The weather back here in NY is gloomy and chilly, and so I thought I’d give some feedback on my newly transmission flush service recommended by you since something like this puts a smile on my face.
The first thing I noticed after the transmission flush and/or fluid exchange service was increased HP ( horse power ). There are two sharp gears in my Lexus transmission that pull the car really hard. Before the flush, these two gears weren’t engaged as often when I hit the accelerator hard. But they do now, after the transmission service, these two gears make my car feel similar to taking off in a commercial plane.
Conversely, while entering the interstate highway an hour ago, I decided to play with the car’s HP strength by hitting the accelerator and in no time my speedometer reading was at 80mph.
It amazes me that a simple transmission service could do such wonder.
The next thing I noticed after the fluid exchange was incredible smooth shifting. I can barely feel the car changing now. The car feels new and exciting to drive.
I will perform this service again around 120,000 miles.
Just a question: what it is about front and rear differential fluid service I’m hearing about on the Lexus forum ? Is this brake fluid ? If no, do I need this service as well, or was this included in the transmission fluid exchange service, such as both being done at the same time ?
Thank you so much for helping care for my car.
Clueless.
The trans service definitely seems to have been a good idea. The trans fluid is sort of the life blood of the trans, so it makes sense a fluid freshening would produce an improvement. As to the explanation for the improvement , possibly some of the internal seals were starting to harden and begin to leak a little, preventing the full force from developing, needed to effect smooth gear shifts. Or perhaps a fluid path was partially obstructed and now clear. I doubt anything else was done. Can’t speak to your car, but none of my cars use brake fluid for the differentials. 70-90W hypoid gear oil is what is normally spec’d. The most important property for brake fluid is that it holds up well to high temperatures. For differentials, it is the amount of slippery-ness. Suggest to ask your dealership shop for further advice on the differentials. My truck has two, and the fluid seems to stay in good condition a really long time (10 years/100k miles) as long as it doesn’t get wet. If it gets wet it has to be changed immediately. I used to change my truck’s every day on camping trips that involved crossing deep streams.
No HP gain, the transmission is just working more efficiently and the transmission is back to shifting and down shifting (what you are feeling) like it used to… It is possible that they flashed the TCM with any updates… But NO increased engine HP…
Your A760H transmission has the AWD/transfer case unit bolted to the tail end of the transmission, it sends power (via 2 driveshafts) to the F&R diffs, if not serviced with the trans, it needs to be serviced, the F&R diffs (front and rear differentials) and they need to be serviced… Mr Nevada has the maintenance schedules for all the above, your owners manual will as well…
Then you have a completely separate braking system that contains brake fluid, that brake fluid needs to be exchanged also…
So you have a transmission, an AWD/transfer case, a F diff, a R diff and a braking system… They are 5 separate units that all work together in one way or another to propel and stop your IS300 AWD, and they all have their own fluids to be delt with…
I had the brake fluid exchanged at 42k miles by Toyota because they said the oil was dirty. The user manual suggests changing the brake fluid at 60,000 miles.
The user manual doesn’t say anything about F/R differential service, so this is why I’m asking here. I only stumbled upon this subject by reading comments on the Lexus forum.
You are right when you said the HP doesn’t increase after a flush. I should have worded my statement better. And yes, after the flush I’m feeling sharp response from the gears
Very true. It’s very noticeable. Even without hitting the accelerator too hard the car is ready to take off. It feels so good on the highway and makes passing another vehicle more sufficient, like there is no delay in performance after the flush.
No matter. The basic story stands - have the trans serviced regularly. As for the differential fluids. First see what the owner’s manual says about that. I’m curious. But, depending on the kind of driving you do, have trans and differential fluids serviced every 30-40K miles is not out of line.
Check your owners manual, usually brake fluid is service in years, not mileage. Generally three years. But I just have it done when I have pads/rotors replaced.
