mkeeney

So is the vibration only happening under certain conditions? If you're not feeling it during steady driving at highway speeds, I don't think it's the tires. Are there any other condition when you feel the vibration?

Does this mean it only happens when you hit the brakes, not any other time?

1. If the mechanic wasn't inclined to make money fixing it, you can most likely trust his opinion. You can take it to another shop for another opinion. You can take it to a Lexus dealer and they will definitely give you a (very high) price for fixing it. The car is not going to explode from an oil leak. You should check your oil level more frequently though to be sure it's never low. 2. If he said it was engine oil then that's probably what it was. Transmission fluid will be a different color, usually red. There is no reason one would cause the other to leak. 3. Our '97 ES300 has leaked for the past 100,000 miles (230k now) from the rear main seal. It's a tiny drip that doesn't even cause the oil level to be low between changes. It sometimes drips on the exhaust pipe and causes a burning smell. As long as it stays small like it is now, I'll never fix it because the cost is too great compared to the inconvenience it causes. I just check the oil more often to keep an eye on it. Yours sounds similar. 4. We got an estimate of about $1200 a few years ago for our rear main seal. It requires pulling the engine. Without more info or seeing photos, we can't speculate on what might be causing your leak. You didn't recently have your oil changed, did you? Sometimes those guys get sloppy.

The only real advantage synthetic oils offer is that the viscosity breaks down slower than conventional oils. This allows you to go longer between oil changes, sometimes up to 12000-15000 miles. If you're diligent about changing your oil at regular intervals and you're not brave enough to extend the mileage between changes, stick with a conventional oil. There's no reason to use synthetic if you're going to change it at 5000 miles. If you're going to use synthetic for extended intervals, you need to pick a brand and stick with it, and send the oil off to have it tested in order to determine the best interval for your vehicle and oil. Our '97 ES300 has 230,000 miles on it with conventional oil. It still runs like it's new. This is a blanket statement that can't hold up to scrutiny. All of the synthetic oils out there are good oils. Some oils are better for particular engines under certain circumstances, but under different driving conditions, another oil may be better. Which one is the best depends on many variables that are hard to quantify and in the end don't make much difference anyway. As long as you are using a name-brand oil and changing it at regular intervals, you will never have an oil-related problem. Go here for more oil info than you can ever absorb: Bob is the Oil Guy

You can probably find a drop-in replacement here: Parts Express Their technical assistance can probably recommend one.

No, at the temps and pressures car tires see, the number of molecules will be roughly the same for nitrogen and oxygen at the same pressure. They both generally follow the ideal gas law at those conditions. Seriously, there is no difference between air and pure nitrogen in passenger car tires. Our R&D department never used nitrogen, even though we had a 40,000 gallon tank full of nitrogen on-site, and they were testing high-performance W- and Y-rated tires. How long has it been since you had an alignment? If the alignment is bad enough it can cause the wheels to throw the weights. If nobody can solve the vibration problems with traditional balancing, you might try road force balancing. Click here to locate a shop with a machine near you. I highly recommend the Kumho KH16 tire. We're on our second set because my wife loved the first set so much. They're quiet, ride great, handle well, and they're about half the price of comparable tires. I've had Michelin, Pirelli, Bridgestone, and Kumho on this car ('97 ES300, 230k mi.) and the Kumho's are far and away our favorite.

Having read the entire thread I'm compelled to address the nitrogen issue again. Please listen to what the other posters have stated in this thread about nitrogen - it is a gimmick for tire shops to make extra money and it will make absolutely no difference at all in passenger tires. Any difference you have felt has been your imagination, a placebo effect. My car feels peppier after I wash it, but I know it's just because I'm happier driving it. For background, I am an engineer with both tire and nitrogen generator experience. I've worked for two tire manufacturers and I've used both liquid nitrogen and nitrogen generators. I'm not bragging at all, but I do know what I'm talking about. The only reason nitrogen is used at all in so many industrial applications is that in the process to remove water vapor from air the other gases, mainly oxygen, are also removed. It has nothing to do with the properties of nitrogen vs. oxygen. Remember that air is already 78% nitrogen. The reason that water needs to be removed from aircraft tires is that those tires see temperatures of -40F and then a few minutes later have to immediately support the weight of an aircraft landing at 150-180 mph. Those tires heat up very fast, and with those temperature extremes, it would be impossible to guarantee the tire would have the correct pressure in it to support the aircraft if there were water vapor in the air used to inflate it. If the tire is underinflated, it will overheat quickly and likely fail during landing. Nobody wants to see that happen. Race cars also use nitrogen for the same reason. The pressures are tightly controlled for optimum handling, and they see similar temperature differences. The tires are stored at ambient temperature then after they are changed during a pit stop they immediately are run at race speeds, 180 - 220 mph, depending on the series. It's the immediate temperature extremes that makes removing the water vapor necessary. Your car tires never see those types of extremes, so it can't benefit from ultra-dry air. Pressure is pressure, no matter if it is generated from 78% nitrogen or 99.5% nitrogen, so whoever told you that 35 psi acts like 40 psi or vice versa was only trying to sell you something. Others have already covered the fallacies regarding corrosion.

