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mindmachine

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    2008 RX 400h

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  1. Hi Tom,, The foundry is the worst, we are lucky here in a way because our foundry was closed years ago, but I do remember many people had respratory issues. The smoke from the foundry was a kind of reddish-rust color and it plummed out over a large area. Cars parked outside were covered with the dust if they were in the wrong spot almost anywhere in the city, depending on the pervaling wind that day. I don't know for sure, but I imagine rail dust is not quite as bad because it isn't released up high in the air like the foundry smoke stacks and therefore will not drift so far from the rails. I worked for the company and one reason they closed the foundry was because of the cost to contain the particulates, the EPA was cracking down and new scrubbers were going to be needed. We made large internal combustion engines, up to 20,000 BHP and Jet Gas turbine driven compressors. We had more than one foundry and we closed the one in Ohio and keep the one in PA open. Eventually we even closed the one in PA, but it stayed open at least another 30 or so years. I worked in the manufacturing engineering department where we continued here in my town to machine the castings and assemble the finished product and still do. Cast iron dust is still a problem to contain in machining and finishing operations, but the EPA has mandated many restricitions on what can be exhausted to the atmosphere outside the plant. Still though if you live close to a machining or metal finishing operation and they don't properly scrub their plant exhaust you could experience the rail dust phenemon with metal particles in the air from a cast iron machinig and or finishing operation. Dennis
  2. Yes that is what I use, I keep thinking Corrosion X,but Rejex it's the same company they also make Corrosion X but it's for untreated steel if I remember correctly, and I use Rejex on my car instead of any other wax product. I have been using it now for 5 years. You are correct it is not a wax but a liquid product that creates a polomer bond to protect the paint, it looks and acts like a liquid cream wax. It creates a really smooth finish just like wax. Dennis
  3. Actually you may be only partially right. Last year before I took delivery of my just delivered special order Lexus 400h I visited the dealer while they were prepping it. They were actually washing it by hand with a special solvent and I ask them why. The service technician doing the work explained that he was removing rail dust, he further explained that since the cars are shipped from the west coast by rail to Chicago they get covered with rail dust and if it isn't properly removed it will show up just like the way the person who started this thread is experiencing. He further explained that not all dealers follow this proceedure. I think he actually told me they use a diluted mild acid, not sulpheric or hydrachloric, I can't remember, anyhow he told me they then rinse with another solvent, wash with a car soap and then wax. Now this is on a brand new car shipped in from Japan and rail shipped from the port on the west coast to Chicago for trucking to Ohio. Also if the person lives in Michigan close to a Foundry, cast iron or steel then the same thing can happen, we used to have a cast iron foundry in town , and while its not rail dust per say, it is iron particulates in the foundry exhause that then settles ou on a cars paint and does the same thing. Many people in town had their cars damaged from it. It is the combination of these conditions with acid rain in the midwest that is real hard on cars. Corrosion X is a good way to protect your car paint from this problem. I use the Corrosion x wax to do my cars now and haven't had any problems. I do my car every 6 months. Dennis
  4. $1200 Prices for all options are listed on the Lexus web site.
