JDMCQ's Garage

91 is recommended on the 4.0 for maximum performance and fuel economy. There is a 1-3 mpg difference recorded using 91 vs 87.

 

I've not seen any impovements either way and infact got 23.4 mpg on 87.

 

I run 91 in the summer for the 1-3 mpg gain, 87 in the winter because fuel economy is gonna suck regardless.

 

Blasphemy!


j/k

As I have never had a 4.0, I just go with what hthe forums tell me.

 

I actually run 89 with the 10% Ethanol all the time because it's $.15 a gallon cheaper all the time. I still get 20-21 in the summer and 17-18 in the winter. even better if i can slow my ass down to 65 on the interstate.

 

Also looking at a local 2000 'Runner. Only 127,000 miles.

http://delaware.craigslist.org/cto/3646065723.html

 

It says it comes with a rear differential, didn't know that was optional on those year runners

 

It would get me close to my original plan. Older 4Runner for winter/trail/Lowes duty and down the road get a sporty sedan for DD/work use.

Don't matter if I cannot get rid of the Liberty.

 

With all this talk about it, I had to figure it up.

Figuring 3.65 per gallon for 87 and 3.95 per gallon for 91. Running 87 for 350 miles at 18 mpg would cost you $70.97. If in fact 91 nets you 2 mpg; running it at 20mpg for 350 miles would cost you $69.13. Running 91 in this scenario would net you $1.84 over 87 per fill up.

 

Morning Lisa, John, Juice, Adam

 

87 @ $4.24/gallon (17 gallons = $72.08)
91 @ $4.80/gallon (17 gallons = $81.60)

87: 17 MPG, 17 miles x 17 gallons = 289 miles
91: 19 MPG, 19 miles x 17 gallons = 323 miles

87 $/mile = $0.249
91 $/mile = $0.252

 

i dunno....maybe?

 

Of course it depends on the prices

 

edit: just realized we both did more steps than necessary, easiest way to calculate it would be $ per gallon / miles per gallon

 

Shh. don't tell Cindy.

 

I have been experimenting with 91 lately - I am getting about 2mpg more than with mid-grade (89 I think). In the long run, 91 should be better for your engine, right?

 

With a 2 mpg increase and a .30 per gallon difference, the savings is marginal.