Wicked_Lex

After throwing it up on the alignment rack, if that wasn't the problem have your tires spin balanced, you may have thrown a weight. Sometimes you only notice out of balanced tires at certain speeds.

They're both good cars that use the same engine. If you want the most comfort from a ride, take a lot of trips, and have the extra money for the heavier LS and its slightly higher fuel bills go for it. If you want better performance and handling and a ride that is good but not as much so as the LS go for the GS.

I've run it down to 'E' and I think a little below, though not by choice. You might have a gallon or more at 'E' but I wouldn't push it.

I agree with the others. If the tranny is in 'D' and you’re going down hill with your foot off the gas you aren't going to use much more fuel than idling. And, as others have said, coasting in neutral is illegal as well as dangerous. The best way to save fuel by coasting is to take your foot off the gas when you are a block or two from a stop light/sign in the city and a ¼ mile on the highway instead of gassing it and braking hard when you get there.

[ The car has 52K on it. I buy 93 for my car or in Mobil it's super. The car hasn't been tuned yet for anything major, Because my the dealer told me to come back at 60k before any tune up is required. I have changed all 8 Spark plugs to DENSO 4 months ago. I also do an oil change every 1500 miles with Mobil 1. I have just changed the air filters from stock to TRD 2 months ago. I also Don't drive with the tranny in power mode or use the select shift. Maybe it is because I drive local everyday, But I only use under 5 miles everyday from home to work and I do only go 30-44 when going to work. I just feel it's weird because GS 400 and 430 have 19.8 gallons on the tank and even if I do 10 miles per gallon I should still run 190 or up.. I'm at 65.4 now on the meter and I have used alittle more than 1/3 of the gas. Let's just say if I do have to go to Lexus to get the computer chip replaced, How much would it run me? Thanks guy you been alot of help. It sounds like you are doing all the right things but even in heavy traffic you should still get 4-5 more MPG than you are. The fuel mixture might be too rich, that is all controlled by the computer too. Does it blow any dark colored smoke out of the exhaust? If you have time you might take it out on the highway, set you trip odometer, fill up with gas, travel a distance at cruising speed, fill it up again and do the math. If your getting over 20 MPG there is probably not much wrong with the car. Otherwise I would go to the Lexus dealership. One more thing – hope that you don’t need a new ECU. I was reading one of the threads and some guy, not sure what model, said it costs - $3000!!!!!

I don't know much about the O2 sensor or how it would effect mileage but if you are in a lot of stop-and-go trafic you won't get good mileage. One of the most determing factors in MPG is the way that someone drives. When I first got my GS I was getting less than 200 miles per tank because I was doing a lot of 0-60 shots, and jamming the pedal down to get around slow moving trafic. Recently I took a trip from California to the Midwest , set cruise control at 75-80 MPH, and still got 25 or 26 MPG! Less than 200 miles on a tank doesn't sound right unless you're driving fast in the city. I think the GS gas tank holds around 18 gallons so you'd only be getting about 10-11 MPG. Just a few questions: 1) What is the vehicle mileage and when is the last time it was tuned? Fouled plugs, defective plug wires, and dirty air filters can rob mileage. 2) What kind of tire pressure are you runnig? Most tires recommend 32 LBS but I run mine at 35-36 because it coasts better and still gives a good ride. If you have one or more tires at 25 LBS or less you're wasting fuel. 3) What grade of fuel are you burning? There is a temptation to burn cheaper grades now that gasoline is over $3/gallon If you're not burning at least 91 octane in your Lexus you won't get the performance/mileage that the engine was designed for. A few other suggestions: Use synthetic oil - less resistance means slightly better performance and mileage Don't drive with the tranny in power mode or use the select shift. If none of this helps I'd go to your Lexus dealor and have them put it on a scope. You might have a defective computer chip. I hope that isn't the case, it might cost you a couple of paychecks.

1) black exterior with beige interior OR 2) silver exterior with grey interior I feel that the black exterior goes well with beige interior. The only problem is that dirt shows really easily on black exterior. I plan to keep the car in the garage at night, and I intend to wash the car about twice a month. Is black exterior a good choice then? The silver exterior seems to be easier to maintain, but seems to look plain as compared to black exterior. The grey interior doesn't seem to look as nice as the beige. My only fear is that with black exterior, I have to constantly clean the car. By the way, why is it that there are much more black exterior sedans for the Mercedes, but I just don't see much black exterior sedans for the Lexus GS? I have a Black/Tan GS400 and it needs to be washed at LEAST once a week even in the dry season. Dust and pollen collect quickly. I think black is one of the sharpest colors - IF - you keep the car clean and waxed. Also keep in mind when the car is older small dings, dents, and scratches will be more noticeable with a black exterior.