  5. I guess I didn't know that mechanical Engineering would encompas all there is to know about rubber chemestry ... and how those varrying chemestires react under different loads and temperatures and durations and manufacturing techniques when mingled with other materials, or how the extra torque created by dual electric motors (as the AWD has), and extra battery weight has to be taken into account, comparred to the porsche/bmw / lighter suv's. My crazy thinking is that since a tire &/or auto manufacturer has express and implied warranties, that those kinds of responsibilities would carry more weight, than say if some shloemoe like me posts a thread that contradicts. I mean after all, if I'm wrong, buyer beware, right? Heck, even the tire companies don't know everything ... or am I the only one who remembers the SUV roll-over fatalities atributed to Firestone tires. http://www.detnews.com/specialreports/2002...restonetire.jpg Well let me try to explain my point, but first let me say what we have been discussing are mechanical properties, not chemical. Load rating, speed rating, tread wear, temperature rating and traction ratings are all mechanical properties. Also let me say that you dont have to be a chemist in engineering to understand mechanical capabilities of materials, in fact in collage I had to take courses such as "strength of materials" which involved the analysis of different materials which included their mechanical properties. I also had to take several chemistry courses, but no I am not a chemist. I do however understand things such as how the durometer value of rubber varies with its ability to withstand deformation and resist tearing (tensil strength) and how it will wear depending on the ammount of silica is in the rubber and how long the carbon strands are for example. My background, well, I worked for Monsanto for a short time after I graduated from collage, but left them to work for an I C engine and Jet gas turbine manufacturer for the rest of my career. I worked in Research and Development part of my career and then in mmanufacturing engineering and quality troubleshooting. While I am not claiming to be an expert on this or any other subject as this is just a talk forum to exchange ideas, experiences and preferences. My reference to being a mechanical engineer was mainly however directed at my understanding of how the tires are tested mechanically in a lab, tolerances and safety factors vs the statement that skyfish400h made that I should reread how the speed rating is established in the lab. Well I hate to scare anyone, but many ratings on other products are done the same way. Specifications are established, testing techniques are usually applied in a lab for example under controlled and repeatable conditions. Running the tire up to a speed for a duration of time without failure establishes a parameter for comparision. Even if you did the test on the road under actual conditions just how long would you drive an actual vehicle at 149 MPH + to determine if a trie was capable of a Z rating, until it blows out. I guess skyfish400h would do that. Sorry I feel ornery. Finally to answer your questions 1.) The OEM standard equipment 17" tire is rated at 101 S, so that establishes the load rating that the vehicle needs and that is my point. Lexus as timid as they are when it comes to product liability (ie not allowing us to access the navigation while moving) believes that the 101 load rating and S speed rating which is 112 MPH, is sufficient. remember the 18" wheels are optional and so Lexus decided to go for a higher rated performance tire to appeal to customers who want that, not that it is necessary, otherwise the standard tire would have had a V rating too. 2.) I already ansewered your question on chemestry, we have been discussing mechanical properties, including your traction motor torque coment which just results in more tire wear do to slippage of the tire. Just like on the drag strip more wheel slipage more abraded rubber. What I did on my 400h, well personally I agree with BillyShaft, I consider all the same aspects he mentioned in his post in much the same order, size, load rating, wear number, speed rating, temperature rating, traction rating. I purchased the Bridgestone Alenza 235x55x18 100 V. Granted it is an all season tire but what I was looking for was the wet and snow traction without the need to purchase a dedicated snow. I do understand what you were trying to get at with your chemestry comment, today tires are more complicated than they used to be, but again the chemestry like long strand carbon filamants, added silica, dual durometer/variable chemestry tread layers ect., are only elements that vary the mechanical performance properties of the tire/rubber. Beyond that I agree its a personal choice and there are trade offs and a little common sense is needed when selecting your tires. So far we have not discussed tread design and how higher performance tires while they grip better usually dont wear as well and dont ride as nicely. Lastly our 400h's aren't comparable to either BMW or a Porsche Cayenne in the performance and suspension capabilities. Therefore some of these tire choices are over kill and potentially wasted money on the 400h. Well I had better stop this is getting way too long.
