[PhantomCamOp]

***FIXED*** 04 Auto Transmission shifts to neutral when driving... and more!

This is my first post, so thanks in advance for everyone's patience and, hopefully, help!

My wife's 2004 V6 Camry is not happy. As you accelerate from a stop, the automatic transmission will go from first gear to second, and then sometimes just drop spontaneously into neutral. Because you are in the process of accelerating, the engine RPMs increase until you take your foot of the pedal. In the short trip to the dealership for testing, the problem seemed to reset itself when the car was fully stopped. Other times it just reengaged with the transmission on its own without stopping.

Each time the transmission disengages, another strange thing happens--the instrument panel goes bonkers. The speedometer needle drops to zero, but the tach keeps working. The ABS, check engine, and brake lights turn on.

The dealership had the car for several days and has only been able to scan codes indicating the ABS system and the rear wheel speed sensors. I'm skeptical--especially since the repair estimate is nearly $4,000! I'm taking the car to an independent shop tomorrow for a second opinion.

I can follow up with more details from the dealership's diagnostic report, but for now, all I can say is that the car has almost 100,000 miles and we haven't had a bit of trouble with it until now. I replaced the transmission fluid about 10,000 miles ago.

Has anyone experience something like this before?

Thanks again!

 

[kitacamry]

This is my first post, so thanks in advance for everyone's patience and, hopefully, help!

My wife's 2004 V6 Camry is not happy. As you accelerate from a stop, the automatic transmission will go from first gear to second, and then sometimes just drop spontaneously into neutral. I replaced the transmission fluid about 10,000 miles ago.

Has anyone experience something like this before?

Thanks again!

:welcome:

I would 1st like to wish you good luck in getting this taken cared of .... it's dangerous.

I don't have any answers, but may I ask what type of AT fluid was used for the replacement?
If if wasn't synthetic, that might be a cheap 1st response, to replace it again with syn AT.
Castrol Import TransMax Multi-Vehicle: Specifically made for import vehicles it meets the JASO-1A requirements for Toyota Type T-IV is one such syn AT fluid, available at Walmart for $6/qt (quarts only, not the stuff in the gallon jug, as I myself have learned.)

...again, good luck.

 

[Pvt-Public]

quarts only, not the stuff in the gallon jug, as I myself have learned.

Why? Is the Castrol Import TransMax Multi-Vehicle in gallon containers different than the Castrol Import TransMax Multi-Vehicle in quart containers?

 

[leakyseals]

I replaced the transmission fluid about 10,000 miles ago.

Has anyone experience something like this before?

The 02+ transmissions as a whole are rock solid if maintained properly. My 02 gets nothing more than drain and fills every other year and its perfect at +300k.

Transmission Questions..

• You went 90k on the original fluid?
• When you say replaced the fluid, please provide detail. Did you do it, the dealer, jiffy lube, etc.
• Full replacement or partial?
• What fluid brand was used?
• Verify level is correct.
• When it slips is it warm or cold?

Yes the speed sensors can foul with brake dust, rust, wire gets cut, brakes may be shot, etc. That sensor is used by many systems and will trigger the lights you describe. Any wandering mechanic in his truck can fix that in your driveway. I have a guy in my area, call him up, he drives and repairs my car in the work parking lot. Cheap. You can find them just gotta look in classifieds, CL, friends, ask around..

 

[Pvt-Public]

Yes the speed sensors can foul with brake dust, rust, wire gets cut, brakes may be shot, etc. That sensor is used by many systems and will trigger the lights you describe.

I agree completely, but a $4000 est for rear wheel speed sensors, is a bit unrealistic. And the rear wheel speed sensors would not cause the speedo to go to 0 and the trans to neutral out. For this I would suspect the speed sensor on the trans, but still that estimate is still way out of line even if it included this sensor. If the trans fluid was replaced correctly with the correct fluid I would take it to an independent trans shop, not a chain store not the AAMCO, Cottman types.

 

[kitacamry]

why? Is the castrol import transmax multi-vehicle in gallon containers different than the castrol import transmax multi-vehicle in quart containers?

Yes! The gallons at Walmart have a DIFFERENT chemistry than the quarts...you have to read carefully to catch the difference.

 

[PhantomCamOp]

Wow, thanks for all the help! The people on this forum are WAY friendlier than some of the computer nerd chat rooms I frequent...

The dealership gracefully waived the diagnostic fee and provided the following error codes:
•P0500 - Vehicle Speed Sensor
•B1785 - Front Occupant Classification Sensor
•B1650 - Occupant Classification System Malfunction

The first one I understand relates to the speed sensors. The other two have to do with the passenger seat occupancy sensors, for the SRS. That was an unrelated problem we asked them to also check. When I got the car back this morning, it appears they have reset the SRS and it is working normally.

Back to the problem at hand, the instrument panel and transmission misbehavior.

