A New "Another Transmission Thread" Thread

[BillyJackJimBob]

Long time owner of my 2006 V6 with 240,000m on the clock. Truck has been ultra reliable with very little maintenance. Other than oil, fluids, and oddly enough, brake calipers (all four along the way), a wheel bearing and hub replacement, serpentine belt and an idler, and spark plugs at... 225k.... she's been gas and go.

This past summer I started noticing that if I stopped hard (not emergency stopping just hard) the truck would stall out or almost stall out and the rev the engine as if to compensate. Took her to my local mechanic and he found an o-ring was missing somewhere in the transmission as he was replacing the fluid. His guess was that was allowing air to infiltrate into the fluid and cause the issue. He also greased the drive line components really well.

When I got her back she was driving great. Even picked up 1.5 mpg on my fuel average. Happy happy! Fast forward six months and I've been having a new issue. I'll describe it as best as I can.

1. On cold starts she shifts later. Holding second and third gears much longer regardless of throttle input. Barely and throttle or wide open. It will eventually shift and the shifts are smooth. And seems like after a few miles the issue subsides.

2. When making turns at speed at an intersection (like slowing from 50mph to say 20) once throttle is reapplied or even remaining constant through the turn the transmission downshifts a gear or two too many resulting in a high rev of the engine followed by a quick up shift. This occurs when load is reapplied to the transmission. Shifts are still smooth though.

3. The problem I was experiencing back in the summer has returned. Again if I stop hard I get the bump after completely stopped and a near or complete stall.

The transmission is still silky smooth through ups and downs once on the road 90+ percent off the time. I have experimented and find that if I drop it into neutral just as the truck is rolling to a stop everything works better.

I have scoured the forums. I read were folks have the stop bump issue. But I've not found anything similar to what I'm having with turning at intersections. Any ideas?

 

[Drcoffee]

I shit you not, replace the MAF with a new Denso part. The MAF controls the transmission shifting. If the air isnt metered correctly, tranny will not shift right and feel like its hanging in gear. Another possibility can be a weak battery. Have it load tested .

 

[Buckaroo]

Make sure the ATF level is correct - low fluid level can cause these issues as well.

 

[waypoint]

What fluid did he use, and did he do a full exchange or just the ~3.5 quarts in the pan?

You have two symptoms: delayed upshift, and stalling during stopping...shop manual diagnostics table says:

Shift point too high or too low

1. Shift solenoid valve (SLT) circuit *1
2. Speed sensor NT circuit *1
3. Speed sensor SP2 circuit *1
4. Throttle position sensor circuit *1
5. ATF temperature sensor circuit *1
6. Transfer L4 position switch circuit *1

Engine stalls when starting off or stopping

1. Shift solenoid valve (SLU) circuit *1
2. ECM

However, the shop manual assumes you're running specified fluid. If your guy installed anything other than Toyota WS spec or Valvoline MaxLife, that's your first corrective action. Find out exactly what brand and type of fluid he used.

edit: given the age and mileage, I'd disconnect the Throttle Position Sensor at the throttle body, inspect the pins for corrosion or gunk, clean with electronics cleaner spray and re-connect.

 

[BillyJackJimBob]

Update day one. Had the battery tested and no surprise, it had multiple dead cells. Tested 30% reserve at 100% and only 10.2 volts at cranking. It was 4.5 years old so... a new Die Hard was installed. Also, removed the MAF sensor and cleaned it with MAF cleaner.

She died on first attempt. Restarted and idled at only 500rpm. My buddy told me to expect this. That it should clear up after running a bit as it relearned. And it did. First test drive was uneventful. So I decided to drive a route that always results in the downshift issue.

As I approached the up hill, left turn, that is slightly off camber I set my speed a little faster than normal so as to require a modest braking that would then require the downshift. And just as before, seemed to shift two or more gears down. Guessing to second. Speed was around 25 mph and RPM was 3000 and up.

That's when it threw a check engine light (the first time ever in our 239,287 mile relationship) and killed the VSC and ABS system. Also, it would only shift up one more gear. 50mph was 3000 ish RPM. Drove it to O'REILLY'S, Advance, and Autozone....none of which are allowed to read codes for customers... Due to Covid-19.... Whatever????

