Cimburke23

I just did this myself on my wife's 00 rx300, the trannys ARE different, it is not a direct bolt-in like i had read on here. the driverside trans mount on the highlander is a post-type mount, as the lexus is the V-shaped mount. Also, you cannot just change the outer casings because the highlander has the vent hose connected to that outer casing. I had to take my old lexus outer casing, weld a boss of aluminum to it, then drill a vent hole into that boss so it would connect with the highlander vent hole. I took pictures, and will try to get them up on Wednesday when i get back to my garage.

picture of both transmissions, my original is the dirty one


picture of highlander transmission mount


picture of highlander trans vent hole, the bigger hole in the center of the pic


picture of my lexus trans w/o the vent hole


pictures of my custom extra boss weld puddle that i drilled the vent into

Lexmex

Which tranny, the U140E or the U140F?

Nad1370

What drivetrain do you have on your RX?
What kind of tranny did you get from the Highlander?

Highlander has 3 transmission options:
U140E<---6cyl 2WD
U140F<---4 and 6cyl 4WD
U241E<---4cyl 2WD

Rx300 only has 2 options:
U140E<--6cyl 2WD
U140F<--6cyl 4WD

You just might have gotten a wrong tranny for it.

Cimburke23

it is a 2000 RX300 AWD v6, i got a trans from a 2003 Highlander AWD v6, both trans are U140, i do not see an F on either trans but the one i received had the studs to put my transfer case on and everything. Also, the tranny i had in it before, and this new trans are doing the same thing, when it goes to shift into 3rd, it like misses the gear, then kicks in, only when accelerating slowly, i.e. shifting into 3rd under 30mph, but if it shifts into 3rd over 35-40mph, it shifts smooth like when we first bought the vehicle. any opinions on that? I have a friend who is a Lexus master tech and he says he has no clue, i even took him for a ride in it and he was stumped. lol, i guess this is just my kind of luck.

Cimburke23

anyone? posted pix now...

code58

CB- Was this the ONLY reason you changed the transmission? There are so many things that can affect the electronically controlled transmissions that we all drive today. Many vehicles have programming problems that can be cured with a reflash. (not saying that is your problem) I am amazed that a Lexus Master Tech had no idea what the problem might be. Have you done a search on shifting problems? Sure seems like I have read of similar problems on this forum or the other Lexus forum more than once.

Nad1370

I heard over at TN that 01-03 Rav-4(not sure where the cut-of is) had shifting issues as well.

The fix----> new ECM.
As Rog stated...it could be in the electronics.

Cimburke23

no, it had harsh downshifting as well, the trans had a ton of metal on the magnets in the pan, it needed to be changed anyway, but it started in the snow, i put it in neutral going down a hill, went to put it back in drive and it wouldnt go anywhere, cut it off, waited 5mins, started back up and it drove fine, which had me thinking electronics then also. guess i need to try a new comp. do these have separate trans comps or is it all one thing? does it need to be programmed to the vehicle or anything? i am used to doing honda work and they have the immobilizers in the ecu. thanks everyone.

Lexmex

No, they don't have a separate tranny comp and doesn't need reprogramming.

My recollection when we did the tranny work in 2007 back in Mexico was that we had to wait a good bit to get the tranny warmed up before we took it out and get the pressure going in the system. Even then we had a few issues we talked about here, in this old thread, https://www.clublexus.com/forums/rx-...went-bump.html

98dohc

I had a very similar problem. Original tranny went at 139K. Planetary gear came apart like most others. Had a full rebuild done. Now 12K miles latter it started slipping going into third only. It would slip for about 2-3 seconds before grabbing. When it would grab, it was like you where driving a manual and dumped the clutch. They pulled it apart and found the issue. They don't know how or why. But at the base of the small planetary gear, their is a bushing. It overheated and work its way out causing scarring on some type of drum gear that the planetary rest against. This caused a small hydraulic leak which would cause the slipping going into third. If it is continually driven like this, they said it is likely the planetary will fail. Also a note. The other bigger planetary that was also brand new was already showing signs of excessive wear. The pins for the sun gears were loose already. I've heard one method of preventing this is welding these so they don't wear out and this is one of the ways to make the planetary more durable besides using the needed updated planetary gears. (They are going to do this, this time around).

I'm actually currently looking for the thread with the part number for the updated planetary gear set. I don't think they used the new one on my rebuild 6 months ago. Anyone know of it?

Lexmex

I found this document a few weeks ago, but only applies to the FWD.

98dohc

Thanks. Yeah i have the FWD, so that is useful.

sktn77a

iTrader: (2)

So you had these transmission problems with the FWD RX300?

98dohc

Correct. It's a 2001.

Found out the other day that they did use the updated planetary. Hope the welding makes a big difference. Car should be back together today.

Dawish

I have my Lexus Rx300 year 2000.my ecu got damaged.so I replace it with Highlander ecu,program it .it starts without no misfire..but when I selecte drive the engine go off..dont know what wrong or if any ic or components dat I should put in there..any idea