I posted another thread here and got helpful info so I was hoping I can get help solving another issue I've been dealing with for a while\
I tried searching but to no avail for my specific car
anyways,

I have a 1998 LS400 with 240k miles running strong other than this.

When I put it in reverse I get no movement I have to rev it really high like 3500-4000 rpm to start getting some motion I know this is definitely bad for the car. Its slipping and has no CEL

the odd thing is when the car is cold in the morning on a cold start I can throw it in reverse and start moving just fine but once its warm it does not want to work

I had received a code for a transmission shift solenoid before but it has gone away and not come back

has anyone dealt with this before? its pretty annoying and i'm hoping it can be easily fixed.

 

proper fluids, proper operating levels? if the solenoid isn't giving you a cel light, then it just might be the clutch pack is really worn out, necessitating a transmission rebuild. my theory is this: oftentimes, the car's first thing to do when starting up, is to go into reverse, because often, cars are parked nose into their parking space. even more, if the car is still cold, and the engine is still revving in its warmup phase, the additional load caused by throwing into reverse at higher revs will cause more wear to this clutch pack. what i try to do is, let the car warm up, let the idle get to its warm normal speeds under 1k rpm, before backing up. i just hate the need to stand on my brake while i let the transmission SHOVE into gear, just to avoid the car backing up unwantedly. much nicer to have a warmed up transmission just slide into gear. less wear on the drivetrain all the way back to the axles, imho.

 

I remember your old post and I came to know that transmission oil change didn't work for u. Now what you can do is to remove the transmission pan and unbolt the shift solenoid and clean it thoroughly and bench test it to make sure it clicks, some times these solenoids get clogged and after cleaning, it will work again. Otherwise you have to change shift solenoid. Aftermarket solenoids are cheap. I am going to upload PDF files, check page number 1506. The first diagram will help you find the shift solenoid.
Changing solenoid is very easy. This PDF will help you on how to do it yourself.

 

Watch this video. You can see how solenoids get dirty and will affect shifting.

 

I'm gonna be tackling this project this weekend I want to thank both of you for these informative responses it seems like this is the problem im having