After I restarted the truck the Check Engine light and VSC remained lit but the truck shifted through all gears. So, I am trying to put a positive spin on it all. I at least have a code to be read. Monday I will take it to my mechanic and see what information that provides.

 

[BillyJackJimBob]

As for the ATF used I am fairly confident Eddie would use only recommend fluids. He and I had a lengthy discussion about the transmission and he drove the truck for a week trying to diagnose the issue. He was never able to recreate what I was experiencing. He works on a lot of Toyotas. I'll be sure to ask him about that on Monday.

 

[Drcoffee]

The MAF is a wearing part. Cleaning wont help if its failing. The fact that cleaning altered the performance leads me to think a new one will help. Got any friends with another 4runner or fj that you can swap it out?

 

[BillyJackJimBob]

Update day 2. Code read.

 

[BillyJackJimBob]

P2714

Pressure control solenoid performance. Stuck off.

 

[BillyJackJimBob]

Update #2. After shopping around for transmission replacement my local dealer was only a couple $100 from the lowest quote and $5000 lower than AAMCO? (Guess there is a sucker born every minute but I ain't it) So I decided to go with my dealer. Toyota South in Richmond, KY.

Had the master mechanic do a ride along to recreate the issue (and we did several times). After the test drive he said if he was a betting man he'd bet his paycheck the fluid was low. I said, "I hope you're right."

Took her back to the shop where the put her on the lift and came to get me in about ten minutes. Right out of the gate they found the line to the transmission radiator were leaking. Significantly. The mechanic then said "I'm 95% sure now."

So they are cleaning it up to find exactly where the leak is and what all needs replacing to fix the leak. After that they will fill the fluid levels to the correct levels and see what that does for the issues. Cross your fingers!!

 

[waypoint]

Took her back to the shop where the put her on the lift and came to get me in about ten minutes. Right out of the gate they found the line to the transmission radiator were leaking. Significantly. The mechanic then said "I'm 95% sure now."

That's a good find. It's common for the twin steel trans cooler tubes that run along the lower radiator support to rust, mine failed last year and started a dribble. The welded-on brackets are U-shaped and point upward, trapping water and salt which leads to rust at the pipe welds. Easy fix replacing them.

 

[BillyJackJimBob]

I haven't driven it yet but mechanic says she's shifting like a new one. Had the front axles and boots replaced while they were at it. (Neglected to repair them for about.. 100k). LOL. I'll pick her up tomorrow and let you all know how it goes. Oh, he said it only had about 1 quart of fluid in the transmission.... Holds 6? Wow...

 

[firebirdguy]

I haven't driven it yet but mechanic says she's shifting like a new one. Had the front axles and boots replaced while they were at it. (Neglected to repair them for about.. 100k). LOL. I'll pick her up tomorrow and let you all know how it goes. Oh, he said it only had about 1 quart of fluid in the transmission.... Holds 6? Wow...

1qt in the trans? it wouldnt have operated, i think he meant only 1qt came out of the pan when there should be about 3.5, so it was 2.5 qts low. the trans takes about 13qts total.

hope it works out for you & good that you caught it before any serious damage or just let some shop install a new trans when it wasnt needed.

 

[AuSeeker]

I haven't driven it yet but mechanic says she's shifting like a new one. Had the front axles and boots replaced while they were at it. (Neglected to repair them for about.. 100k). LOL. I'll pick her up tomorrow and let you all know how it goes. Oh, he said it only had about 1 quart of fluid in the transmission.... Holds 6? Wow...

Glad to hear fixing the leak has solved your issue.

Just pulling the pan drain plug it will drain out 3.2 quarts, most say 3.5 quarts but the owner's manual say 3.2, if they removed all the fluid from the pan, valve body, torque converter and all the fluid passageways it would be around 12 quarts.

How did they determine it had only 1 quart of fluid left in the transmission?

If they only drain out 1 quart from the pan then it was only 2.2 to 2.5 quarts low.

Now if they had to put in around 11 quarts to get it to the proper level then yes it only had 1 quart in the transmission but I highly doubt that was the case because the transmission wouldn't have worked at all being that low on fluid, a transmission will start having shifting and slipping issues with it only being around 1 quart low and really be having major issues being any lower than that, so if you were indeed 2.2 quarts low that would definitely be having the issues you were having, if it was 3 or more quarts low it wouldn't even go into gear at all.

