Any records of a trans fluid drain-fill? If not I'd do One and then another every 5 motor oil changes - can make a huge difference on shifting - Luck

 

I just did a filter change, cleaned the pan & magnets, and flushed out the old fluid. The fluid looked worn, but no obvious signs of major damage or weird smells.

 

Then its part of the vehicle's warm up process - the late shift-higher RPMs are meant to warm up engine faster. My 01 4runner does the same thing Only when fully cold to about 140 engine coolant temp. Luck

 

Our '08 significantly delays the 1 - 2 shift when cold. It has done that for a long time. The last time I had the fluid changed, it did seem to improve some. We're due for service again. Hoping to get 300k out of the car. We're at 240k now.

 

Thanks everyone!

I typically only apply light to moderate throttle when driving anyway so I'm wondering if that has something to do with it as well (more throttle, more fluid pressure?). I went down the U660E rabbit hole and was reading stories of flaring on shifting, harsh shifting, etc. Yes, mine does does occasionally flare before fully warmed up, but seems to shift OK once everything is up to temp.

And I did follow the procedure to properly set the fluid level.

 

I think you're right about the throttle (less = less pressure in the trans).

 

That's what I'm thinking too. There's no slipping, lurching, or banging into gears; just some flare and harsher shifting when it's not fully warmed up.

I'm used to how Nissan and their JATCO's shift (NON CVT), and they tend to have a harsh 1-2 shift (no matter the vehicle) and upshift as fast as possible to lock up the TC and save gas.

For now, no codes so I'll monitor it to see what happens.

 

Believe it or not, I've had contaminated MAF and PCV cause shifting concerns on my 5-speed. A contaminated MAF will feed the ECM faulty data which is used for transmission shifting. A bad PCV caused fluctuations in engine vacuum when let off the gas so that the TCC clutch would intermittently lock-up causing a shudder, as well as fluctuating transmission line pressures as you mentioned. MAF cleaner and a new PCV valve would be a cheap way to rule out a couple causes.

Shifting concerns due to the transmission are generally first caused by debris in fluid causing wear to the valve body & solenoids. Abrasion wears down the valve walls, causing line pressure abnormalities. A reconditioned valve body can solve these problems before it causes major clutch wear. With these transmissions though, it happens over a long time if maintained. If the problem worsens, consider a reconditioned valve body using Sonnax upgraded parts. You might also want to put an inline filter in the cooler line so that debris does not accumulate and wear the valve body.

 

Hey everyone. Thought I would give an update.

When I did my transmission fluid change, I used Valvoline Maxlife and did flush out all the old fluid (using the DIY method of disconnecting the return line and running the car) and set the fluid level as best I could.

Still having the flaring when cold, but then it would randomly flare when the car was warmed up. For an entire week it NEVER flared ever, then the next week it was like it went a bit psycho.

I took it to my local shop who could not duplicate the problem (figures), but I did have them reset the adaptives in the TCU. Well.....no more flaring after fully warmed up, but she'll still flare a bit while the car is "cold" and under light throttle AND light load. Light throttle + going up a hill (with load) = no flare. I plan to double check the fluid level next just to be sure it's right, but I think ima leave it at that. Honestly, tearing open a transmission may create more problems than it solves for now and I want to exhaust all other possible options.

Does anyone know if a TSB software update exists for the early build date 2008 Avalons (One does for the 07 Camry V6)?

I'll keep you posted.

 

Does anyone know if a TSB software update exists for the early build date 2008 Avalons (One does for the 07 Camry V6)?

There actually could be, since there were updates to address shifting concerns with the U151E 5-speed on pre-2008 models. You might want to call a local Toyota dealer and ask them how much it would be to flash updated firmware, if available.

 

I was going to, but I think the dealer would want to charge at least one hour's worth of flat rate just to plug the car into TIS techstream. Once I receive my J2345 (or whatever it is) cable, I was planning to purchase a two-day license ($70) for techstream and check myself. That.....and I absolutely HATE going to the dealership for anything except parts.

