Gas mileage...good-bad (The Mother thread)
06-25-08, 06:35 AM
#334
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mine 93 LS400 with 135K performed as follows...
Running on conventional oil 10W30
18mpg average 85% highway, 15% local
After oil change to 10W40 synthetic
21mpg average same commute
I now get extra 60 miles per tank after the oil change!!!
I'm about the change the plugs next to Bosch Iridium to see if I can get even more.
Running on conventional oil 10W30
18mpg average 85% highway, 15% local
After oil change to 10W40 synthetic
21mpg average same commute
I now get extra 60 miles per tank after the oil change!!!
I'm about the change the plugs next to Bosch Iridium to see if I can get even more.
06-25-08, 07:34 AM
#335
absolutely unfair and not applicable to the guys driving 1st gens :P The 1st gens get terrible gas mileage compared to the 2nd gen; generally at least 25% worse
anyhow with good driving and no modifications my '96 with 250k has seen 30mpg on the highway.
the LSs with the best mileage are probably the 98-00 model, with the extra gear in the trans and the vvti, but they also cost a solid amount more than the other models
not a knock on the 1st gen - the 1st gens are wonderful solid cars that are in some ways better than the 2nd gen - its just that they indulge in a little more gasoline in any given mile driven
anyhow with good driving and no modifications my '96 with 250k has seen 30mpg on the highway.
the LSs with the best mileage are probably the 98-00 model, with the extra gear in the trans and the vvti, but they also cost a solid amount more than the other models
not a knock on the 1st gen - the 1st gens are wonderful solid cars that are in some ways better than the 2nd gen - its just that they indulge in a little more gasoline in any given mile driven
my in-Law drives a 1999 and he gets 1-2 MPG better than mine so I feel the pain
06-28-08, 06:48 PM
#338
1991 lexus ls400 206,000 miles running 87 octane 19 in town 23-25 on the highway put in idirum plugs at 204 ,000 miles and mileage jumped 2 mpg. Something of interest no difference in mpg from 91 octane to 87 octane and no pinging I am suprised that 87 octane didn't ping there could be a slight difference in power but not to much difference.. Gas being used arco which a lot of people say is not the best gas but after pulling my platium plugs with 102,000 miles they were gray and no build up normally are changed at 60,000miles.
06-30-08, 05:51 PM
#342
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My story is much like Bill Dowd's. I use 87 octane and I honestly can't tell the difference between that and "the good stuff", although there may be a subtle change. I have used 87 for over a year and a half and have had no problems at all in a '97 LS 400. In town, I generally get about 19+ mpg and on a trip it will vary from 23 to 27+, depending on conditions like wind, rain, etc. I use 5/30 Mobil 1 extended change synthetic oil. As far as I know, it has the original plugs.
Try it -- you'll like it, the savings, that is.
Try it -- you'll like it, the savings, that is.
06-30-08, 09:42 PM
#344
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27.5 Mpg
I'm surprised by the figures posted in this thread. I highway commute in Los Angeles and average 27-28 MPG. My best mileage on a tank is close to 29. I always get over 500 miles on a tank, my high is 590, and today I filled up after 560 miles.
Granted, I drive like your grandmother and keep the cruise on about 68 MPH.
My 98 LS has 180k on it. I use dino 5w-30 oil, the cheapest 91 octane I can find and the car has had no modifications. Nor do I overinflate the tires, though I may try it.
I will say that when I bought the car at 100k the mileage was horrible - 17 or 19 like I see many posts state. I had the car undergo a fuel system flush to clean the injectors & valves. The hesitation stopped and the mileage bumped up significantly. I strongly recommend a carbon clean fuel system flush to boost mileage.
Granted, I drive like your grandmother and keep the cruise on about 68 MPH.
My 98 LS has 180k on it. I use dino 5w-30 oil, the cheapest 91 octane I can find and the car has had no modifications. Nor do I overinflate the tires, though I may try it.
I will say that when I bought the car at 100k the mileage was horrible - 17 or 19 like I see many posts state. I had the car undergo a fuel system flush to clean the injectors & valves. The hesitation stopped and the mileage bumped up significantly. I strongly recommend a carbon clean fuel system flush to boost mileage.
