen years.
While driving home I planned the mount & balance and test-drive with the new to me Bighorns.
Driving in the wind can be a drag, particularly if you’re driving a high-profile vehicle, hauling a camper, or pulling a trailer. We live in an area that often has wind, and unless it’s coming directly from the rear, wind is an impediment to good fuel economy.
A perfect, direct tailwind is like the perfect anything, nice to dream about but difficult to find and enjoy. In the real world roads twist and turn, and wind swirls and comes from multiple directions. If you’re on a one-way trip with a direct tailwind, embrace and enjoy the smooth ride.
Strong headwinds are of course the worst, but lateral winds also inhibit forward progress and add to the always-present aerodynamic drag that increases with speed and reduces miles-per-gallon. Ascending hills consumes fuel, particularly if we insist on charging them at full-speed, but driving in strong winds can be like constantly driving up a grade. Of course it’s not just wind that reduces fuel economy, other weather conditions can be a drag too, heavy rain, snow & slush…
Heavy Wind MPG Impact
Over the past month two lightly loaded trips to pickup and deliver cargo reinforced the impact wind can have on highway fuel economy. Though not to the same destinations or on the same highways, the distances were very similar, and both trips were mostly on rural highways with which I am very familiar. Both trips included a few minor passes and grades, though I would not call the routes mountainous, relatively level for around here. In my mind, the first trip should have produced better fuel economy, though both were through areas that are often windy, and during trip one it was extremely windy. On both tests my top speed was the same 65 miles-per-hour, though the second test did include some two-lane highway with a lower limit for several miles, mostly 60, which improves fuel economy. There were very few stops and starts.
Test Vehicle: 2011 Toyota Tundra, lifted with Old Man Emu suspension, 2-inches in the rear, 3.75-inches in the front, LT285/70R17D Dick Cepek F-C II tires, tailgate removed.
Trip 1: Reno, Nevada, to Susanville, California, via U.S. Route 395.
181.2 miles / 11.142 gallons of unleaded = 16.26 mpg.
Trip 2: Reno, Nevada, to Mason, Nevada, via I80, U.S. Route 95 ALT.
172.1 miles / 9.979 gallons = 17.24 mpg.
The mpg trip computer in this Tundra has proven quite accurate much of the time, though when the second test was completed the PCM was pessimistic, indicating 16.9 mpg. We always calculate and record our true mpg, and compare it to the PCM’s readings. The math doesn’t lie, but liars do math. Speaking of liars…
Over the last few days many news sources were chanting that the gas price surge of 2012 was over. They quoted Patrick DeHaan, senior analysts for gas buddy.com, who said, “By the behavior of the market, things are just running out of steam”… unless there is a major political event to reverse things, he thinks prices have peaked. Many websites are carrying this story and I’d be thrilled if he’s correct, $4 is plenty for my wallet.
With a little digging I did find alternative views, including the federal Energy Department that predicts that prices will still be 6% higher during the peak driving months of April–September 2012. These predictions are based on higher crude oil, which is down a little as I write this.
I don’t follow crude oil prices, I follow the price at the pump and the miles from each gallon, something I have some control over through careful shopping and driving. I hope the fuel surge is over, all of us would welcome fuel below $4, and below $3 would seem relatively inexpensive these days.
Anyone holding their breath waiting for a return to sub $3 gas?
Yesterday I received an email forwarded from an acquaintance regarding an AOL story which references an AutoTrader.com survey. The survey was about at what price per gallon car buyers will significantly consider a vehicle that offers better fuel economy.
The AOL headline read “Car Buyers Won’t Change Habits Until Gas Hits $6.51 A Gallon“. After reading the article I immediately went looking for other views… One blog I found commented how the sensational headline didn’t match the facts of the article, presenting a slated view of the data from survey if one were to stop at the headline.
According to the AutoTrader survey data, fuel would have to be over $6.51 per gallon before 35% of respondents would “seriously consider a vehicle that got better fuel economy”. Another way to look at the article is that nearly two-thirds would seriously consider a vehicle offering better mpg before fuel reached $6.51 per gallon. The AOL article also quotes different experts about citizens already making decisions influenced by the current higher prices, or just getting accustomed to our higher fuel prices.
Our Lower Threshold
With our little fleet of vehicles fuel economy has always been important and is tracked with every fill-up, even the motorcycles. This doesn’t mean that we are rabid hyper-milers, but we have always had a healthy awareness of how much fuel we burn and what it costs. Long before fuel reached it’s current high price near $4, fuel economy was a factor when we considered adding or subtracting horsepower in our stable. We like and use trucks and four-wheel-drives, not just because they are cool or became trendy, but to haul and pull things, and to go beyond the blacktop.
