High Mileage trans fluid change

[Pilot2]

Just bought a 2007 is250 with 155k miles. Transmission shifts very smoothly. I do not know if the fluid was previously changed. Having heard stories of problems developing with trans fluid changes in high mileage cars, is it likely safe to change?

[dibley22]

I understand your concern for sure ..Ihad a similar issue re my 2007 lexus gx 470 with 81000 miles which I have owned since new..my dealer did not want to do the job as they appear to not recommend it..Iwanted to do it because after 12 years my gut told me that the fluid has to have degraded or gotten pretty dirty..I took it to a well recommended shop ..they ordered the toyota fluid and did the change ..cost me 225.00 ..mechanic let me see pan once it was off the truck and old fluid draining ..no bits of metal or whatever at bottom of pan which is magnetic..3000 miles later no issues or problems all seems ok....Before  having the change done I called that radio show "THE CAR PRO" he said very clearly ..change the fluid but"BUT DO NOT FLUSH IT "..so I pass this info on to you ..I hope it helps. Pete

that kind of made me feel pretty unsure as what to do.. 

[Pilot2]

is250-transmision.pdfI had Blackstone Labs perform an analysis on the 155,000 mile WS transmission oil in my "new" 2007 is250; the results are below.  In short, the Toyota WS fluid, even after 155,000 miles, was still performing its job.  The "universal averages" that Blackstone has for this transmission was with 58,200 miles. when you compare those numbers to the 155,000 mile oil, the wear metals were approximately 3-times higher thus demonstrating that even if the WS transmission oil had been changed, the wear metals would have been about the same.  Impressive.

As the transmission appears to be operating/shifting perfectly and the WS oil analysis produced no "off the charts" wear metal analysis, I will go ahead and do multiple drain/fills to freshen the WS transmission fluid.       

is250-transmision.pdf

[JGrantIS350]

I've owned my 007 Lexus IS350 for just over three years now. I got it with 101K. Today is 06/14/2021. my car is in the shop as I type this post with 152,760 for a transmission pan drop and screen/filter replacment service. I was allowed to drop off all Lexus OEM parts needed to complete this service. I'm not having any issues with my transmission thus far! That I know of...

The car is far from stock I must say. there are several after market proforamance parts on this car. (Almost Track Ready)

Pan Gasket 3516860010

Filter/Strainer 3533050020

 Filter/Screen rubber O Ring 

1X.   9030131014

Crush washer X2 one for the drain and one for fill plug.

(WS) World standard 6X quarts 00289ATFWS

I was told by a highly known engine builder in NASCAR that the shop is highly recormended with Toyota/Lexus cars. To the best of my knowalge a service has never been done on this transmission.

I've also heard the horror stories behind doing a drain and fill at this milage.  I left the shop feeling i did the right thing.  Only time will tell. I surplied a small glass Jar to get a sample of the olf fluid.

Id like to see the PDF but it says its no longer available. 

Jeff Grant Mooresville NC USA

[dcfish]

I would drive with full confidence, Do it again after a few thousand miles and then compare both to new fluid, You'll be glad you did. I had a GS300 I dropped the 2 litres of tranny T4 every oil change, Yep, No issue ever after 225000 miles, I also installed a tranny inline cooler and filter with magnets. The fluid was always new. I loved that car.

[Cfauvel]

On 6/14/2021 at 2:03 PM, JGrantIS350 said:

I've owned my 007 Lexus IS350 for just over three years now. I got it with 101K. Today is 06/14/2021. my car is in the shop as I type this post with 152,760 for a transmission pan drop and screen/filter replacment service. I was allowed to drop off all Lexus OEM parts needed to complete this service. I'm not having any issues with my transmission thus far! That I know of...

The car is far from stock I must say. there are several after market proforamance parts on this car. (Almost Track Ready)

Pan Gasket 3516860010

Filter/Strainer 3533050020

 Filter/Screen rubber O Ring 

1X.   9030131014

Crush washer X2 one for the drain and one for fill plug.

(WS) World standard 6X quarts 00289ATFWS

I was told by a highly known engine builder in NASCAR that the shop is highly recormended with Toyota/Lexus cars. To the best of my knowalge a service has never been done on this transmission.

I've also heard the horror stories behind doing a drain and fill at this milage.  I left the shop feeling i did the right thing.  Only time will tell. I surplied a small glass Jar to get a sample of the olf fluid.

Id like to see the PDF but it says its no longer available. 

Jeff Grant Mooresville NC USA

Are the transmissions in the IS250 and IS350 the same? As in , are the parts listed the same for the IS250?

[Bykfixer]

Go to Lexus parts now and you can type in IS250 and look up the part number then type in IS350 and do same.