 

I wouldn't try with a cheap cable. My Aliexpress Techstream cable isn't capable of resetting the transmission memory, for example. I think the connection is somewhat unreliable.

 

Hey everyone. Another update.

After researching a bit more, flaring when cold (mainly) could be a symptom of low fluid level. I tried to set the fluid level correctly when I flushed it but I was using an infrared thermometer on the pan and the front end was lifted to be level with the rear (at least by eye balling it). So I decided what the heck....let's add a couple glugs of fluid. Repositioned the car real fast after sitting over night and then raised it up, removed the plastic shield, setup my funnel and added a couple plugs (maybe 6 oz??). At this point, the car is still cold soaked and I did a few other things while raised up. After about 1.5 hours of sitting I started it up and went for a drive.

First impression.... much smoother engaging into drive and reverse when the car is cold. And after pulling out of my driveway and lightly accelerating....no flipping flare at all. Not one time from cold start to when I came back after driving around for 20 minutes with no a.c. on. If anything, I see a small rise in rpms when shifting, but my frontier does the same thing.... calling that normal.

Obviously, one day isn't definitive but it's a good sign I think. I'll report back after commuting this week.

Thanks every for all the help!

 

I am (hopefully was) experiencing a 2-3 flare that used to only happen during winter while warming up and has started happening year round now, sometimes even when warmed up. I tried doing a memory reset in techstream, found my cheap obd to usb cable that I use techstream with caused it to tell me that my vehicle didn’t support that when trying to run the reset utility. Upon driving the car though it definitely was reset as it shifted terribly for the first few miles. Shifting has improved though and no flares yet.
Originally I was planning to do another 2-3 drain and fills 50k miles from the last 5 at 100k miles, I’m at 140k right now and might just do it now. I used an ir thermometer on the pan to measure temp when setting the fluid level back then as I didn’t have techstream, so perhaps doing it this time with tech stream will help. There is a shift improvement kit from Transgo I think it was but installation was pretty intense, taking the valve body out and apart, etc. Would rather not do that if I don’t have to.

 

I would try to use techstream to determine the fluid temperature when you're setting the fluid level. Based on my experience, this transmission is VERY picky about fluid levels; you should see the TSB Toyota sent out on how techs should check fluid level...it's legit like 30 pages.

For me, I'm holding off as long as possible before I do any sort of transmission surgery. I can live with some flaring every now and then and my goal with this car is to mainly use it for commuting to work and to keep it around five years; I think I can swing that. I'm fortunate enough to have another vehicle that's newer with lower miles, so I have a good backup.

Good to hear resetting the adaptives helped your shifting. I would reset them after every fluid change you do too.

 

Update: Definite improvement after adding two "glugs" of fluid. When cold, engaging into drive and reverse and much smoother now and it shifts smoother while cold as well. I do still get a couple of flares (mainly 2-3), but it's nowhere near as bad as before and once warmed up it drives very nicely.

Do you guys think I should add a little more fluid and maybe reset the adaptives again or call it good and stop fiddling?

 

You seems happier now. Leave well enough alone. 🙂

 

I used Valvoline after reading tons of posts saying it gives same performance as Toyota WS. It did just for the first few days. So most likely I will return to Toyota WS on the next service.

 

I don't think it's leaking b/c everytime I'm under the car it's bone dry. I think I under filled a bit when I did my fliud change/flush.

I don't think it's leaking b/c everytime I'm under the car it's bone dry. I think I under filled a bit when I did my fliud change/flush.

What is your definition of "a bit?'

 

Oh I don't know....hard to tell....maybe 6oz? When I was setting the fluid level, I tried my best to level the car vertically, but I may have been slightly off level horizontally as my driveway does slope down and then away from the house. If the car was tilted down towards the driver's side slightly when I was filling, then I may have let more fluid out by accident.

 

Good day everyone.