I will likely remain a truck guy instead of a car guy until I can no longer afford to operate and enjoy them, or change hobbies and lifestyle. When my wife and I purchased a new pickup last year, fuel economy was certainly a consideration, but not the only deciding factor. While we would have preferred the slightly better mpg possible with a Toyota Tacoma or similar smaller truck over the Tundra that was chosen, the potential fuel economy improvement was not worth the inability to haul and pull larger things, and do big truck work. Added to this preference for full-sized capability is the fact that we already have a mid-sized utility vehicle, another mid-size would be redundant.
Mixed with our 4WDs are two very economical daily-drivers, one two-wheeled, one four, and the four-wheeler gets about the same (sometimes better) mpg as the moto. As shared recently in the TDI Mileage Test post, our little VW Golf diesel is a very valuable daily driver. In recent years we’ve been casually watching the automotive market to see what we might want to purchase when it’s time to replace the TDI. We have considered some AWD cars, but their fuel economy is typically so much lower than the VW/Audi TDI that they’re not serious contenders for our dollars. We like being road travelers, even in a car, which means keeping at least one very high mpg four-wheeled vehicle in our fleet for daily driving, weekend errands, and car trips is a nonnegotiable.
Fuel prices are already high in my opinion. With a fixed amount of dollars budgeted for fuel each month, higher fuel prices mean driving less, getting better mpg, both, or deficient spending—which is not allowed here.
Where Do You Stand?
What is your number? Are you part of the top third who won’t seriously consider a more economical vehicle until fuel is $6.51 a gallon?
Will The Most Efficient Tires Please Drive Forward
It’s often stated that narrower, lighter, less aggressive tires are more efficient and will yield better fuel economy, but how much better? To properly compare apples and pears one must take care to reduce the variables that are always present during real-world tests. In this case I used the same vehicle, same gas pump, during similar weather conditions and time of day, calculated the odometer error, and used the same section of freeway. The GPS-confirmed road speed was 64-MPH and was maintained by cruise control. The tires were inflated to 35-PSI in all but the last test with the Dick Cepek F-C II treads where I goofed and only used 32-PSI. The F-C II tires performed so well I doubt they could have provided better economy with an extra 3-PSI.
If you think the fuel economy numbers listed below are too high you are partly correct, the tests involved almost zero city driving. The variables of in-town driving are not repeatable and won’t yield consistent data. What these tests do show is the fuel economy potential of this vehicle and establishes a baseline against which other tests can be measured. For each test the modified 2006 4.7L V8 4Runner was fueled and then driven a few blocks to the same freeway onramp, onward to a specific exit, and then the route was reversed and terminated at the same gas pump where the engine was promptly turned off.
All the tires used were close to the same diameter, about 33-inches, and they were all mounted on Toyota FJ Cruiser TRD 16 x 7.5-inch aluminum wheels. Because of the slight differences I tire height, one corrected odometer reading of 56.76-miles was used for all the tests. Listed below with the figures are the weights of each tire/wheel combination.
Cooper S/T LT255/85R16D: 75-lb 3.027-gal. = 18.75 MPG
TreadWright Guard Dog LT285/75R16E: 87-lb 3.331-gal. = 17.04 MPG
Dick Cepek F-C II LT285/75R16D: 83-lb 3.121-gal. = 18.18 MPG
I was a little surprised that the very narrow and light Coopers consumed more fuel than the heavier, more aggressive Maxxis Bighorns. Though when filling-up after the Cooper test the gas-pump didn’t stop normally and a little gas spit from the filler, possibly contributing to the lower reading. Longer distance tests would likely be more accurate, but this type of testing is very time consuming and expensive.
It was expected that the heavier, wider TreadWright Guard Dogs with their aggressive lug tread would use more fuel. The Cepek F-C II tires impressed me by splitting the difference and topping eighteen MPG!
Surely tread design, width, and weight all make a difference. My theory is that width and tread design have a larger impact on fuel economy than tire weight, at least when there is only a few pounds difference. There is five pounds separating the Maxxis Bighorn 255/85R16 and TreadWright 285/75R16, but I don’t think those additional few pounds account for the 1.77 mile-per-gallon difference. There is a seven pound difference between the Maxxis Bighorns and Cooper S/Ts, but the results for these two 255s were so close you could call it a tie.
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