  6. Its not a good idea to put too much emphasis on the literal definitions for the speed ratings. They are only benchmarks for comparison. When you see 130mph, and think to yourself, "I would never drive an RX that fast, and neither should anyone else"... you are missing the point. It's a capability, a safety factor, a margin for error, a tolerance. It's something I would rather have than not. Re-read the laboratory conditions for how they determine those speeds and all of the caveats they put around those ratings on the tirerack link you sited. And think again about the real world conditions they have to operate in. find out :o ) Actually I am not missing the point but I think you are. I am a Mechanical Engineer and I understand tolerances, safety factors , testing methods and all that you mentioned! I say again you dont need a V rated tire on the RX400h, and I again say the load rating is more much more important than the speed rating unless you plan on driving your RX400h on the autobahn at 130 MPH for long stretches of time. Oh did you know that the OEM 17" tire that comes standard on the RX400h is a 101 S rated and if you didn't read carefully that is rated at 112 MPH. So in light of that fact I am 100% positive in knowing that the V rating on the 18" OEM's is not out of necessity. One more point, the RX400h is electronically limited to a top speed of 112 MPH. hence the standard equipment tire rated at 101S. How many SUV makes and models do you know of that have a top speed capability equal to the RX (112 MPH) and come with V rated tires. Lets take the 07-08 Acura MDX for example since it uses the Michelin Latitude, a tire which comes in several different speed and load combinations. For example the Acura is fitted OEM with the 255x55x18 104H when they could have used the the same size 105V that is used on Mercedes or even the 109V XL which is used on the Porsche Cayenne. Heck even BMW does not use the V rated option they fit theirs with a 109H. Now I know the RX 400h is a peppy SUV but it does not compare to the Porsche or BMW when it comes to being capable of being driven at high speeds and in agressive driving situations. :chairshot:
  7. You do not need a V rated tire the H rating is sufficient for any RX400h driver. What is more important is the load rating. The speed rating V is good for a maximum speed of 149 MPH and the H is good for 130 MPH. I dont think the 130 MPH limit is an issue on the RX 400h. The load rating is based on the ammount of air the tire holds along with construction, like the number of plies and steel belts. I have a set of Bridgestone Alenza's that I took off of my Acura MDX just before I sold it, they are rated 109 H XL, they are extra load the same tire without the XL in that size is going to be 104 or 105 load rating. I sold my MDX when I bought the RX 400h and yet even though I had these tires with only around 400 miles on them I bought the correct size Bridgestone Alenza 235x55x18 for the RX 400h. If you are interisted in the 255x55x18 Bridgestone Alenzas I still have them , contact me. I currently have them on a set of Acura MDX wheels but they could be unmounted. I am planning on posting the wheel and tire set on ebay this spring. Look on the tire rack as it explains load and speed ratings in more detail. Hear is a link to that info: http://www.tirerack.com/tires/tiretech/tec...?techid=35& In other posts over the last year or so some have commented on having rubbing problems with the 255x55x18 in various tire makes. Look at the clearence in the rear wheel opening between your tire and the spring mounting plate. Also the rear fender liner. Its very close and depending on the individual fit at the factory some have experienced rubbing under certain driving conditions. Personally I replaced the factory tires with Brigestone Alenza's 235x55x18 and am really satisfied with them. They are 100 V rated which is slightly better/ heavier load rating then the OEM Goodyears or Michelins. They feel like more tire than the OEM and performance wise according to customers that have purchased them from the tire rack, the perform much better in most areas then the OEM Goodyears and even the Michelins. I myself, dont believe in oversizing on the diameter, and on a car like the RX 400h with close clearences I am not even big on increasing the section/tread width. Anyhow good luck with whatever you pick.
  8. Do the math, the 255/50/18's are only .51% undersize. thats only 102 miles extra in 20000 miles or 255 miles extra on 50,000 miles, not really a big difference in my opinion. Many dealers will give you a few miles over the max anyway. :chairshot:
  9. You are very wrong in your statement about fuel economy. I do however agree that premium does not have any more energy per gallon, but it is burnt more effeciently if the engine is designed for premium fuel. The Lexus engine is designed for premium and in the 2008 manual at least it even calls for premium. The problem in using regular is the anti knock system automatically adjust the timing to compensate for lower octane fuel and this in turn requires the enging to operat at less than optium design conditions and hence the loss of effeciency and this in turn lowers the fuel economy/MPG. If the engine were designed for regular, ie lower compression ratio, them the loss of effeciency would not occour since the timing would not have to be retarded to avoid premature combustion/detonation. In this case, the use of premium would not increase fuel economy nor would it improve performance either. I have written responses to this issue many times, it amazes me that people cant grasp the fact that the issue rests in the design of the combustion chamber and compression ratio and not in any energy difference in the fuel itself. I worked for a company in their I C engine research and development, I am a retired engineer and I can tell you without a doubt that an engine operating at less than the optimal design setting in order to avoide premature combustion (detnotation) is operating at less than optimal effeciency (ie lower MPG). So when the engine is designed for premium fuel the anti knock additives in premium allow the timing to run at the optim design setting/effeciency and the maxium energy that can be extracted from the fuel will be. One of my jobs while in IC Engine R & D was to facillitate combustion component related design changes in order to improve effeciency. We changed many design features like valves, and cylinder head configurations in order to alter gas flow and flame front flow patterns that would allow more effecient timing and hence improve effeciency. The engines I worked on were dual fuel and even tri fuel units, stationary power engines with much more horsepower than your Lexus, but the same engineering principles apply. The point of peek effeciency is a design point in every engine and it depends on all aspects of its design being utilized in order to achieve the design goals of both power and effeciency, fuel being a key component.
