JKenya7

I just bought a 2003 Lexus ES300. Didn’t notice at first but trans shifts strange sometimes in a couple of gears. Seems to be a little slow shifting in 2nd or 3rd. Sometimes a slight bump when shifting. Upper dogbone engine mount was cracked so I changed it. Any suggestions?

LeX2K

How many miles? Your choices are do nothing, or drop the pan change the filter refresh the fluid.

JKenya7

Have you had this problem?

LeX2K

I've serviced cars that showed large improvement in shifting after a transmission service.

JKenya7

OK, thanks!

HydroDog

There is a pretty substantial difference in shifting using the Toyota type 4 fluid and any other multi brand fluid.
When I bought my 03 ES a couple months ago the PO just had the transmission serviced and refilled with Amsoil according to the receipt. Around town it was ok but freeway on-ramps was terrible.
So I changed it with Valvoline Max life. Still not very good shifting and if you ran it to redline it would try to lockup on 2-3rd shift.

Did a complete flush by draining the pan and refilled and removing the transmission lines off the radiator starting the engine and pumped the fluid out while pump new fluid in with a small electric HF pump. Took about 12 quarts.

Definitely shifts better than before when warm. Still a little sluggish when cold. It’s never tried to lockup again.

itspanda

My car would also have a hard time shifting into overdrive when its REALLY cold outside. Other than that its okay. Sometimes I'd scan the ECU while driving when the car starts lagging and it tells me its a knock sensor. I had a cracked engine mount, and whenever i'd hit a bump, i think the microphone would pick up that noise / vibration and retard my timing, and stop me from shifting into overdrive to prevent more damage to the engine. I fixed the engine mount and the shifting problem went away! BUT.. cold weather and it still takes a while to shift - only until the engine is warm

JKenya7

What kind of fluid did you use when you did the flush?

BROCKES300

​​​​​​+1 on this.

Switching to the Aisin type 4 from rockauto.com, or Toyota type 4 from dealer (I think it's the same)... Really made a huge difference in the shifting of my 2000 ES (325k) and my mother's 2002 ES (245k). When you do a flush it will introduce new detergents to an old transmission, which is covered in varnish. That's probably causing sticking solenoids, causing your shift pausing. The fluid may turn dark rather quickly. I would recommend another drain and fill after about 15k, or when the fluid gets darker. That way, less varnish and dirt is suspended in the fluid. Personally, I would continue drain and full every 30k.

Also, what ever you do, don't use that thick lucas additive. Or anything like it. I think that was made just for crappy American cars, as a last resort. It made my shifts worse.