forplatina

Hi,

Sorry I'm french and I don't speak english very well...

So I have a new SC430 2002 with 140 000 km (87 000 miles) and I have a big problem with the transmission.

When I accelerate strong, and when i get about to 110 km/h (65-70 mph), the gear slipping and after the cars jerks, it kind of lunges forward for a moment.

When I drive slowly or normaly, no pbm.

The transmission fluid was changed completely and it's ok now.

The différential fluid is replaced too.

I read this post : https://www.clublexus.com/forums/sc4...x-problem.html it's for me the same problem.

But the autor don't tell slipping pbm. And today, I controlled engine mount by professionnel, and they're OK.

Finally, I don't have warning light and no faults code with ODB2/ECU.

The battery was changed.

Have you some Idea please ? You're more spécialist than in France..

Thanks.

lexixel

Hi,

This could indeed be a slipping clutch pack. The car lunges forward probably because it's trying to shift up (not too well).

Maybe you could check the fluid level when cold (immediately after starting the car) - is it at least at the lowest notch?

Also, the feeling of the lunges - is it the same as when you move the shifter from e.g. 2 to 3 or 3 to 4 when driving?

Coleroad

Your going to need to take it to a good transmission shop. We are just guessing if we give you advice. Torque converter going bad can give the same symptoms. Valve body issues, solenoid problems. Take it to the best independent transmission shop you can find. If you take it to the dealer odds are they are just going to want to replace it.

DshngDaryl

Bonjour et bienvenueAre you sure the motor mounts are ok? There have been other people that have a similar story and find out the mounts are bad.

https://www.clublexus.com/forums/sc4...x-problem.html

forplatina

Lexixel, I'll try to move the shifter and I'll come back for you say.

DashingDar, I rode this post. And I hoped it was the problem but the motor mounts were checked, and none is broken.

And normaly, if the motor mounts were broken, the car jerks would also when I do a kickdown.

Bgw70

You need to make sure they used the correct transmission fluid for your SC430.

i have read that in Europe they use the other Toyota Fluid and it is wrong.

see post 16 in the link you provided...did they use this fluid?
https://www.clublexus.com/forums/sc4...x-problem.html

forplatina

It's true. Toyota/lexus dealer in France use DEXRON III and not ATF Type IV.

I bought mobil 3309 today (same ATF type IV) and I'll change again the fluid.

Bgw70

Dexron III is not fine..check the owners manual.

Caflashbob

Steve at luxury motorcoaches the lux link guy mentioned that running the trans that long can block the internal solenoid.

a power flush normally fixed it according to him.

Crud in the solenoids.

had my fluid changed at 20k miles. Used to be the std chsnge interval until the World Series six speed came out.

he still reccomemds changing at 20k to avoid solenoid issues and a check engine light finally from it

forplatina

The (2002) owners manual say ATF type IV.
​​​​​​
Caflashbob : What is a power flush ? I don't understand this word (with Google translate...), sorry..

lexixel

That's really bad. Those *******s used WS in my 2003. I had to threaten them to get them use Type IV. But then I changed myself six times with 3309.

I think it's probably just the fluid & level.

They actually have Type IV (need to order), but they're too stupid and ignorant.

Good idea to buy an electric pump that sucks the fluid out from eBay. The aluminium pan is quite thin and very easy to strip. ****ing dealer wants ~600 euros to replace it.

lexixel

I think Dexron 3 is for the power steering?

Anyway I think these dealers seriously underfill the transmission. They supposedly use a thermometer gun at the pan to get the temperature to check the level - I just don't know if they're checking at the right temperature!

They only know those sealed transmissions (because nobody has more than five years experience).

I read somewhere that a Toyota engineer says to drive 10-15 kms in relatively empty road from cold. From feeling the shift quality, I think it's best to check at cold (10-20 C). If the level is at least at the cold mark, it's more or less OK.

If the fluid is between the hot marks after a long drive, the transmission is underfilled. At least in newer cars that can display transmission temperature, I see that it can take up to 30 min / 40 miles even in the summer for the transmission to reach operating temperature (200 F - yes, the old five speed probably has a lower operating temperature with T4).

forplatina

Yes dexron 3 is for power steering.

Do you know : http://www.lexus-tech.eu/ ? (go to "repairs menu" and repair manuals)

for 3 euros by hour, you can read all repair manual, procedure and tsb for all lexus model.

This is the european procedure to check the fluid transmission level for SC430 (5 gears) :




And fluil transmission reference (ATF TYPE IV) :

Jabberwock

2001-2005 SC430s have a 5 speed AT that is not sealed like the SC430 2006 and later 6 Speed ATs. The dipstick for the AT should have a mark for full when cold and hot, be sure fluid is up to full mark when car is cold (first thing in the AM after sitting all night).

If I had the problem you are describing with no error codes I'd first have AT fluid completely changed again this time using the exact AT fluid specified in your car's operator's manual. A complete fluid replacement should be about 11-12 quarts - it is not a basic AT drain and fill which only replaces about 3 quarts per drain and fill.

Did the problem you are having with the AT occur before you had the AT fluid changed, or only after the AT fluid was changed?

forplatina

I bought my car 5 days ago... So I don't know if the problem was before the fluid changed. Normaly the dealer has changed a lot of fluid (3-4 drains and fill). The fluid is very clear.

Lexixel, I bought this one : http://www.ebay.fr/itm/Pompe-electri...EAAOSwd2xXQcvG

You think it's ok ?