  10. I can't believe you are serious. That's your advise... listen to my iPod? Am I being punked here or what?:chairshot: Actually with all the previous discussion about the nature of the starter battery being too small and having very little reserve you should not be listining to the stereo or doing anything much at all when the car isn't running. Having severely chastized you on that point, LOL :o , I have a new 08 RX 400h I purchased in March, special order so I took delivery as soon as it arrived. Anyway I had the OEM battery drop below the min voltage once in October already and nothing was left on and no doors were open or anything that should drain the battery except the security system (the car was not run for a few weeks). Since I live 50 miles from the dealer I replaced the battery myself with the Optima Yellow Top # 51R deep cycle battery. I like you did not want to fool with the OEM's less than adequate battery. I called the dealer to ask them about the warranty on the battery and they told me it was not covered because I replaced it myself, said I should have called them and had Lexus roadside asistance come and either jump start it or tow it. I said like hell that doesn't make any sense towing 50 miles would have cost more than the cost of reinbursing me for the Yellow Top. The Yellow top was $ 149 plus tax and old battery core charge or trade in. Well next time I buy my next new Lexus Hybrid, when I am satisified with the deal, I am gonna say oh by the way you owe me another $150 for the battery I bought on this car after only 8 months of ownership when service would not take care of it. Good luck on whatever you decide but if you read other posts on here the Yellow Top is discussed in several other posts.
  11. My first post here, but long time lurking before I bought my 400h in June this year. To answer your question, I did not choose the NAV option since I don't need it. I used a hand held gps on a trip, but other than that, I know my way around town. Anyway, after I agreed on a price with the sales guy, I was taken to an administrator to sign up the deal. He asked me if I want to add rear monitor, radar for cruising (forget what they call it, but it is available in Toyota as well), and a bunch of other options. So, this implies that you do not have to buy the NAV package, but pick the individual options you need. All you have to do is a special order and get exactly what you want. Thats what I did on my 2008 RX400h. It takes 3 months to get it built to your specifications exactly. When I placed my offer, my car is already on the ship to Canada. So, my impression is that these can be added on by the dealer. The Nav system, rear camera, Mark Levinson are not options that can be added by the dealer!!! Take a look at a car with the Nav/bluetooth/rear camera option and then one without it. The Nav package requires a different dash!! Your dealer was probabally able to hijack another car in transit ordered by another dealer that fit your specifications.
  12. My first post here, but long time lurking before I bought my 400h in June this year. To answer your question, I did not choose the NAV option since I don't need it. I used a hand held gps on a trip, but other than that, I know my way around town. Anyway, after I agreed on a price with the sales guy, I was taken to an administrator to sign up the deal. He asked me if I want to add rear monitor, radar for cruising (forget what they call it, but it is available in Toyota as well), and a bunch of other options. So, this implies that you do not have to buy the NAV package, but pick the individual options you need. All you have to do is a special order and get exactly what you want. Thats what I did on my 2008 RX400h. It takes 3 months to get it built to your specifications exactly.
  13. I talked to the Lexus Dealer in my area just a week ago and like the others posted, I was told there would be no 2009 RX 400h, and that there would be a 2010 version redesign released in the Fall of 2009 and/or with deliveries not untill the spring of 2010.
  14. According to edmunds.com the changes are only a slight face lift! I quote a current article with spy photos just online this week " If you're hoping for big changes you'll be disappointed, as the next RX looks much like the current model in terms of its overall size and shape. There's a slightly revised grille up front that's more angular in appearance along with a reconfigured headlight cluster. In back, a new set of LED taillights is the most noticeable difference. There are a few minor changes to the shape of the rear fascia, but unless you put the 2010 model side by side with the current RX you would find it hard to see the difference between the two." A link to the article: http://www.edmunds.com/insideline/do/Gener...rticleId=129127 Another quote: " There won't be big changes under the hood, either. A revised version of the current 3.5-liter V6 will provide the power with a six-speed automatic handling the gearchanges. A hybrid model will be available as well" Kinda of more of what the 08 is but with a minor face lift and probably with an increase in price I speculate. I am glad I went for an 08. The pictures on inside line are not conclusive because the body is taped up to disguise the actual changes, but it is fairly easy to see the changes are indeed really minor on the outside. They did not say anything about the inside as they did not see it.
