92 Lexus LS 400 - Slipping Transmission

[yummy88]

My 92 LS 400 with 200K miles appears to have a slipping tranny. It is not at the stage where the rpm climb does not correlate with speed. But I can sense that it is slipping.

My question, what is the best way to get max life out of a possible dying tranny.

1)Change transmission fluid (it uses Type IV Toyota ATF) every 3K when I change oil (no problem as it takes 2 quarts and is really easy to change)
2)I guess keep rpm low? Someone told me high RPM,especially full throttle gear changes at high rpm kills the transmission.
3)Should I take it off overdrive when in the city (I do mostly city driving).

How about some AutoRx for the transmission?

I figure that if I keep my fluid clean and not push it, it might keep the temp down (just in case it is slipping) and the constant change of ATF fluid will replenish whatever is lost in the higher temperature operating env.

Any advice is appreciated.

 

[The Critic]

LS400's transmissions are bulletproof, but 200k is still a lot of miles and things don't last forever.

I would pull the pan, change the filter (especially the o-ring if there is one, since a deteriorated one may cause shift problems), and refill with new fluid for now.

 

[csaxon]

Type IV atf is not approved for your car and may cause damage according to TC003–98 dated June 19, 1998.

 

[biomed_eng_2000]

AutoRX your transmission. I just did my Lexus LX450, Acura Legend, and Toyota Sienna.

Of the above cars, only the Acura (208k total miles) was slipping a little at high rpm's. After the AutoRX treatment...NO MORE SLIPPING!! Yippie.

 

[unDummy]

Does that TSB include his year vehicle? Quoting it is meaningless with posting a copy of it.

If the vehicle is factory filled with T-IV, and T-IV is mentioned either in the owners manual or dipstick, how could it be wrong?

What I would do is drop the pan, clean it, replace the filter, button her back up, top her off with Valvoline Maxlife, and then completely flush with Maxlife.

No additive will make up for wear. But, new fluid will make up for sheared fluid. New filter will flow more then clogged filter. New ATF will condition the seals and clean too!

Drive gently. Keep OD off in the city(reduces number of shifts).

Prior to the flush, if you want to see if viscosity change would help(new fluid), throw in a bottle of Lucas transmission fix stuff. This will simple increase your visc and improve seal sealing. If Lucas helps, then a filter change and flush would be smart to do completely/correctly ASAP. If lucas fix doesn't help at all, make sure that there are no tuning/running problems. Tuneup parts, throttle speed rpm sensors, ground or wiring corrosion,.... can cause transmission issues.

I fixed one transmission problem with a fuel filter. Its amazing how components interact.