colsoop Posted March 26, 2007 Share Posted March 26, 2007 So does anyone have an idea of a likely fix to this problem ? Link to comment Share on other sites More sharing options...
Tom Posted March 26, 2007 Share Posted March 26, 2007 Well there's gonna be a lot of written off supra's by 2008 if this is the case! anyone with a 94+ can scavange Link to comment Share on other sites More sharing options...
colsoop Posted March 26, 2007 Share Posted March 26, 2007 Well mine is a prime candidate for this issue to happen on i am a 93 TT 6 speed Link to comment Share on other sites More sharing options...
Tom Posted March 26, 2007 Share Posted March 26, 2007 tbh the thing i'm surpised at is that I havent heard of this from supraforums with their US spec supra's, and knowing the amount of miles they do you would think it's fairly common out there? Link to comment Share on other sites More sharing options...
Toy Motor Posted March 26, 2007 Share Posted March 26, 2007 To answer Ian and others, We had a target number of operational hours for each test mule. Of these operational hours, we worked out an average in real world conditions that each component or part of the vehicle would see X, Y or Z stress levels. We concentrated on the Z stress loading, Z being full operational load. Testing was done on the real road and non manned simulated testing was also completed on test 'rolling road' rigs which were fully motorised and servo'd to mimic driving over different surfaces, corners etc. Retro fitting a non LSD would alleviate the situation, yes. Extra welding was implemented to extend the floorpan and chassis life in this area beyond any warranty period and potential legal liability period - that being 12+ years. Further durability testing after the modifications put the lifespan to 15+ years which was more than expected, so quite a result, really. Any further welding in that area just moved the point of fatigue failure to a non-reinforced section. By increasing the size of the rails and mounting areas the issue could have been removed entirely, but if you recall, the design brief for the JZA-80 was to be as light as possible. So around 16kg was saved by simply increasing the weld thickness rather than the subframe mounting point size. Management figured that a 15 or so year lifespan was an acceptable tradeoff for keeping the weight down. Bob. p.s. I'm really really sorry to have brought this into the open Please forgive me! I think I'll just not talk about my time with Toyota anymore. Link to comment Share on other sites More sharing options...
RedM Posted March 26, 2007 Share Posted March 26, 2007 I don't like you no more. Link to comment Share on other sites More sharing options...
JustGav Posted March 26, 2007 Share Posted March 26, 2007 p.s. I'm really really sorry to have brought this into the open Please forgive me! I think I'll just not talk about my time with Toyota anymore. I wouldn't apologise, info like this is great to find out... means things can be looked at rather than someone randomly dropping a subframe on the road... Link to comment Share on other sites More sharing options...
AlanM Posted March 26, 2007 Share Posted March 26, 2007 Good that is being discussed Bob. I will still wait until Chris tells me to panic ,, lol Link to comment Share on other sites More sharing options...
colsoop Posted March 26, 2007 Share Posted March 26, 2007 p.s. I'm really really sorry to have brought this into the open Please forgive me! I think I'll just not talk about my time with Toyota anymore. Im glad you told me my car is due for pending doom in all seriousness its interesting to hear about these things, it doesn't bother me in the slightest that this issue can happen. One thing though put a warning at the top of your posts if you have any more cans to open about the shortcomings of the Supra Link to comment Share on other sites More sharing options...
Mike M Posted March 26, 2007 Share Posted March 26, 2007 Well mine is a prime candidate for this issue to happen on i am a 93 TT 6 speed LOL, you and and me both mate. Any cheap late 90's NA's for sale? (Large project pending) Link to comment Share on other sites More sharing options...
Faye Posted March 26, 2007 Share Posted March 26, 2007 That's really useful info -thanks Another reason to love my NA, but worry for Keiths UK Link to comment Share on other sites More sharing options...
SatSport Posted March 26, 2007 Share Posted March 26, 2007 Yes folks, one day your Supra will look like this......... http://img339.imageshack.us/img339/1632/halfcarsv3.gif Link to comment Share on other sites More sharing options...