Regarding the ATF change: I did the job myself using Valvoline MaxLife Full Synthetic ATF. I'm not a mechanic by trade, but I have rebuilt several VW engines and I always do my own oil changes. To my knowledge, the ATF had never been changed, so it was very dirty. But we've been driving the vehicle without any trouble for almost 10,000 miles since then. The dealership asked me all about the transmission and my ATF change, but ultimately they didn't indicate any problems.

I drove the car to an independent mechanic today. On the way, I tried to recreate the problem in some kind of consistent way, but it seems random. At times, the speedometer drops to zero, but the transmission operates normally. At other times, the transmission fails to shift into third, but stays engaged. Then again, sometimes it disengages to neutral on its own. Going downhill with the engine in low gear, the transmission always stayed in gear like it should. Likewise, it never dropped out of gear while climbing a hill. The problem seems to occur on level ground at light or moderate acceleration. I will also say that the transmission always behaved normally when the instrument panel was working properly. If the problem were the ATF, I'd expect it to happen often enough so that occasionally it would act up when the instrument panel was normal.

So it seems plausible to me that vehicle speed sensors might be malfunctioning (P0500), but none of the codes indicate any problem with the ABS, even though the dash warning illuminates. Additionally, the ABS has never activated spontaneously while driving. So I don't know why the dealership is recommending replacement of the ABS actuator other than possibly $$$.

Thanks for reading my long-winded post! These intermittent problems are always the most difficult to pin down! I really appreciate any thoughts or advice anyone can offer!

 

[PhantomCamOp]

Sorry, I failed to answer some of leakyseals' specific questions:

Transmission Questions..

• You went 90k on the original fluid? Yes, to my knowledge.
• When you say replaced the fluid, please provide detail. Did you do it, the dealer, jiffy lube, etc. I replaced it myself.
• Full replacement or partial? I drained the pan, but I didn't flush the TC.
• What fluid brand was used? Valvoline MaxLife Full Synthetic
• Verify level is correct. Sorry, I haven't check this recently!
• When it slips is it warm or cold? Only when its warm, as far as I can tell, but the instrument panel thing happens cold or hot.

 

[Pvt-Public]

OK that clears some thins up, in your original post you said rear wheel sensors. I would check the wiring to the vehicle speed sensor of the trans and probably just replace that sensor depending on cost myself. Make double sure the trans fluid is at the correct level. Remember the trans needs to be at full operating temp for accuracy. If that doesn't help next thing for me would be an independent trans specialist.

 

[Pvt-Public]

The gallons at Walmart have a DIFFERENT chemistry than the quarts

Good to know thanks. ALWAYS read the labels there just might be some important stuff there!!

 

[kitacamry]

Good to know thanks. ALWAYS read the labels there just might be some important stuff there!!

The gallon jug SAYS it's for Toyota, Nissan, Honda....but it's not what we're supposed to use...

 

[hardtopte72]

Yes! The gallons at Walmart have a DIFFERENT chemistry than the quarts...you have to read carefully to catch the difference.

You are confused.

Castrol Transmax Import Multi-Vehicle is the same in quarts or gallons.

Your issue that day was the you brought a Gallon of Castrol Transmax Dex/Merc. Which isn't compatible with Toyota T-IV (intended vehicle).

The only fluids that are different quart to gallon is the Valvoline Import Multi-Vehicle. In one gallons it's a newer thin viscosity WS compatible fluid. In the 1 quart it is the older thicker fluid.

 

[leakyseals]

The Maxlife partial (+-33%) should be fine. Keep doing that once a year and you should not have any problems. Your on the right track, try cleaning the sensor off and if that doesn't work get it replaced. You should be able to order the part, find somebody to swap it out cheap.

 

[kitacamry]

You are confused.

Castrol Transmax Import Multi-Vehicle is the same in quarts or gallons.

Your issue that day was the you brought a Gallon of Castrol Transmax Dex/Merc. Which isn't compatible with Toyota T-IV (intended vehicle).

The only fluids that are different quart to gallon is the Valvoline Import Multi-Vehicle. In one gallons it's a newer thin viscosity WS compatible fluid. In the 1 quart it is the older thicker fluid.

I can be easily confused...that is a given...

I know/understand THAT...but AT WALMART the gallons are DEX/MERC not the T-IV...which is what I meant by the warning...unless things have changed, Walmart doesn't stock T-IV in gallons....

 

[PhantomCamOp]

In your original post you said rear wheel sensors.

The service agent at the dealership led me to believe it was the rear wheel sensors. He even went into a bit of detail about how the sensors were integrated into the wheel hub and were a pain to replace. However, when I picked up the car and saw the diagnostic report, it definitely said P0500, which is the vehicle speed sensor code, unless someone here can tell me how the wheel sensors would also be implicated.

