wandawoods

yup, delaying timing belt change on VVTi enginge of 98+ LS over 90K, it's roulette alright! let's just say you have 1 in 6 chances to get your valves destroyed. I've been thru that with a 93 mercede 400sel I used to own, it costed me over $4K to get it running again! the lesson is that you just don't take any chances with interference-type engine. the call is yours, though!

here we have it, that's a definate definition of non-interference (free running) engine. one question though, any chance a broken timing belt itself hits the valves and make them bent? wait a minute, just realize it's a stupid question. the TB is outside the engine block, no chance it will hit any valve inside the engine.

in fact, I heard from couple of service managers at local lex dealer stated both my 97 LS4 and 96 SC4 (the same gen-II 1UZFE) are NI engines. so different dealers can have totally different story which only flames the confusion. I will trust JP1 a lot more because he actullay cranks open the engine and do works on them. timing belt job only involves engine "exterior", so the Lex tech may not know engine interior details at all no matter how many times he has done it. just my $0.02

excellent! finally hear from JP1 who actually works on 1UZFE engines for living, and nails the answer down for all of us! :D

please elaborate! did your timing belt break? I totally agree that if it did and bent valves were the result, then it definately is an interference engine! BTW, my name is not "wanda", "wandawoods" is a street name, and I am a 46-year old male.

he did not replace the timing belt pullies/tentioner? or tentioner for serpentine belt (lexus calls it drive belt)? they are totally different parts. also, drive belt pully is easy to replace, but the tensioner driving the pulley is very difficult to change out because bunch of overlaping pieces, including alernator, must be removed 1st! a bad drive belt tensioner makes noise, however, it's really not that critical. in fact, I will worry more about whether he has changed the 2x CAM seals & 1x Crank seals or not! otherwise you are looking at 6~8 hours labor to replace the leaking seals down the road.

I used to think that! however, after seeing so many references on web search stating 95~97 being interferance-type because Lexus increased the compresion ratio from 10:1 or 10.4:1 since 95 model. now, I just don't know what to believe. BTW, the 'i' in the designation "VVTi" stands for "intelligent", not 'interference'.

According to lexls.com - there were lots of impovements from 97 to 98: - Redesigned front end. Changes to the hood, fenders, grille, front bumper, and front lights. - Discharge headlight became standard equipment on Canadian models and optional equipment for US models. - Slightly refined rear lights. - Outer rearview mirror was changed to reduce wind noise. - Wheels were redesigned and now have 5 spokes. - A retractable headrest was added to the rear center seat. - Another rear personal light was added to the rear quarter pillar area. - A leather & wood steering wheel and wood shifter were introduced as optional equipment. - VVT-i (variable valve timing-intelligent) system and the ACIS (acoustic control induction system) was adopted in the 1UZ-FE engine to improve fuel economy, improve performance, and reduce emissions. ETCS-i (electronic throttle control system) was also added to ensure excellent controllability of the vehicle and improve its comfort. Worlds first production V8 engine with VVT-i. - 290 hp @ 6000 rpm and 300 ft-lbs of torque @ 4000 rpm (vs 260hp/280ft-lb for 95~97) - The 4-speed automatic transmission was replaced by a 5-speed transmission. - Propeller shaft was slightly changed. - The differential gear ratio was reduced to improve fuel economy. 2 mounts were used on both the front and rear of the differential to further reduce vibration and noise. - The VSC (Vehicle Skid Control) system was added. - Suspension and brakes slightly revised. - The hydraulic circuit of the power steering system changed. - More work on the body and sound dampening material to further reduce vibration and noise. - An automatic headlight beam level control system was added to models with HID headlights. - A headlight off delay system was added to keep the headlights on for a set period of time after occupants exit the car. - A multi-information display was added to the instrument cluster to display vehicle data and warnings. The design of the shift indicator was changed. - An automatic recirculation system was added to automatically switch the air inlet mode in accordance with the level of concentration of harmful elements in the air. - An all-door one-touch auto up and down function was added. - A jam protection function was added to prevent a person's hand or other object from becoming caught in the door window. - A function to operate all windows was added to the door lock remote control. - Changes were made to the engine immobiliser system. The starter cutoff function was discontinued. The theft deterrent system was slightly changed. - The construction and operation of the inflator for the front passenger air bag was changed. - A garage door opener was added to the map lamp area. - A seat belt warning for the front passenger was added. The display method for the seat belt warning system changed from the illumination type to the flashing type. - A navigation system was offered for the first time as an option. - Some changes to the audio system. A diversity rear window imprinted antenna system started to be used. - Top speed = 149 mph; 0-60 = 6.3 seconds (vs 7.7sec on 95~97 models); 0-400m = 14.9 seconds. I've been kicking myself since I bought the 97 instead of 98 couple of years ago! the power gain (290hp vs 260hp, 6.3sec vs 7.7sec) itself worth the money! the HID/NAV/Clear head-light lense.... etc are very nice to have as well. also, stereo LED display issues are very common for 95~97. it's very unclear that whether 95~97 has non-interference engine or not, the oppions are 50-50 split!