 

[4Runner4Runner4]

I haven't driven it yet but mechanic says she's shifting like a new one. Had the front axles and boots replaced while they were at it. (Neglected to repair them for about.. 100k). LOL. I'll pick her up tomorrow and let you all know how it goes. Oh, he said it only had about 1 quart of fluid in the transmission.... Holds 6? Wow...

So I just want to make sure that I’m understanding the big picture here.

The very first two replies said to replace your MAF sensor and to check your transmission fluid level. You did neither, and opted to entirely replace your transmission. And while doing so, now you have been told that the transmission fluid level was markedly low...

Well, I’m happy that your problem is solved...


Sent from my iPhone using Tapatalk

 

[waypoint]

The very first two replies said to replace your MAF sensor and to check your transmission fluid level. You did neither, and opted to entirely replace your transmission. And while doing so, now you have been told that the transmission fluid level was markedly low...

In his defense, he made it clear that he doesn't work on it himself. Just drives it and observes incorrect operation, then takes it to a mechanic.

 

[Tironeous]

Happy to hear you got this fixed and it wasn’t something major! I can confirm less than 3.5qts is what comes out of drain from pan.

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[firebirdguy]

So I just want to make sure that I’m understanding the big picture here.

The very first two replies said to replace your MAF sensor and to check your transmission fluid level. You did neither, and opted to entirely replace your transmission. And while doing so, now you have been told that the transmission fluid level was markedly low...

Well, I’m happy that your problem is solved...


Sent from my iPhone using Tapatalk

my understanding of his last update is that they did not replace the trans, they put it on a lift & found a leak & checked the fluid was low, which is what caused the problems. so it was low on fluid that caused teh problems & so far he hasnt reported back on how it drives with the correct fill level. trans wasnt changed from what i gathered.

& when i say 3.5qts i almost always put a "~" before it... which means roughly or about or estimated. ive seen 3-3.5 on pan drains & anywhere in between.

 

[BillyJackJimBob]

Final update. Sorry for the delay but I typed up a reply and then deleted it... It wasn't the tone I wanted to relay. It was more of a response to the criticisms of random posts. I love forums. I really do. If this were a Miata forum I would have had at least three "part out" replies by now. So I'll try to be positive.

Long story short, transmission performance is nearly perfect after correcting the leak and replacing the ATF.

As for the debate on the fluid amounts, I had misunderstood the service writer when he called. I was driving a Kenworth pulling a set of doubles in the snow, so I'll take the blame for getting it wrong. He mentioned 4.5 quarts and six quarts. So what I got out of it was it was 4.5 quarts low our of six. But actually it was 4.5 quarts low as they recovered about six from the transmission.

In response to the critics that want to say I asked for advice and then did non of the recommendations and went straight to a transmission swap I would say, I ran every opinion here through a good friend that is a former mechanic and now we both drive for UPS. He agreed with every possiblity mentioned here and then began elaborating about the how's and why's. His opinion carries more weight than strangers on forums.

He is the one who told me to clean the MAF sensor vs replacement. He also said it was virtually impossible to get an accurate reading of how much or little fluid was in these transmissions. That's it's more of a learned process that includes getting the system up to temperature and adding fluid and waiting for an overflow. Something I wasn't going to do. And he totally agree that a weak battery and low voltage in the system could cause all these behaviors too.

So I did what I could do. On the Sunday afternoon I had available. I appreciate the insight and suggestions everyone gave here. They all were solid ideas. But when none of the 15 minute fixes solved the problem I needed to know worst case scenario. I had a decision to make. Would I fix it or trade it. Knowing transmission problems can turn into rabbit holes I wanted my local shops to give me their worst. And to me that was a transmission swap. Of course, I was open to letting someone look at the vehicle before just swapping transmissions. And actually all but one shop insisted that they look at it before they would even order parts.

I hope that this thread and my experience might help others who have a similar situation. My faith in this T4R is strongly restored and now I have my sights set on 400k! She's actually driving better than she has in years.

 

[toyo]

How could you not see that over a QT of fluid had leaked out on the underside of the radiator area? Not trying be an ass but that would be pretty obvious.