[Erkme73]

So my 2011 Sequoia is right at 180k miles. I purchased it about 1.5 years and it's been problem free. About 6 months ago I noticed that when chugging up a hill at slower speeds (maybe 30 mph) at a constant RPM, it felt like the engine would rev up slightly (maybe 100-200 rpm) and the pull felt a little less. I wasn't sure it wasn't a misfire, but no DTC were thrown. It was intermittent and infrequent enough that I'd forget about it before getting home. On one of the earlier service calls at the dealer, I asked them to check the transmission - which they reported as "everything checks out". I don't know what that means, and the dealer's technical prowess is sub-par (and that's being nice)

Over the last few weeks it has gotten noticeably worse. Now on climbs I can feel the pulling power drop by about 50% for about 3-4 seconds, then a thump as the full power reengages. RPM is staying relatively constant, so I'm certain it is the transmission. Some times, when it's cold, and I put it into drive initially, I press the accelerator, and it barely moves forward - almost as though I put in into neutral instead. After letting RPM back down and waiting a second, all goes back to normal.

Further complicating diagnostics is that most of the roads I travel are hilly and gravel - something that helps obscure the slipping.

There are no visible leaks (though I do park in gravel, so I may not have noticed any), no burning smells, nothing out of the ordinary.

I'd be happy to check (and maybe even change) the transmission fluid, but I was under the impression these were "sealed for life" devices - at least that's what the dealer has told me.

 

[twoheeldrive]

If you are very lucky, it could be that the transmission fluid is just low and needs to be filled up. The procedure to check and add is fairly complicated; about as difficult as changing the fluid, so if it was my vehicle, I would have the fluid changed and hope that takes care of it. Not so lucky... time for a replacement transmission.

You really should have been changing the fluid at 60,000 mile intervals. It's in the warranty and maintenance guide under "special operating conditions".

"Lifetime" fill is a marketing gimmick.

I hope a fluid change does the trick for you.

 

[Erkme73]

Well, I dropped her off at the dealer today. The service adviser wanted me to drive with the tech to make sure it was really the transmission causing the symptoms. So, I took him for a 10 minute drive. It behaved perfectly until we got to our first steep hill. While it didn't slip, it did thump a couple of times - like it does after a cycle of slipping. Tech felt it, and was sure it was the tranny, so back to the dealer we went.

I've left it with them to do more diagnostics. Tech had "heard" that flushing an a tranny with >100k miles, that had never been flushed before was a detrimental thing - but he didn't believe it to be the case. So they will perform a tranny flush - though he said he didn't think that this would do much for the symptoms since "by the time it starts slipping, the damage may already be done". Not too comforting, but I don't really have many other options.

They said IF the tranny has to be replaced, I should budget between 4-5K for a new one, or 3-4k for a used one (this includes 10 hours of labor @ $125/hr).

As for the vehicle history - I've only owned it since about 170k miles - and the detailed history stopped around 150k from previous owners. The girl at the service counter checked the history and said there was no record of Toyota ever having performed a tranny flush.

I have real reservations about this dealership's technical abilities - never mind any trust issues. If the verdict comes back requiring a new tranny, I will take it to the dealers in Knoxville or Chattanooga - both have much larger (and probably more capable) dealers - for a second opinion.

Interestingly enough, I have found a "used" transmission on Amazon of all places, for right at $1k.

 

[jgrauman]

My buddies 10 did the same thing. Tranny flush did the trick for him. Fluids break down. Dealership charged $200 for the flush with 14 qts

 

[Erkme73]

That sounds encouraging @jgrauman. I received a call from the service adviser today. She said the tech drove the Sequoia again today. He drove it up a hill and felt the 'thump' but not the slipping. He then drove a 2015 that he had on the lot for comparison and said it felt the same way. Thus, said the service adviser, "He thinks this is just the way these drive." See, told ya this is the most incompetent dealership...

I told her that if he didn't experience the slipping, then it wasn't doing it for him. I also explained that I have a 2007 5.7L Tundra and have a pretty good feel for how the tranny is supposed to feel. She relayed that back to him and he said he'd drive it home tonight to give it another test.

She asked if I still wanted to do the flush. I asked her if it involves removing the pan and replacing the screen/filter. She said no, it was only using a machine to do it. I'd love to know other's opinions on whether that is adequate. After watching a few YT videos on how to replace the fluid/filter, including how to mechanically bypass the cooler thermostat, it looks simple enough to DIY. I would think dropping the pan and getting everything spotless (including examining the magnets) would be far more revealing and complete than just hooking up a machine. But maybe I'm looking at it the wrong way.

FWIW, the machine flush is $225. I think I can get filter, gasket, and ATF for less than that.

I will know more tomorrow and will post it here.

 

[sdunlimited]

I'd be curious to hear how it goes for you if you do decide to pull the trigger on performing this service yourself. I plan to do the same on a 5.7L Tundra with ~245k on the clock in the near future. No slipping or clunking here but an occasional rough shift.

 

[johnsonman]

[/QUOTE].
I'd love to know other's opinions on whether that is adequate.
[/QUOTE]

I've had more than one vehicle flushed, transmissions and power steering units. The machine is connected to via hoses in/out of the transmission, usually where it connects to the radiator or external cooler.

It pumps a cleansing agent thru the entire system thru the normal route until it runs clear and clean, then they change over to your new fluid and pump it thru until all the cleaner is out.

It has issues with a transmission not wanting to shift when weather was cold and steering units that squeeled when cold.

It is superior to drain/fills or 'home flushes' because of the use of a cleanser.

Don't worry about the pan, magnets or filter for now, this will clean the system out. Luck.