Terminator Posted March 26, 2007 Share Posted March 26, 2007 I am really surprised that we have not heard of this before. As I understand it, this problem allegedly is more likely to be apparent on the JDM cars rather than European or US models. The figure of 15 years is suggested for a car operating at stock power levels. Accord to this new information significant increases in power would would accelerate the fatigue and significantly reduce the time scale in which the failure could occur. Our Japanese friends certainly like to up the power of their cars. Some came to this country with mods still in place others, were returned to stock, many of these had tell tale signs of modification if you knew where to look. Certainly a significant number would have brought potential failure into a time scale in single figures. Compared to stock cars, a number of imports have had a very hard life before being used on UK roads, therefore accelerating the suggested fatigue. Given the history of some of our cars there will be a signifiant number that have gone well past their sell by date. Yet as far as I am aware, not one single owner has reported any such failure. Given the serious horse power being achieved by US owners, I would have thought that we would have seen quite a few videos of this happening on drag strips in the states. Yet as far as I am aware there has been not one. I would have thought that 1500hp cars would be leaving there rear sub frames at the lights by now. Link to comment Share on other sites More sharing options...
Getrag Posted March 26, 2007 Share Posted March 26, 2007 How exactly is this accelerated testing done? And why 15 years instead of xxxxxx miles? Link to comment Share on other sites More sharing options...
dandan Posted March 27, 2007 Share Posted March 27, 2007 Interesting thread... Link to comment Share on other sites More sharing options...
AlanM Posted March 27, 2007 Share Posted March 27, 2007 As far as I am aware fatigue failure is a result of low load high frequency cycle, not high load. As already said this would correalate to mileage not time?? Link to comment Share on other sites More sharing options...
Supragal Posted March 27, 2007 Share Posted March 27, 2007 I was thinking the same as Termy, but maybe he's not saying that at 15 years the whole things falls apart, just that there is a slight possibility? Link to comment Share on other sites More sharing options...
Alex Posted March 27, 2007 Share Posted March 27, 2007 Wow can't wait for the back end of all these car's to drop off, I can then make a two headed car like James May! Link to comment Share on other sites More sharing options...
Chiefgroover Posted March 27, 2007 Share Posted March 27, 2007 I think this is all a bit OTT, too many highly tuned cars with big mileages in the USA still going strong. If you are concerned, get your legs seam welded, that ought to keep things together. Link to comment Share on other sites More sharing options...
lust2luv Posted March 27, 2007 Share Posted March 27, 2007 Is it just me, or does this sound like the biggest heap of bullshit I've ever heard? Can't believe everyone's taking this as gospel because some guy on the internet who claims he used to work for Toyota said so! It's on the internet, it must be true! If it's the act of driving the car that causes the wear and eventual failure, you can't possible quote the failure rate in years, only miles. You could do 20,000 miles in 15 years, or 400,000! What a coincidence they'll start failing after 15 years. Hmmm 1993 + 15 years = 2008. That's next year! This from a guy who claims to have driven 1 million miles in a mkiv. That's 8 hours a day at 100mph, 5 days a week for 5 years! Oh, and he's mentioned Soarer's already... To misquote Aliens, "did IQs suddenly drop around here?" Or is this leading up to April 1st? p.s. I'm off to rip my LSD out... Link to comment Share on other sites More sharing options...
Terminator Posted March 27, 2007 Share Posted March 27, 2007 Just reversed out of the garage over a pile of bull shit, and you wont believe it, the bloody rear subframe drop off. Link to comment Share on other sites More sharing options...
SUPRASUZUKI Posted March 27, 2007 Share Posted March 27, 2007 Only another year or so and we'll know whether these predictions are right or wrong I guess. Imagine the resale values if it's true!! Link to comment Share on other sites More sharing options...
