Automatic transmission

[ColinBarber]

12 hours ago, nicnac said:

On the SC I also dropped the sump and replaced the pan filter and cleaned the magnetic plates. at 52K ............... If you saw the oil and the magnets .......... in person ............you ALL might take my advice ...................... but its up to yourselves ...mine is good for another 50 k !!!

Have you replaced your radiator? Certainly worth doing at least every 10 years to minimum the risk of the transmission cooler failing and allowing coolant into the transmission, completely destroying the transmission.

I see this as a bigger risk than the transmission fluid if you had to do just one - but obviously worth doing both.

Certainly more transmission problems reported on these forums are due to a radiator failure than lack of maintenance on the ATF.

[nicnac]

37 minutes ago, ColinBarber said:

Have you replaced your radiator? Certainly worth doing at least every 10 years to minimum the risk of the transmission cooler failing and allowing coolant into the transmission, completely destroying the transmission.

I see this as a bigger risk than the transmission fluid if you had to do just one - but obviously worth doing both.

Certainly more transmission problems reported on these forums are due to a radiator failure than lack of maintenance on the ATF.

The radiator leaking into the transmission oil cooler to my knowledge is normally on the pre facelift radiators  pre Oct 2005 in the case of the SC . I had a look at it when I did the Cam belt / idlers /pullies /tensioner / water pump at 52 K after I bought the car . It all looks good including the plastic on the manifld to rubber pipes . If I had a high mileage earlier model I would go for the seperate transmission cooler that you can buy to completely separate the two systems . Seems to also be a problem in earlier LS GS with the earlier radiator . 

As regards the Transmission oil itself .... I have given up trying to persuade  non technical experts on here as to the wisdom of doing this item . Its up to everyone to make up their own minds . I merely point out that as a qualified engineer with 50 years experience who has actually tackled such transmissions and others that I have come to the servicing conclusions for mentioned . I can do no more . Sure you can buy a car and do exactly what the handbook says . The manufacturer wants the car to last the warranty period and are not interested in 100K plus cars .......... I on the other hand like everthing to be as good as you can make it !

Its not vogue in todays throw away world to think this way and I realise I am a dinosaur in terms of age , but at approaching 70 I still can turn my hand to any technical task either mechanically or Electronically ............ hows that for blowing my own trumpet !

In conclusion Derek asked for advice . I have given it as I see it .................. he will know what he wants to do . !! End off !

[Mr Vlad]

I have to correct a My Bad. I mentioned about the Mondeo ecoboost having the aisin gearbox. Wrong. It was actually in the 2.2 diesel. I had such a car and when I enquired about a gearbox oil change Ford stated it was a sealed for life box and no service schedule on it. I insisted they do one as I couldn't believe a gearbox never needs an oil change. They eventually did do one but I think they only did a partial drain and refill. Anyway sorry for my previous duff Info. I blame being braindead after being on furlough too long.

But as I've mentioned. I had a partial drain and refill on my car with its mileage at 78k miles. Now did I notice a difference after that drain and refill? Yes and for the better. That's why I'll be having it done yearly as my journeys are very short (2 miles one way) and once a week a circuit of the M60. Short trips aren't good for engines/gearboxes it's a given. That's why I'm on a service plan and my car will be treated once a year. My choice. 

I have to say tho this thread has almost turned into a war off words. Not good.

[johnbiker7]

Hello all

It is not very often that I put the proverbial pen to paper, but ,after 54 years as a mechanical engineer, most of those years being involved in manufacturing machine maintenance. I have worked for some companies who would allow machines to run till they broke, and others who had P.P.M system (planned preventative maintenance). It was my experience that fewer unplanned breakdowns happened, if one did the right thing before the machine / gearbox/engine, expired in a cloud of smoke. So in my opinion it is best to do all we can to prevent unwanted breakdowns, and if that means, changing the transmission fluid on a regular basis go for it. Sealed for life, is very tenuous and quite ambiguous, especially when applied to a system with friction materials. As these clutch faces wear, because they will, the friction material will contaminate the fluid, and when one takes into consideration heat and shearing forces on the fluid/oil. To finally get off my soapbox I would say change it, and to practice what I preach I had mine done six months ago, as preventative maintenance.

[Linas.P]

I agree with this in principal, but can anyone point me out to the statistics of how many gearboxes were ruined here because ATF was not changed every 50k miles? 

I am not aware of one, perhaps they do not exist (yet). And indeed it is inevitable that eventually gearbox will fail without changing "life-time sealed" fluid. The only thing I can report is that my car was 192k miles and already in 3 accidents and written-off by the time it actually needed one. And I advised that to the new owner and he now has new gasket, fluid filter and 5L of ATF in his boot to address it.

I am not against changing it, but it is not as big issues (statistically) as some are making out... and to really ruin your transmission you need to ignore signs of issue for years before it really ruins your gearbox. 

And in the end - I think all contributions are valuable, even if we disagree with the opinion of the author, so no need to compare it with trumpster.

[Mihanicos]

If you log into lexustech.eu and look up the maintenance schedule of each model, you will see that all " sealed transmissions " have a recommended time/mileage for fluid replacement, depending on use.

