razali2k5

About half a year ago, during the winter, I noticed that my wife's RX had a delay in upshift when it was cold outside. Namely, when starting on a cold morning and going on the highway, cruising (not accelerating) at about 65 mph the RPM stayed around 4k and then after 30 seconds or so dropped (you could feel the change instead of being perfectly smooth) to below 3k. This behavior was consistent on cold mornings and only happened if going on highway.

I have known about potential transmission problems since I bought the car but had put off replacing the fluid. I immediately replaced the filter and the fluid (used Redline D4 ATF). However, doing so did not fix the 'problem'. Now that it is summer, it does not happen anymore but I am wondering if anyone else has experienced this on cold starts.

The car has about 130k miles on it. My mom's 2002 Toyota Camry (which has pretty much same transmission) with 65k miles has pretty much the same issue I described.

There are no transmission leaks. I also check fluid often and the level is always same. Even before the fluid change, the level was fine.

JAB

Why do you think this is a 'problem?' It is designed to do exactly what it is doing.

salimshah

Here we have a case where the driver has to adapt to machine and drive slow (below 3k rpm) till the engine and transmission reach optimum temp. Idling the engine to warm up does not count as the transmission does not warm up.

Salim

99rx

iTrader: (6)

This has been discussed lots, It is doing that so the engine is able to warm up more quickly. There is no problem. Just try not to jump on the interstate immediately after first drive.

AlexusAnja

Ahhh.. a virgin CL member looking for some advise.

As others have noted, it's designed to do this. Mine's been doing it since '01 when I got her and no problems yet. Just keep it to 55mph for about a mile or two and once that temp needle hits the 2nd hash... bloooop, the big drop.