Any GS owners have racing stories to share? track/street? I only have a couple, neither one lasting more than 3-4 seconds before the other guy gave up. First race - I was in San Pablo, I think along the Richmond Parkway, and an IROC Camero pulled up along side of me when I was going about 30 MPH. We both looked at each other and jammed the accelerator at the same time. The IROC kept up with me for about a second until the GS kicked down and the variable valve timing started Kicking A**. 3 seconds later I was 3 lengths ahead and the IROC gave up. Second race – I was stopped in the right lane before an intersection and the right lane merged into the left about 50 yards ahead. A cocky-looking dude with an old school GM with a loud V-8, stereo, and 20 inch spinners pulled along side and ahead of me like he was going to crowd me out. I'm thinking 'just try it'. I put the tranny into power mode and switched OFF the VSC waiting for the light to turn green. Stock GS400s don’t come off the line too fast so I made sure I nailed quick on the green. Old school got caught with his pants down and jammed the accelerator as I was flying buy. He got smaller and smaller in the mirror and gave up after about 3 seconds. At the next stop he pulled along side of me and I could see him looking my direction. As I looked his way he turned his head abruptly and made a left turn. Once more Detroit is embarrassed by a Master Rice Machine.

As for additives, I can tell you what I have done for all vehicles that I have owned in the last 10 years. First, I add Super Slick 50 to the oil the first time I do an oil change. After about 2-3K miles I change the oil and filter. From that point on I use a synthetic oil and a good filter, changing both every 3-4K miles. Mobile 1 is good but there are other synthetics. Slick 50 and other oil additives cost about $20 and treat the engine for 50 – 100K miles by putting a Teflon coating on engine parts improving per-formance, fuel economy, and engine life. I put Super Slick 50 in a Dodge Dakota and after driving it 150K miles it still used no oil between changes! Synthetic oil reduces friction too, giving better performance/economy. Recently I drove my GS400 from California to the Midwest and averaged from 24.8 to 27.2 MPG at 75-80 MPH even though much of this distance is mountainous. If you do a lot of highway driving cruise control also saves gas as well as money spent on speeding tickets . A couple of other things to do to save gas that is getting more expensive:  Coast more by letting up on the gas sooner  Let the transmission shift up by leaving it in 'D' instead of '3' or '4' in ‘Power’ mode.  Check tire air pressure. You can safely add at least 3-4 lbs to the manufacturer’s suggestion of 32 LBS. I’d keep it under 40 LBS. There are other gas/oil additives that claim to boost performance/economy but I haven’t tried any.

I checked with the Supra store and they have an RMM 376 LSD for about $1500, which is a little more than I want to spend. Are there any other differentials that wil work that don't cost quite as much? If so where can you find them?

About 125 MPH in a 1967 Mustang fastback with a 289 high performance engine. About 115 MPH on a Triumph Tiger motor cycle in a 30 MPH zone. :o Not sure about the GS 400. I marked off 1/4 mile, put the hammer down and got up to near 100 mph and it was still in 3rd gear! Should do about 150 I suppose. If I ever get to the Bonneville salt flats or some long remote highway I'll find out.

I have a GS400 and I would like to improve 0-60 and 1/4 mile times. I have heard a lot about Swift's intake/ECU piggy back system. Their wesite boasts of 30 HP and torque gains. Is that realistic? :) Does anyone have any before/after dyno charts that they could share? I am also interested in what negative effects, if any, this system would have on fuel econony since premium unleaded is selling for over $3/gallon in Cailfornia. :cries:

I have 2000 GS400 Black/Tan with dark tinted windows. Some friends of mine have said it looks like a car that the Mafia or CIA would drive. It’s all stock except for Magnaflow mufflers and a K/N air filter. I don’t have any video of a burnout but I can tell you about one. Last year a friend of mine was visiting and he seemed a bit under whelmed by the GS400 so I thought I better impress him with a bad-!Removed! burnout. It was late at night and as I pulled up to a street light I noticed a bit of water splashed on the pavement from sprinklers. The tires weren’t new but still had some tread so I set to power mode for the tranny and shut off the VSC. The light turned green, I jammed the accelerator, the engine screamed and redlined immediately all the way through first gear, second gear, and most of third gear before the tires started to bite. The speedometer registered near a 100 and I was only going about 10 MPH!. The tires began to melt as rubber was instantaneously converted into a thick cloud of smoke spreading outward across 3 traffic lanes, and upwards to a height of at least 20 feet. The friend of mine was bracing himself on the dash and door and said “J***s F***ing C**** !” I continued this foolishness for nearly a block before I decided to save some of what was left of my tires for future burnouts. It was the largest rubber induced cloud of smoke that I’ve seen since the National Drag Races. There had been cars behind us that were completely invisible until I got far away when I could see them emerging slowly one by one the way they do in a dense morning fog. I got home a few minutes later and the tires were STILL smoking and there were pulverized bits of rubber like fine saw dust on the outside of the poor tires. Needless to say my friend was impressed after that. A few burnouts and weeks later I bought new Firestone Fuzion Tires that are wider with a lower profile. These HOOK UP quickly, no bad-!Removed! burnouts with these.