Am I right in presuming that the vehicle speed sensor is attached to the transmission? Is it easy to access? As soon as I post this response, I'll do a search and find out, I'm sure!

Thanks again everyone!

 

[hardtopte72]

I can be easily confused...that is a given...

I know/understand THAT...but AT WALMART the gallons are DEX/MERC not the T-IV...which is what I meant by the warning...unless things have changed, Walmart doesn't stock T-IV in gallons....

I think that is Walmart specific.

I just wanted to make sure our viewers didn't think the formulation between Castrol Transmax Import Multi-Vehicle is different between quarts and gallons.

Summary:

1. Castrol makes several Transmax brand transmission fluids.
2. Their Import Multi-Vehicle and Dex/Merc are not interchangeable on Toyota T-IV transmissions.
3. Import Multi-Vehicle may be sold as one gallon jugs depending in your location.
4. Dex/Merc is not compatible with a T-IV transmissions however both fluids will be fine in an older T-III/Dex III Toyota Transmission.

 

[mcgill_redmen]

Hello!
I see a lots of good review from walmart.com , amazon.com, clublexus & toyotanation mentioning Valvoline Maxlife dex/merc ATF as an substitute replacement for Toyota T-IV fluid. Any recommendations?

Here's the jug pic of the ATF fluid.

:thanks:

 

[doityourselfer1955]

Wow, thanks for all the help! The people on this forum are WAY friendlier than some of the computer nerd chat rooms I frequent...

The dealership gracefully waived the diagnostic fee and provided the following error codes:
•P0500 - Vehicle Speed Sensor
•B1785 - Front Occupant Classification Sensor
•B1650 - Occupant Classification System Malfunction

The first one I understand relates to the speed sensors. The other two have to do with the passenger seat occupancy sensors, for the SRS. That was an unrelated problem we asked them to also check. When I got the car back this morning, it appears they have reset the SRS and it is working normally.

Back to the problem at hand, the instrument panel and transmission misbehavior.

Regarding the ATF change: I did the job myself using Valvoline MaxLife Full Synthetic ATF. I'm not a mechanic by trade, but I have rebuilt several VW engines and I always do my own oil changes. To my knowledge, the ATF had never been changed, so it was very dirty. But we've been driving the vehicle without any trouble for almost 10,000 miles since then. The dealership asked me all about the transmission and my ATF change, but ultimately they didn't indicate any problems.

I drove the car to an independent mechanic today. On the way, I tried to recreate the problem in some kind of consistent way, but it seems random. At times, the speedometer drops to zero, but the transmission operates normally. At other times, the transmission fails to shift into third, but stays engaged. Then again, sometimes it disengages to neutral on its own. Going downhill with the engine in low gear, the transmission always stayed in gear like it should. Likewise, it never dropped out of gear while climbing a hill. The problem seems to occur on level ground at light or moderate acceleration. I will also say that the transmission always behaved normally when the instrument panel was working properly. If the problem were the ATF, I'd expect it to happen often enough so that occasionally it would act up when the instrument panel was normal.

So it seems plausible to me that vehicle speed sensors might be malfunctioning (P0500), but none of the codes indicate any problem with the ABS, even though the dash warning illuminates. Additionally, the ABS has never activated spontaneously while driving. So I don't know why the dealership is recommending replacement of the ABS actuator other than possibly $$$.

Thanks for reading my long-winded post! These intermittent problems are always the most difficult to pin down! I really appreciate any thoughts or advice anyone can offer!

I can't give any advice on those codes. But when I called a trans guy that I trust to do a trans fluid change, he told me to just drain the pan and refill with the original Toyota Type IV from the dealership. He only uses synthetics on rebuilds. And the fluid from the dealership was no more expensive than brands from the store, so why take a chance with a substitute? Also, if you compare different brands, one may say that it is good for manufacturers A, B, C, and D; another will say it's good for B, C, and D, but not A...My question is, how is that possible? That seems like a good way to put gremlins in your transmission...stick with the original.

 

[leakyseals]

Hello!
I see a lots of good review from walmart.com , amazon.com, clublexus & toyotanation mentioning Valvoline Maxlife dex/merc ATF as an substitute replacement for Toyota T-IV fluid. Any recommendations?

Yes Maxlife dex/merc ATF is compatible with T-IV. No complaints reported after use. Works good as PS fluid also.

 

[PhantomCamOp]

I appreciate everyone's advice about ATF. I just don't think that is the issue here.

The independent mechanic has confirmed what the dealership found; a faulty ABS actuator. He says his tests indicate that it isn't communicating with the ECM. Its a very expensive part, and apparently not a very common unit to fail. But THIS THREAD establishes precedent for my exact problem being related to the ABS actuator.

Has anyone attempted to replace one of these themselves? It looks easy enough to access--just six brake lines, one cable connector, and three bolts.