Yes, I know this thread is approaching one year, but I wanted to provide an update on my mission to correct the weird transmission shifting/flare. All winter (and during cooler temps), it shifted and acted just fine with no flares or irregular shifting, however, as soon as the outside temps started to rise a bit (60-70F), it started to occasionally flare on the 4-5 change after the fluid was warmed up. After that occurred, I was pretty convinced the transmission mechanically is fine, but I'm dealing with a software or non-fully compatible fluid problem. Researched and ordered some WS compatible Idemitsu ATF and also ordered a J2534 pass-thru device from TopDon (confirmed will work with a valid license of techstream) so I could perform a "Learning Value Reset/Clear Adaptives" on the transmission after the fluid flush I performed myself.

Supplies arrived and I set out on a Saturday to get it all done; flush, fluid level set using a data PID from techstream, and performing a Learning Value Reset/Clear Adaptives. Negative on techstream as my laptop is too old and too slow to run techstream. HOWEVER, I was able to research my VIN within Techstream and could view all outstanding TSB's, applied TSB's, recalls, etc. within the Toyota database. Guess what....I found TSB-0050-09 - TCM Calibration: Enhancement to Shifting Performance & Smoothness that had NOT been applied to my car. This TSB applies to 2008-2009 Avalons before the following VIN: 4T1BK36B#9U331933 and specifically mentions shift flare, harsh downshift on reacceleration, and "jerk" feeling on reacceleration.

Fast forward to this past Saturday (with a more powerful laptop), and I set out once again; fluid flush, level set using ATF temp from techstream data PID, clear adaptives, AND apply the TSB. After about 5 hours of work and reprogramming, etc., I went for a drive to allow the TCM to re-learn after the re-calibration. At first....you could tell it wasn't too happy, but the more I drove, the better and better it shifted. The 4-5 flare appears to be gone, upshifts occur sooner, downshifts are smoother, and overall driving experience is MUCH improved - I'm way happier with the car now.

My advice and if you're having this issue, change/flush your fluid using genuine Toyota WS or Idemitsu ATF, set fluid level correctly (or slightly overfill like I did...it won't hurt and it's better than underfilling), and see if your car is eligible for the TSB. Techstream/GTS+ will NOT allow you to update your car unless you fall into the VIN range mentioned above.

I hope this helps some folks and I'll report back as things progress.

 

Wow! Thanks for coming back with update/solution!!

 

Welcome!

I was determined to do all I could myself before condemning a transmission that would only occasionally act up; it just didn't seem right to me.

I know these vehicles are older now, but there's still a lot of good ones on the road and I hope this information helps some folks out.

Moral of this story:

• Use Toyota WS or Idemitsu equivalent (Valvoline Maxlife might be ok, but for me it didn't help)
• Set the fluid level correctly using the correct procedure as prescribed by Toyota along with a legitimate scan tool (generic or Techsteam) to see actual fluid temp.
• Check for any TSB updates in Techstream for your vehicle - you might just be surprised

 

it's interesting, for me it's the other way around, I switched to Maxlife synthetic and it's buttery smooth. I can't even tell when it's shifting except when looking at the rpm. I tried OEM and wasn't impressed, not going back to Toyota WS outdated convention oil.

 

That is interesting. Makes me wonder if the software update really fixed all the issues, but I'm with you on Toyota WS; there's better alternatives.

I don't think I'd call these U660E transmissions Toyota/Aisin's best work....could be way worse (see Honda's 3.0 J series V6 auto debacle when it first came out), but could also be way better.

 

Remember to reset your shift adaptations if possible after changing fluid. I did a Maxlife drain and fill 5 times in 2020 and was getting nearly clean fluid out the drain on the 5th, still had the shift flare from 2-3 when cold out and cold transmission that eventually started happening when warmer out (completely gone after warmup always). In 2024 I did another couple drain and fills 50k miles later as maintenance and still had the random cold 2-3 flare (was summer so would assume it was pretty consistent still if it was cold ambient), decided to reset shift adaptations just to see what would happen and it was completely gone after a few days of goofy shifting while relearning. So it almost seems relearning is necessary after a fluid change especially to another type of fluid, and in 4 years/50k miles the transmission did not "adapt" on it's own apparently.

 

100% agreed with resetting adaptives after a fluid change or flush. The TCU will not learn on its own after changing fluid.