may want to consider replacing belt tensioner for serpentine belt while your mechanic is at it, and everything is apart. that belt tensioner is covered by so many pieces, most of them must be removed during timing belt change anyway, so this will be a perfect timing to change it as well, regardless the state. otherwise if it starts making noise later on, you will have to remove bunch of stuffs to get to it: advance autopart sell it for $21.

that's why whenever you have any issues with your Lex, you do a search on these forums first, it may turn out some good tutorials left by lots of good folks here to take care of ur problems by urself at mininal dollars.also, check out lexls.com and lextreme.com, both long-time contributing members here offering good tutorials of lots of fixing-up's! you think $160 is expensive to fix the fuel gauge, try dealer! they will want you to replace the whole cluster for $1K+ for some minor components cost a few cents to manufacture! for your reference, I did left a tutorial 2-year ago to show how-to fix the fuel gauge issue: http://us.lexusownersclub.com/forums/index...owtopic=5822&hl

It's well established that GenI (90~94) is non-interference (free running) type and GenIII (98~00) is interference type. the big confusion is for GenII (95~97) I can see lots of referrences on web stating that since the higher "compresion ratio" (10.4:1) was introduced starting from 95 GenII, therefore they becomes "interference" type. I don't really know engine well enough to tell you whether this logic makes sense?! anyway, both Gates/Dayco web site specifically states 95~97 LS400 are non-interference, and all timing related parts are the same between 1990 and 1997 (I can certainly comfirmed that!). can't really image that GenII 95~97 could become "interference", and still using the same timing parts from Gen-I?! I hope JP Importz can come on line and clearify for us once for all!

if the repair has been done, do a carfax on your own car and see whether any "severe or major accident" has been recored in the car history. don't we always tell used car buyers to avoid this type of used cars which been thru major accident or been salvaged unless it's heavily discounted car and you know exactly what you are doing. anyway, diminished value definately can occur. I can image a "severe damaged" car such as severe frame damages prolly will be pretty close to the same value of "salvaged" vehicle which can anywhere from 30~50% below market value.

also, don't forget the "loss of value" because of the nature of damage been done. it will be subtaintially less than market value if you want to sell it or trade in. so if your insurance did want to fix it than total it, make sure you include "loss of value" in the settlement. as I recalled, 2 years ago, Statefarm lost the class-action, and sent out millions of reinbursement checks to policy holders becuase for years Statefarm excluded "loss of value" in accident settlements. out of nowhere, I received $3K+ check for couple of accidents occured over 7~8 years ago!

i've been thru timing belt chages for 94 LS4 (Gen I) I used to own and 97 LS4 (Gen II)/96 SC4 I currently own, all the timing belt job related components (including water pump, pulleys...etc) and precedure are basically identical and interchangeable. if 1UZFE in 94 was a non-interference engine, then 97LS/96SC couldn't magically become "interference" type! of course, when the VVTi version of 1UZFE started to appear from 98 model, it definately became 'interterence" type. was it the same service rep told you to put 'type T' fluid in your PS pump?

hearing something like this makes you really appreciate side-impact air bags equipped with GenII LS4. from picture, I can see you have a gen I LS. I also had my old 94LS rear-ended by a nissan van almost 2-year ago with my then-7-year-old seatting in the back. the front end of the nissan van was totally demolished and dropped to pavement, and the rear-end of my LS4 was totally crushed, but it crumpled so well, even the rear window was not broken and the LS was drivable. me and my son were totally fine with no long-term "side-effects". needless to say, I took the total-loss money and bought a 97 LS4. since your fiance got injured, don't settle anything with insurance before you talk to a personal injurey attorney first. wish her a speedy recovery!

