VigorousBrando

Hi,
The most probably cause is the o ring seal on the reservoir this is available from Lexus at around $6.00 Part # 90080-30040
You need to remove the low pressure return pipe and 3 bolts holding it to the pump. ( you don't have to remove the pump itself)
Remove as much fluid as you can 1st using a rubber bulb type chicken baster then put plenty of rags under the pump to catch any remaining fluid.

Here are some pictures showing the bolt locations and the o ring.

http://i39.photobuck...exuspspump1.jpg


http://i39.photobuck...exuspspump2.jpg

Reassemble then top up the ps fluid and bleed the system.

Good luck

Just wanted to thank you for this suggestion. I think it's going to solve the issues I'm beginning to have with my pump which was just replaced a couple years ago. The car leaks a small amount of fluid after it is turned off and left alone, and I suspect it is coming directly from the pump. The system does not "whine" while in use or act up, but i know P/S fluid bis leaking somewhere because the reservoir needs refilled routinely.

Hopefully an O-Ring is all I need, but are there any other things I should be looking for?

Hey everyone, another update.

My SC400 now has ~232k and it has been almost 4 years since we did the transmission flush. This original transmission Lexus thought was dying is still in the car! On a routine inspection today though I found the T4 ATF fluid needs to be replaced again. It's not red, rust brown, brown...it's black. My dad took a look at it and we've decided to do something about it this week. Looks like some of my college graduation money is going toward preventive maintenance on what has been a pretty good college car.

Results: Flushed 10 quarts OEM T-IV ATF through the entire system, 2 at a time. I thought it would still be somewhat black when we were all done, but the fluid now is still a clear red after driving it around a couple of weeks. Transmission shifts smoothly and I haven't had any problems with it so far.

So, for me at least, the full T-II to T-IV replacement we did back in '07 (all at once rather than 2 quarts at a time) has led to no repercussions. For all I know though, it may have originally had T-IV in it when I bought it...