I don't see any reason to replace them if they are working fine. There's no guarantee that a replacement would last any longer than what you already have. Wait until they break.

Having worked as an engineer at a major tire manufacturer, I definitely recommend using H-rated instead of V-rated, unless you plan on driving for extended periods above 130 mph near the full rated load of the tire. Sometimes, tire manufacturers make identical tires and change out the sidewall plate to read V instead of H. This means the H tires are really V-rated, while the V tires cost more. Since the UTQG treadwear rating is the same, it's likely the same tread compound. At our plant, we had exactly one tread compound that was used on all of our tires whether they were rated V, W, or Y. The speed rating has much more to do with the carcass construction than the tread compound. I have only used H-rated tires on our ES300 in the 140,000 miles we've had it.

Well, it's certainly a way for its sellers to make a lot of money off desperate people looking for a way to save gas. However, until someone puts out verifiable proof that it works, I label it as a scam. There is no such thing as HHO. It is either water, H2O, or separate gases, H2 and O2. The electrical energy needed to separate the water into hydrogen and oxygen is greater than the thermal energy gained when hydrogen burns and combines with the oxygen to again become water. Combine that with the inefficiency of using your engine to generate the electricity and you'll likely see a small increase in gas consumption. I suspect that the amount of water actually converted is small enough to be a negligible drain on your alternator, and therefore the amount of hydrogen actually burned is probably also negligible. Do not accept anecdotal information from the internet as proof that it works, i.e., some guy writes "My gas mileage went up 3 mpg." The only proof is independent lab testing done by someone like SAE, which I have not been able to find.

My first impression is that it's a bit of a gimmick, and that any additional power is going to come from the less-restrictive air filter. There's not enough information on their web site about the design to see if the principle actually works. It appears to be two parallel tubes, which is actually more restrictive than one tube of the larger diameter. They don't explain how they actually cause the velocities to be different in the tubes. They don't show any comparison power graphs from different dyno runs. Why? Don't they have them? They have videos of various cars during their dyno runs, but nothing to indicate the effect of their intake. Their photos of their vacuum test show plastic tubes, not an intake. Why? Velocity, pressure, and flow are all related, but they make the blanket statement that higher vacuum always equals higher flow, which is not true. It also indicates a higher restriction upstream of the gauge. Think of a shop vac with the suction end plugged. I am skeptical because there are simple, inexpensive tests they can perform to prove that their intakes work better than others (i.e., stock vs. weapon dyno runs), yet they offer none of that on their site. Without proof of dramatic power increases, I would pass on it.

I would start by cleaning the engine so you can see where the oil is leaking. We have a leak on our rear main seal the drips onto the exhaust from the front bank. We never see any smoke, but we can smell it when we park the car in the garage. It leaks less than 1/2 qt. between oil changes, so I have no immediate plans to fix it. Yours sounds like a bigger leak, but before anyone could recommend a solution you have to know where it's leaking.

Tom, I have to ask, why wouldn't a key job on this car have anything to do with the door lock circuits? The 92 ES has a remote button on the key which directly interfaces with the automatic locks. If you download the manual from this site you'll see an entire section on programming this key--it is highly electronic and very much tied into the power lock actuators. I'm not being sarcastic, I just want to know what your perspective is that one should presume no electronic liability during a "key job" for this vehicle. Programming the remote doesn't involve doing anything electrical to the car. It is simply a manipulation of the ignition key, the door locks, and remote - all normal everyday operations - in a specific sequence to tell the car to recognize the remote. They didn't take any wires loose, didn't connect anything to the car, didn't take any panels apart. The remote sends a car a signal which tells it to unlock the doors. The remote cannot ever cause a fuse to burn out. The fact that the fuse burned out at the dealer was purely coincidental. It could have happened at any time.

Did it start when you got the new tires? Tires aren't perfectly flat across the tread and one side may be bigger than the other. There is a spec for conicity on tires and OEM tires are held to a higher standard than replacement tires. Try swapping the two front tires to see if it pulls the other direction to rule out the tires. You may have a bad tire.