An australian auto expert  John Cadogan,  states in one ofhis videos on Youtube that the automatic transmission fluid's properties deganerate by the amout of excess temperature above rated. If I remember correctly, he recommends a fluid change every about 30 000 miles. 

I saw in a lexus 450h 2015 manual that the transmission should be replaced every 45000 miles and that was a uk car.

Chris.

[2ddesign]

Hi

Had my Transmission oil changed at Lexus Cardiff on my  2007 SC430, as preventative maintenance, flushed 3 times, milage 98,500.  August last year!

Nicnac is right, it is important  preventative maintenance of your vehicle, manual only states inspect every 4 years/40,000 miles.  

[Mr Vlad]

jack. Did Cardiff do the flush 3 times off their own back as per a schedule or did you ask for it? What did they charge?

[steve2006]

I’ll try and lighten this debate a little given Nick’s experience in aircraft maintenance ( Boeing 737 for a D check anyone 😀).

Toyota and Hamilton as a joint project actually developed a version of the V8 engine used in the LS400 and other which was approved by the FAA, twin supercharged and  producing 360 BHP.

The test engine only accrued 35 flying hours so it may have not got an oil analysis as the project never really got off the ground...pun intended.

https://www.planeandpilotmag.com/article/crazy-and-not-so-crazy-automaker-forays-into-aviation/nggallery/image/hellcats/

[2ddesign]

Vlad

I had a really good chat with the lead Tech mechanic and we agreed a 3 flush method, based on Nick's posting on the SC forum.

I asked for photos to be sent as the work progressed.

It was a quite time in the workshop and as a regular customer of 20 years, with some other work of over hauling the brakes, it came in at under £200

 

[Mr Vlad]

Wow that's a great price for a 3x flush. Think I'll ask for similar after a chat at service time. 

[Alfalfa]

I flushed mine, the gearbox gear dovn earlier now, recomended.

[ColinBarber]

On 1/24/2021 at 7:38 AM, Mihanicos said:

If you log into lexustech.eu and look up the maintenance schedule of each model, you will see that all " sealed transmissions " have a recommended time/mileage for fluid replacement, depending on use.

Only for the severe conditions schedule when one of the following is met on a regular basis:

• Heavily loaded vehicle. (Example : Towing a trailer, using a camper, using a car top carrier, etc.)
• Extensive idling and / or low speed driving for a long distance such as police, professional / private use like taxi or door-to-door delivery use.
• Continuous high speed driving (80 % or more of maximum vehicle speed) for over 2 hours.

 There is no interval for the standard schedule which 90%+ of owners fall under.

 

 

[Linas.P]

26 minutes ago, ColinBarber said:

Only for the severe conditions schedule when one of the following is met on a regular basis:

• Heavily loaded vehicle. (Example : Towing a trailer, using a camper, using a car top carrier, etc.)
• Extensive idling and / or low speed driving for a long distance such as police, professional / private use like taxi or door-to-door delivery use.
• Continuous high speed driving (80 % or more of maximum vehicle speed) for over 2 hours.

 There is no interval for the standard schedule which 90%+ of owners fall under.

That makes much more sense... that said I now know why my gearbox fluid needs changing now. I did 2500 miles eurotrip twice, first time average speed was ~108MPH and second time 114MPH, meaning that there was excessive amount of time driving at 80%+ of maximum car speed. About 3 month after second trip was the first time I got solenoid error.

As such above is right on the money. However, I do not expect anyone in UK are doing either of the things in the list - IS250 is not the car for trailers, deliveries, police and there are no places where one could reach, never mind maintain 80%+ of speed for prolonged time. 

[nicnac]

52 minutes ago, ColinBarber said:

Only for the severe conditions schedule when one of the following is met on a regular basis:

• Heavily loaded vehicle. (Example : Towing a trailer, using a camper, using a car top carrier, etc.)
• Extensive idling and / or low speed driving for a long distance such as police, professional / private use like taxi or door-to-door delivery use.
• Continuous high speed driving (80 % or more of maximum vehicle speed) for over 2 hours.

 There is no interval for the standard schedule which 90%+ of owners fall under.

 

 

You put this up before Colin . Do you work for Toyota / Lexus ....LOL

[nicnac]

15 minutes ago, Linas.P said:

That makes much more sense... that said I now know why my gearbox fluid needs changing now. I did 2500 miles eurotrip twice, first time average speed was ~108MPH and second time 114MPH, meaning that there was excessive amount of time driving at 80%+ of maximum car speed. About 3 month after second trip was the first time I got solenoid error.

As such above is right on the money. However, I do not expect anyone in UK are doing either of the things in the list - IS250 is not the car for trailers, deliveries, police and there are no places where one could reach, never mind maintain 80%+ of speed for prolonged time. 

Ill not be buying a car from you then !!!..............LOL

[Linas.P]

As if its matters when the car is 192k miles... (more like 198k now). By the time current owner needs selling it, the car will be worth less than 5L of ATF anyway.

