neep help with ls400 shifting problem

anyone here ever had a problem with there car not shifting past 2nd gear? my 91 ls400 sometimes wont shift past 2nd gear even though i have it in the D (drive) setting. its like the computer thinks its on the 2 setting or even the L setting.  it works most of the time but sometimes it jus randomly wont shift past 2 and it revs soooper high. so i baiscally cant go on the free way or anyother place past 25mph when this happens. 
the trans isnt slippin. it catches fine, it jus that it wont go past 2nd gear sometimes.
anyone had this problem or know what it could be??
thanx a lot.

has the trans ever been service before like a simple trans fuild change and flushing? try doing that first and reverse flush the cooler to take out any crap in the lines. also if that dont work then check the electrical circuitry or connection to the shift solenoids. 

i havent gotten a transmission problem yet but i have heard of problems like yours. just keeping up  with the regular service and the trans will be fine.

i would have to say its the solenoids. maybe theres a loose connection going to them. or it could be that your trans fluid needs to be thourghly changed... dont go cheap on your trans fuild either. get some quality stuff. and get the trans filter replaced and all that too.

thanx guys for all ur replys. ima change out and flush my fluids today. ill see if the problem still occurs. also what trans fluid do u guys recomend?

Toyota or Lexus transmission fluid only, trust me on that.  Other fluids will mess up our transmissions, it's known (get it from Toyota it will be cheaper than at Lexus).

yeah the toyota stuff. do a drain and fill, it should be enough. run it about a week, then do another. buy 9 quarts, do it over the process of a month. takes 2.3 quarts per drain and fill. whole transmission holds 7 or 8 quarts.

[QUOTE=bodybdr247;69610]thanx guys for all ur replys. ima change out and flush my fluids today. ill see if the problem still occurs. also what trans fluid do u guys recomend?[/QUOTE]

on the trans dip stick it recomends toyota type 3 dextron trans fuild i believe. you could use toyota type 4 dextron fuild, its compatible with type 3.

if your transmission has never been flushed in the past I wouldn't recommend doing a flush now.  just drain and refill if anything.

thanx everyone! i jus came back from the store and bought royal purple. but now since reading all ur posts and replies ima return it and go to toyota and get the toyota trans fluid.
 
thanx again for the quick replies. =)