2008 T4R Limited V8 4x4 - How much difference in gas mileage from 5w30 to 5w20?

[bigwebb83]

are you guys quoting cold pressure or after the tire has been rolling and warmed up a little?

 

[webby]

are you guys quoting cold pressure or after the tire has been rolling and warmed up a little?

In my experience, tire pressures are ALWAYS quoted in cold pressures after the vehicle has been sitting for a few hours, ideally first thing in the morning. There is too much variance in pressure after having driven around -- outside air temperature, load of the vehicle, air pressure in the tires and so on, for air pressure after having been driven to be reliable.

 

[Koz]

There is only one way to fill your tires, cold!

Koz

 

[bigwebb83]

this may be a silly question, but with it 20 degrees outside and me needing to drive about 5 or 10 minutes to put air in the tires, how long should i let it sit to get to a point where i can consider them cold?

 

[M1911]

this may be a silly question, but with it 20 degrees outside and me needing to drive about 5 or 10 minutes to put air in the tires, how long should i let it sit to get to a point where i can consider them cold?

Longer than you are willing to wait. Just give it an extra pound or two.

 

[OrdnanceMarine]

this may be a silly question, but with it 20 degrees outside and me needing to drive about 5 or 10 minutes to put air in the tires, how long should i let it sit to get to a point where i can consider them cold?

What you could do is check the pressure in your driveway (cold) and note how many PSI you want to add to each tire. Say you're down 3 PSI in the front and 5 PSI in the rear. Then go and add 3 in front and 5 in the rear to whatever you see at the place you're filling it. Other option is to buy a cheap 12V compressor at Wal-Mart, Costco, etc. and keep that in your vehicle. There a a good number of choices for under $30 with features like shutting off when they reach a desired pressure, etc. Having a compressor also sets you up to give someone a hand when you're helping them change a tire and it turns out they have 8 PSI in their doughnut that's supposed to have 60 PSI.

 

[bigwebb83]

just a quick update. Temps are back up to a toasty 35 degrees or so here in kc up from single digits. I also installed the K&N filter (paper filter was completely clean by the way). I also inflated my tires which were 34-35psi cold up to about 38-39psi (will probably back that down just a hair). Anyway just some preliminary tests on the highway with cruise control on today and the computer (yes i know it can't be trusted) is showing about 19.3 mpg at ~72mph up from 16.8. So I think the temperature was really making a big difference and the tire pressure probably helped too. Not sure how much to attribute to the filter but I like the sound anyway

 

[OrdnanceMarine]

just a quick update. Temps are back up to a toasty 35 degrees or so here in kc up from single digits. I also installed the K&N filter (paper filter was completely clean by the way). I also inflated my tires which were 34-35psi cold up to about 38-39psi (will probably back that down just a hair). Anyway just some preliminary tests on the highway with cruise control on today and the computer (yes i know it can't be trusted) is showing about 19.3 mpg at ~72mph up from 16.8. So I think the temperature was really making a big difference and the tire pressure probably helped too. Not sure how much to attribute to the filter but I like the sound anyway

What I can say about the computer's MPG counter is that it is consistent. My current tank is the first one that has any meaningful amount of off-road and a bunch of stop-and-go and cold starts bringing the computer's reading down to the high 19 MPG range. My ScangaugeII continues to read 10% below the computer, matching the difference I was seeing on the previous 4 tanks that were mostly highway. While it lies about your MPG, at least it lies consistently!

Air filter won't make a difference in your MPG. For the record I have done oil analyses on my '00 Accord three years ago before I sold it and it was running a cold air intake with a K&N cone filter and the amount of silicon was nominal. Granted, I wasn't off-roading my Accord but it was run in the upper Mojave Desert, with lots of dust and sand to contend with on a ~9000-mile oil change.

 

[liqourish]

I'm not trying to turn my 4runner into a civic. I can afford it just fine. I do care about the mileage though. Especially when I read about members on here getting 20+mpg with mostly highway driving. I think my problem is a combination of a few things. The temp has been single digits since i bought the vehicle and regardless of what some may think letting air out of the tires improves traction (you don't just magically sink through the snow all the way to the pavement) and i thinkn the tires will be under inflated when i check. I also plan on the air filter, synthetic oil and synthetic diff and transfer case fluids. I think all of this plus normallizing temps (especially as temps warm up in March) will bring me up 2-3 mpg. We shall see though.

i dont think anyone is actually getting more than 20mpg unless they weighed less than 100 lbs. and if anyones getting near 20, it must be new.
IF anyones is reading off the dash, subtract ~1.8mpg and itll be right, then if they have lift,cargo, tires factor that stuff in
getting 18 with all my mods and freezing temps. and people on this forum empasized things way too much on tires. its only a small factor for those with larger tires. and lesser for those with near stock tires.

 

[bigwebb83]

another update. I got on some flat roads today and set my trip in sync with the mile markers (marked every .2 miles) at first it seemed to be right on but then after about 5 miles it looked like my odometer was just a tad on the slow side, meaning that if those markers are correct that my odometer is showing a little less than actual mileage which would mean my hand calculations are a little low. Any thoughts?

 

[OrdnanceMarine]

another update. I got on some flat roads today and set my trip in sync with the mile markers (marked every .2 miles) at first it seemed to be right on but then after about 5 miles it looked like my odometer was just a tad on the slow side, meaning that if those markers are correct that my odometer is showing a little less than actual mileage which would mean my hand calculations are a little low. Any thoughts?

Measure with a GPS on a longer road trip on open roads. My odometer reads miles a little longer than they really are as well. About 2% if I remember off the top of my head. The ScangaugeII that I use has been corrected so it reads the correct distance and the correct fuel burn, therefore giving me true MPG, to within .2 gallons on a fill. I need to fill up again today-tomorrow so that will be about the 6th data point I have to validate my results.

 

[bigwebb83]

just a little to add here. I changed my oil to synthetic 5w30, installed k&n filter, seafoamed the engine, changed diff fluids and transfer case fluids to redline synthetic and filled the tires to 38psi. I took about a 20 mile drive on the "highway" yesterday. Here's the thing though, it wasn't my typical highway driving where its open road with the speed limit at 65 or 70mph. It was at the end of rush hour about 6pm where the speed limit was between 45 and 55 with a few stoplights thrown in there and traffic was still pretty thick. I did all the coasting I could at stoplights and never went above 58mph. I know the dashboard readout is almost useless and is usually about 2mpg off but I was showing over 22mpg at the end of this 20 mile trip (i reset at the begining). My point in all of this is to say that if you do all of the little things that can make a marginal difference and then keep the SPEED DOWN (if safe) then you can get 20mpg with the v8 4runner.

BTW this was in 29 degree weather and the crappy winter gas mix here in KC so I can't wait to see what I can manage in the spring time.
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