[nicnac]

6 minutes ago, nicnac said:

That makes much more sense... that said I now know why my gearbox fluid needs changing now. I did 2500 miles eurotrip twice, first time average speed was ~108MPH and second time 114MPH, meaning that there was excessive amount of time driving at 80%+ of maximum car speed. About 3 month after second trip was the first time I got solenoid error.

there you go !! ..............If you had of cycled your oil you wouldnt have got that error ............ 😊

[ColinBarber]

10 minutes ago, nicnac said:

You put this up before Colin . Do you work for Toyota / Lexus ....LOL

🙂 I'm just making sure information is factually correct. Lexus in the UK do not recommend a service interval for sealed transmissions unless the vehicle falls into a severe maintenance category.

Personally I'd go beyond what they recommend which I have stated previously, in the same way that I would recommend people periodically (every 1 or 2 years) re-grease their brake calliper sliding pins (if their vehicle has that type of brake design) to avoid them seizing. Lexus do not recommend this either but it is certainly worthwhile to avoid extra expense at some point.

[nicnac]

Just now, ColinBarber said:

🙂 I'm just making sure information is factually correct. Lexus in the UK do not recommend a service interval for sealed transmissions unless the vehicle falls into a severe maintenance category.

Personally I'd go beyond what they recommend which I have stated previously, in the same way that I would recommend people periodically (every 1 or 2 years) re-grease their brake calliper sliding pins (if their vehicle has that type of brake design) to avoid them seizing. Lexus do not recommend this either but it is certainly worthwhile to avoid extra expense at some point.

Well said! .....................its important to point out though to MEMBERS here that are not mechanically minded/qualified that the Lexus recommendations are really MINIMUM service intervals and items that are necessary in their opinion to meet warranty standards . 

Any competant engineer could draw up a much more comprehensive list of items to be regularly  checked/serviced as in your example of the brake slide pins . 

Thats why the forum is a platform  to enlighten and educate to best practice, instead of following the bare minimum and following the mantra of "not required by service schedule" . Then people can make an informed decision as to what to do or not to do !

[nicnac]

13 minutes ago, ColinBarber said:

Lexus in the UK do not recommend a service interval for sealed transmissions unless the vehicle falls into a severe maintenance category

I would love to have a debate with the Tech author who made this statement or the desk jockey who came up with it .................. If they want to contact me  I would be more than happy to discuss 

[Linas.P]

18 minutes ago, nicnac said:

there you go !! ..............If you had of cycled your oil you wouldnt have got that error ............ 😊

Error just indicates that fluid needs changing and it is fully cured by cycling the fluid - it is not like that has damaged the transmission. This is one of very few reason where official maintenance manual advises to cycle the fluid.

Don't forget that ATF fluid is not like oil in the engine - lubrication and cooling is not the only function it does. It could be argued that primary function is actually run the automatic transmission (hydraulic fluid). And even compared to manual transmission lubrication is not as critical for autos.

[nicnac]

Just now, Linas.P said:

Error just indicates that fluid needs changing and it is fully cured by cycling the fluid - it is not like that has damaged the transmission. This is one of very few reason where official maintenance manual advises to cycle the fluid.

Don't forget that ATF fluid is not like oil in the engine - lubrication and cooling is not the only function it does. It could be argued that primary function is actually run the automatic transmission (hydraulic fluid). And even compared to manual transmission lubrication is not as critical for autos.

Linas .

I know exactly what ATF type WS is,what it does and the multiple functions it performs  . 

If you have not already maybe a look at John Cadogans article / youtube video on the subject of transmission fluid would be of benefit .

PS: He is also a qualified engineer  and did that profession before becoming a journalist . 

[nicnac]

11 minutes ago, nicnac said:

And even compared to manual transmission lubrication is not as critical for autos.

I dont know where you are getting these ideas from . 

Transmission fluid is the hardest working fluid in cars . It has to stand the shear forces of the torque converter and lubricate like an oil  while letting the clutches dissipate the friction forces and transfer the resultant heat that is generated . IT IS A MIRACLE FLUID !!! and the chemists who designed it should be applauded . However like all things in engineering it has its limits . 

[Linas.P]

Yes I am sure you know that, but there is gap between what ATF does, what role it plays in automatic gearbox is and what you suggesting. Your suggested service period pretty much matches manual transmission service period, yet we can all agree that automatic transmission fluid  in sealed boxes can last longer.

As I have already said - if not replacing fluid frequently would be so detrimental to wear and reliability of the transmission, then we see a lot of IS250 AT with transmission issues, yet this is virtually unheard of.

I have no doubt of your engineering proves, but I would conclude that when engineering theory meets reality this is exactly what happens. Yes theoretically it is better to replace the fluid more often, but all factors considered and rate at which gearbox wears, cost of doing it and the lifetime mileage of the cars it becomes less relevant.

Sure if we take two million mile cars where one had ATF changed every 50k miles and another where it was done on average every 100-150k miles when solenoid warning came one... I have no doubt the first one would be in better shape. However, both cars would be worth next to nothing, yet first one would have costed 3 times more money to maintain. And at £200/300 per change this would exceed the value of the car many times over.