Gaz6002 Posted March 27, 2007 Share Posted March 27, 2007 Is it just me, or does this sound like the biggest heap of bullshit I've ever heard? Can't believe everyone's taking this as gospel because some guy on the internet who claims he used to work for Toyota said so! It's on the internet, it must be true! If it's the act of driving the car that causes the wear and eventual failure, you can't possible quote the failure rate in years, only miles. You could do 20,000 miles in 15 years, or 400,000! What a coincidence they'll start failing after 15 years. Hmmm 1993 + 15 years = 2008. That's next year! This from a guy who claims to have driven 1 million miles in a mkiv. That's 8 hours a day at 100mph, 5 days a week for 5 years! Oh, and he's mentioned Soarer's already... To misquote Aliens, "did IQs suddenly drop around here?" Or is this leading up to April 1st? p.s. I'm off to rip my LSD out... Good point, it does seem strange. After all the effort Mawby put into the "hacking" of the site last year it does make you think! Maybe some more known faults will spring up in the next few days. Link to comment Share on other sites More sharing options...
Kranz Posted March 27, 2007 Share Posted March 27, 2007 Is it just me, or does this sound like the biggest heap of bullshit I've ever heard? Can't believe everyone's taking this as gospel because some guy on the internet who claims he used to work for Toyota said so! It's on the internet, it must be true! If it's the act of driving the car that causes the wear and eventual failure, you can't possible quote the failure rate in years, only miles. You could do 20,000 miles in 15 years, or 400,000! What a coincidence they'll start failing after 15 years. Hmmm 1993 + 15 years = 2008. That's next year! This from a guy who claims to have driven 1 million miles in a mkiv. That's 8 hours a day at 100mph, 5 days a week for 5 years! Oh, and he's mentioned Soarer's already... To misquote Aliens, "did IQs suddenly drop around here?" Or is this leading up to April 1st? p.s. I'm off to rip my LSD out... No, the man is talking sense. As an ex-employee of a major manufacturer & having worked on the durability side of testing I can say that what he is saying is very plausible & I for one believe him. But what I'm not sure about is this 15 years thing. Mule (development) vehicles are biult in various levels, from application prototypes (hand built & cobbled together) to conformation prototypes (off first tooling or prototype tooling) and finally production prototypes (off the production tooling before production starts). I have seen many mule vehicles enconter problems that did not actually occur in the final production vehicles, for all kind of reasons. Also test methods for accelerated durability are carried out at proving grounds where driving conditions are 'simulated' i.e for body & suspension durability the cars are driven all day over set courses that include a section or badly pot holed road, rough cobbles, step sections on both sides and kerbs. They are driven at a set speed over this course continually for a set number of hours (cycles) until they pass the required number of cycles, or until something fails. Components (or entire vehicles or part of vehicle) are also tested on huge 4 poster test rigs where the body attached to the bed plate and massive hydraulic rams pound at the suspension day & night. Once the fleet of vehicles and component tests all pass the required number of hours/cycles or whatever then that aspect of the vehicle is signed off for production. Any compromises have to be justified by the engineering team and approved by management (who don't like paying more $ for anything more than they have to). These tests are calculated from real world failures, and every model of car built that passes these tests is then monitored out in the real world for in service failures. If there are more than the 'acceptable' number of failures then the standard of the tests is increased..... so they should account for all in service use. But the opposite isn't always true. i.e. if a failure is seen during these tests and the final production vehicle design changed and then re-tested to ensure that it passes this 'abuse' testing, it doesn't necessarily mean that it would have failed in the real world in the first place!!! So, althought the testing would indicate that there is a 15 year lifespan of the rear subframe shell mounting points, these may not actually materialise. I'd suggest a wait and see approach, and some method of inspecting the failure area for signs of fatigue an immenent or future failure? Link to comment Share on other sites More sharing options...
Guest Terry S Posted March 27, 2007 Share Posted March 27, 2007 I think the yanks may have found out by now if it was a serious problem Stock rear end with TRD Diff Link to comment Share on other sites More sharing options...
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