saying what? dealer recommended you to put toyota Type 'T' ATF in power steering pump?! maybe they are confused too! 90~97 LS4 need Dexron II or III ATF as power steering fluid which is black-n-white stated in owner's manual. however, you never put Dexron ATF in LS4's tranny, and you SHOULD NOT put type 'T' ATF in LS4's power steering.

the thing really puzzling me is why folks still keep on spending big bucks on those European luxuries knowing they have been on the "least reliable" list year after year?! OMG, the entire line of mercedes are on it vs entire line of Lex cars are on the "most reliable" must be the "itch" thing...I am so glad that I am out of the mercedes' itches after owning 2 disastrous S-class few years back!

90~97 LS400: non-interference 98+ LS400: VVTi interference

you definately don't want to fool around inteference engine such VVTi. timing chain on my old Merc 420SEL that I used to own broke prematurely, it ended up costing me over $4k to get the valves job done and the chain replaced.

owner's manual clearily states ATF dex II or III for power steering in black and white. I don't understand why anyone want to take the risk to use anything else other than that. we've been thru the coolant business in great length couple of years ago in this forum. it's OK to use 'green' coolant that you can buy at corner gas station as long as: 1. completely 100% flush out the original 'red' coolant first. remeber more than 50% of the old coolant is trapped in the engine block, you must get them out, flush a whole system with water a few times over before adding new coolant 2. you must do 100% green coolant change say every 15K miles because they are not "long-life", and it can't never last as long as 50K like Toyota's red one. 3. if you ever decide to go back to 'red' coolant, again, 100% flush of the green coolant is a must. the additives are differnet in corner store 'green' coolant and long-life 'red' one, mix them will totally destroy all the protective properties of each other. also, when you do oil change at those 'chain' store (ie. jeffy lube, firetsone...etc), never have the shop to 'top off' any fuilds which often is part of so-called "25-point service". you just don't know what they actually use to "top off". it can be a disater if they put green coolant to top off the long-life red coolant you already have, or vice versa.

as I recalled, my mech just removed the CAM/crank pulleys (holding by a center bolt) to expose the bad seals, then just pried them out with screw driver. you don't usually remove CAM/crank pulleys themselves for a "typical" timing-belt job, but it definately worth the effort to go a bit further to change out those seals so that they won't come back to haunt you later on.

well, owner's manul calls for Dexron II or III ATF, and that ought to be the type you ever want to use.

I would not have 'jiffy lube' nor any chain store to do the flush job! I was about to have the tranny flushed for my SC400 at one local jiffy lube, but they wanted me sign some kind of legal waiver which held them no responsibility if seals were blown. apparently they've seen blown seal before caused by 'power flush'. needless to say, I skipped jiffy lube and had it done at dealer. $60~$100 for the whole flush job with fluid? I really doubt that the chain store will use genuine Toyota T-4 fluid which is not cheap by all means. just 16qt of t4 fluid alone can cost $100.

well, I did a complete 16qt+ tranny flush for my 96 SC400 w/170k about 6-month ago without ill effect. it was done at local dealer, costed me about $180 with fluid. I am not sure it was done by 'power flush' method or using the method Army described. normal tranny pan drain replaces only 2.5qt out of total volume of 16qt. it means most of the "dirty" fluid is still trapped inside the tranny. member 'lexls' has a tutorials of flushing tranny fluid beyond the normal pan drain: http://www.lexls.com/tutorials/transmission/transflush.html however, he referred the total volume was about 9qt. so, i'm bit confused whether it should be 16qt or 9qt. anyway, from dealer's invoice, I was charged with 16qt of tranny fuild @$7/qt (ouch!). from what I heard, "power flush" tranny on high-mileage car may have a high risk of blown seal. my 97 LS4 is approaching 120K, and due for the complete tranny flush. this time I will ask the dealer which method they use.

need to point out that the 1UZFE engine in 90~97 (Gen I/II) LS400 is non-interference type. started from 98, it became VVTi engine which is indeed interference type. if TB broke on a 98 or later model, you will have bent valves which is easily a $4K job to get them fixed up.