I'm going to attempt to adjust the valves on our '97 ES300 in the coming days. I'm having a terrible time finding anyone who stocks the shims. My local Toyota dealer told me they've never adjusted the valves on a V-6 Camry, and the closest Lexus dealers do not stock any shims. They let the car sit until the shims come in when they do an adjustment. Does anyone have any suggestions on a shim source? I'm told by the Lexus dealer that one of the bucket lifters is stuck and worn causing the tapping noise we're hearing. They diagnosed this by listening to the engine. The valves were actually adjusted at 154,000 and one of the front lifters was replaced then. The car has 186,000 now. They were willing to help me out with a discount on the work, but not enough to make it worth it. I'm going to try to find the worn lifter and replace it then check to see if I need any shims. Are the valve adjusting tools useful or can the adjustment be accomplished with other tools? I've read through all the threads dealing with valve adjustment but I'd appreciate any advice anyone would like to offer.

I replaced the display on our radio following the instructions found in this thread: Link I got the display directly from the Pioneer link in the thread. Nobody could touch their price. It took less than an hour to replace the display.

The vehicle is programmed to accept the remote. I don't know how many it will store, but our '97 currently has 3 remotes that work with it.

Try ebay too. They're usually on there. The car is actually programmed to accept the remote, so it doesn't matter where the remote came from, as long as it's compatible.

That's not actually a plunger. The valve rotates, so instead of pushing that piece in, rotate it open and closed as you spray cleaner down into the slot in front of the throttle. I just did this job on our '97 this past weekend. I actually removed the throttle body and the IACV from the TB. It took about 2 hours from start to finish, but I was going very slowly and taking pictures as I went. I didn't have any difficulty removing the IACV screws after the TB was out. I think it's worth the extra time and trouble to remove the TB and IACV to completely clean the valve after seeing its condition. Mine does have 184,000 miles on it though, and it was completely black.

Your first step should be to go to an auto parts store and buy a manual for your car. My manual by Haynes was $17 from Autozone and worth every penny. It's actually a Camry/Solara/ES300 manual. The manual describes most procedures and includes photos, so it makes it easy. Even if you end up not doing the job yourself, you'll at least have more knowledge about what someone else does. As I recall, the only way to correct the IACV problem is by cleaning it by hand. If after reading the manual you don't feel comfortable doing it yourself, you should look into finding an independent service center or a Toyota dealer to work on your car. There's really nothing unique about a Lexus.

Yes, I'm an engineer. I design tires for off-road equipment - excavators, tractors, loaders, etc. I don't mean to be combative at all. I just don't want anyone paying extra money to put nitrogen in their auto tires thinking they're going to see a world of difference in their performance. If you're happy with nitrogen and Costco does it for free, then continue using it. However, the best thing you can do for your tires is keep them properly inflated. Nitrogen doesn't reduce heat buildup- proper inflation does. You're far better off to refill your tires with moist air than to drive them under-inflated with nitrogen.

Nitrogen is less dense. Like I said before, I have extensive engineering experience in this area. I've used nitrogen generators for gas-assist injection molding and in high-pressure off-road equipment tires. I've spent a week in technical training at one of the largest suppliers of nitrogen generators to the U.S. Navy for use on aircraft cariers. You can choose to believe me or not. The effect you feel at passenger car volumes, pressures and temperatures is purely psychological. Costco has a good thing going there for themselves.

Unless you are able to drive in a perfectly straight line on a perfectly flat road, your center differential is constantly adjusting between the front and rear axles. That's the whole purpose of a center diff., and the size difference between worn tires and new tires is not enough to affect it. They are trying to sell you additional tires. I'd try another shop. Use the spare and the new tire on the vehicle and use the decent tire left over for the spare.

A lot of the parts are the same, but it's best to check the part numbers. I have called the Lexus dealer and gotten the price and part number for a part I needed then called the local Toyota dealer and gotten a price based on the part number. It has always been cheaper. Some dealers won't give out the part number though.

I'm an engineer in the tire industry. I've worked for a major passenger tire manufacturer and now work in off-road tires. I can assure everyone that using nitrogen in passenger tires is completely a gimmick. As others pointed out, the reason it is used in racing, aircraft, and large excavators is that the membrane process of removing the water vapor from the air also removes the oxygen, leaving only nitrogen. You are far better off to regularly check your air pressure than to think about replacing your air with nitrogen. As for your car riding or driving better with nitrogen in the tires, my car is always a little peppier after I've washed it. It's purely psychological.