  15. Wow, been down this road before with the people on the Acura MDX forum. First let me say I am a retired mechanical engineer who used to work for an engine builder. Actually Cooper Bessemer. In my early days I worked in research and development as a technician while I was attending college on a co-op plan. Anyway to the point, we tested engines running in a steady state enviroment, constant speed and load for periods of time and we adjusted the timing to get optimum performance, ie fuel effeciency for the load. The engines I worked on were very large, the type used in electrical power generation and on compressor sites to move natural gas in pipelines. Typical engine configurations were as large as 12, 16 and even 20 cylinders and up to a maximum of 16,500 HP. These engines ran very low RPM and piston slap could be easily discerned. We did a lot of work on cylinder/valve configurations in order to achieve total combustion. As you might imagine fuel efficiency is very important on a 16,500 HP engine running all day long 24/7 pumping natural gas from Texas to Ohio for example. The companies like Columbia Gas Transmission want the best efficiency they can get. A little more background here and then to my point. The 2006 RX manual did not suggest you must run 91 Octane premium, also the 2006 manual recommended 5w-30 weight oil; but the 2008 manual says 91 octane premium is required, and they also changed the oil requirements to 5w-20 and as an alternate 0w-20. ok so what design changes to the engine have occurred, I can only guess. I could look at compression ratios ect and speculate but who knows for sure. Anyway back to the R & D testing and results: 1. Engines run most efficiently at the proper timing setting, retarding timing for any reason not only reduces available HP, it also reduces fuel efficiency even if you are not needing the extra optimal HP available at the optimal timing. We could always see the impact of less than optimum timing on fuel effeciency 2.In a large engine like I am talking about, piston slap really sounds terrible, when the engine knock occurs, its a loud and ugly event; but in a small car engine it isn't so loud and to boot it is deadened by other sounds, it is however just as damaging. 3.It's all in the design, how the engine is meant to be run, the compression ratio and the cylinder head design along with valve placement configurations. The gas flame front will advance differently and impact both maximum energy output and fuel efficiency, no matter what the load the design parameters of the engine cylinder, proper timing and yes optimum fuel based on the design/ implemented design goals. Now having said all that, we need to think about how the hybrid ICE setup works, yes it runs at in a more constant RPM range with a variable load. Also like others have said driving for best fuel economy, we aren't pushing the engine into the extremes in needed HP, but the interface of the ICE and how load is applied by the hybrid system is vastly different from a conventional gas engine only setup. Ping is of course going to be more noticeable and more prevalent when power demand varies more with a regular transmission, but that does not mean that the hybrid setup with a CVT doesn't encounter load variations that would cause piston slap-ping if it weren't for the electronic countermeasures retarding the timing as needed. Another point as I understand it, the electronic timing anti knock system is designed to reset the timing curve over a period of time, like when you switch gas from one tank to the next, instantaneous timing adjustments do occur, but the whole timing curve is only gradually adjusted as you burn thru a change in octane of a new tank of fuel. I am not a Lexus engineer so I am only speculating based on rumors I have heard. Also I will state now I own a new 2008 RX 400h and I use 91 octane premium, with $4 a gallon gas $0.20 is only a 5% premium and 5% of 27 mpg is only a 1.3 MPG difference and you break even. Plus I have the added comfort of knowing I can tromp on it if I want to,I can go up steep hills without worry, I can encounter really hot summer days with the AC running and indirectly loading the engine for needed electrical power ect. However, the best part is I can go the the Lexus dealer in the case of a warranty related failure and say I followed the recommended fuel requirement and my warranty should be good if needed. I know way too long, to summarize though, it's your $49,000/ $50,000 car do what you want to, my 08 RX 400h calls for premium required in the manual and it's only 5% more at todays prices and I am a mechanical engineer with engine testing experience, but I still cant totally evaluate how necessary it is or the total impact of not using premium. So I will error on the side of caution following the factory recommendations and enjoy the ride when I might otherwise worry. If I want to feel the power I can and I can climb a steep hills without having to reduce speed going up it without concern. I am older and not a heavy footed driver, I drive for economy most of the time. I still however find times when I want to use my car close to it's design potential.
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