Harpo

iTrader: (1)

2001 LS430, 111k miles. (Trans fluid has not been changed that I know of. I realize it needs it and have it on the schedule, but not sure this is related.)

Accelerating from a stop at normal in-town pace, trans shifts twice before you're even through the intersection. Not really too early, no bogging, but shifts are felt as minor hesitations.

If you step on it harder it shifts later, but still with a noticeable surge that sets you forward in your seat a tiny bit. No slippage, no over-rev, just a hesitation going from 1-2 and 2-3. Really brisk acceleration is fine, shifts quick, locks up instantly. D to R is instant, mileage is great at 23mpg.

I've reset the ECU by disconnecting the battery for an hour, very slight improvement after 30 miles.

Any ideas? Shift solenoids?

Thanks in advance.

Tom57

Before you do any further diagnosis, change the trans fluid > Type T-IV. Do the drain and fill method or have dealer do flush and fill. If you do drain and fill, try it one time, then drive. If still not right, do a second drain and fill. Drain and fill only removes about 20 - 25% (less than 3 qts.) of total ATF capacity. Only after a reasonable ATF drain and fill would I look into other causes, if this doesn't solve the issue. You should notice a difference after one drain and fill.

ancdmd

It's premature to speculate on solenoids or any other source of the issue until after you've changed the trans fluid. Most likely any issue you're having will be rectified with fresh fluid.

Harpo

iTrader: (1)

I think I'll have the Toyota dealer do the fluid change, I'm not comfortable with the "run the tranny dry" technique I'm finding in the FAQ!

What sort of price to expect?

Tom57

Call both Lexus and Toyota dealers. Some dealers offer a trans fluid special for like $229 - $239. The drain and fill does not require running the trans dry. Simply remove trans drain plug (like oil change), allow trans fluid in pan to drain out. Install drain plug. Refill fresh trans fluid through dipstick tube with same amount as removed. Check dipstick after running.

VBSchmidt

Yeah, definitely check with independent Toyota/Lexus/Scion shops and the dealerships. I just hit 98,000 miles and it needed and my Toyota dealership did a transmission flush for $180. An independent shop that I usually go to tried to charge me somewhere in the $300 range and Lexus quoted about $250. It really varies, so shop around. Actually Lexus did tell me that with the age of the car they would rather do a drain and fill because there would be a possibility that a flush could mess up the transmission. Even though it's 14 years old, it only have 98,000 miles so I did the flush and it's great. You can slightly feel the extra smoothness.

Harpo

iTrader: (1)

Update: Had the Toyota dealer do a trans flush, $185, shifts much better now!

Lavrishevo

iTrader: (1)

A lot of places call it a flush when really it is a drain and refill. The machines are very expensive and problematic. I kind of doubt it was a flush for $185. The fluid alone usually runs $20+ a quart. Flushing the entire system uses a lot of fluid. We're talking like 10 - 20 quarts depending on the car. Anyway, glad it's doing better. Have the differential serviced if you have not as well.

Harpo

iTrader: (1)

It was an actual flush, using a Wynn's machine. And after reading some more posts here I'm not sure it was such a good idea, but I seem to have gotten by with it. Shifting is definitely improved, I hope it stays that way!

98SNAKETR

Not a fan of machine flushes

The added pressure has been known to lodge debris into tight passages

Not to mention contamination from older machines

A simple drain and fill done repeatedly over time is your best bet