 

[pihoqahiak]

Don't bother with only a transmission fluid flush. Odds are they will just put in an equivalent of fluid that they take out and not actually check the fluid level afterwards. Have them drop the pan and check for metal debris. Then make sure they actually check to confirm the fluid level is correct after the flush is completed. I'd ask them to take a picture of the inside of the pan once it is dropped. Seeing what is or is not in the pan is probably the most important next step for you (assuming the level is correct).

If you're going to change the fluid it definitely makes sense to pay the extra and have the pan dropped at the same time...unless you want to gamble that a fluid change will fix it and understand that if it doesn't, you'll end up needing to pay to drop the pan later +/- test the solenoids. This is coming from someone with a 1st gen that just had a planetary gear failure. A transmission is not something you want to just try things with. Personally, I think you have two choices 1) have them check the fluid level (if not done already) 2) drop the pan and decide where to go from there.

 

[Erkme73]

Ok, thanks for comments/opinions. Dealer called and said the trip home with the Sequoia did not reveal any slipping. However, tech said the rear diff is louder than it should be and I was quoted $2100 for used or 3200 for new. Now, I KNOW it is slipping on steep hills. And I know the rear diff won't slip (I think), so it seems they're ignoring (unable to find) the tranny problem, and instead focusing on a secondary issue.

The said the cost to drop the pan, change the filter, and do the change without the flush machine is $550. For that price I'm willing to do the DIY route... As for the rear diff, they sent me a video (I think they used a potato to film it) and you can hear a whine. Now I'm wondering if there isn't anything DIY that I can do to extend the life of what sounds like a bearing issue in the diff.

I'm going to pick it up tomorrow and will order the fluid, filter and gasket kit to do the pan sometime this week.

I've also reached out to a trusted transmission company out of Lutz, FL about having them inspect/repair/rebuild the tranny. The owner will be calling me in the AM to discuss options. I'll post follow up as available.

 

[Erkme73]

Just a quick update while I wait for all the fluid and parts to arrive... I spoke with the transmission guy who comes with great references. He's in FL, I'm in TN - but getting the vehicle to him would not be an issue so I have that as an option.

He was quite helpful in explaining what to do and what to check. He seems to think it is low on fluid, but told me to take pictures and send them to him so he could review and offer comments and suggestions. Heck of a deal.

My primary reason for contacting him was to get the opinion from someone who does this for a living on whether it is counterproductive to change the oil on a >100k mile tranny that has never been serviced. He said that it should do no harm. Pressure flushing, on the other hand, may. He said most anecdotal reports of failure after fluid change come from people who already have symptoms on a tranny that is on borrowed time. They have the flush performed, and then the tranny fails anyway - and they then blame it on the flush. Sounds good to me, and gave me the confidence to DIY...

I hope to get it up on stands over the weekend to do more diagnostics and check the fluid level (ATF won't get here until Monday). I'll also change out the rear diff fluid to see.

 

[5point9limited]

Following. Please keep us posted. This is the first transmission problem I've heard of on a Sequoia/Tundra. Best of luck.

 

[Erkme73]

Thanks for the well wishes. After discussing my problem with another Tundra owner, he had an interesting story to tell about his 2003 Tundra with 245k miles. He said when he first bought it (with those high miles) it would have similar slipping and clunking. He changed the rear diff fluid and the problems resolved. That got me thinking about my rear diff. Dealer said it the sound was abnormal. Their first recommendation was to replace it - no fixing, no servicing.

I'm still waiting for my WS ATF fluid to get here (tomorrow), but the 75w90 diff fluid and crush gaskets arrived on Friday. So, this weekend, I got the Sequoia up on 4 jack stands and managed to drain the rear diff. Fluid was dark, and the magnet was completely covered with filings - though they were all very fine silt - no chunks or pieces I could actually feel. There was no fluid coming out of the fill port when I opened it. I refilled it with just shy of 4 pints (as per manual) and it just starting dripping from the fill port.
Unfortunately, I didn't test for sounds BEFORE servicing. DOHHH... But, after the change, I did run it up to about 70 MPH while on the stands and heard no whining/whirring sounds... I wasn't directly under the vehicle (I had no one I trusted with my life available to operate the accelerator). I have also not had a chance to test drive it up the local steep hill that always gives me problem. Though, I may do that tonight just so I can post an update here.

Anyway, if it turns out the thumping and slipping are gone, I still plan on doing the pan-drop and fluid change on the tranny. Likewise, after reading 3.8 QUARTS instead of PINTS, I bought way too much 75w90, so I'll change out the front and transfer case as well. FWIW, the fluid is designed for limited slip.

 

[Erkme73]

Alright, after some test driving, the problem is still there. And, after trying a few different scenarios, I know the following:

1. In manual (S) mode, leaving it in first gear completely eliminates the symptoms - regardless of 2/4h/4l mode.
2. In automatic (D) mode, the slipping/thumping occurs at a speed where the transmission would normally attempt to switch into the next gear - though it doesn't actually shift.
3. In manual (S) mode, leaving it in second gear still produces the symptoms at about 1200RPM/10MPH. Presumably even when selecting 2nd gear, it still starts in 1st?

So, I think this fairly conclusively eliminates all points between the transmission output and the wheels - i.e. diffs, transfer case, etc.

If I had to guess, I'd say there is some kind of hesitation or failure to commit to switch to the next gear. It's like it thinks, "Ok, start the shifting sequence... ah, never mind". On anything other than moderate/steep hills this doesn't happen (or it isn't noticeable), so the hesitation appears to be load-based.

I know absolutely nothing about transmissions, but in the many YT videos I've watched, I see lots of comments about the three different solenoids - which are visible with the pan removed. One locks, one shifts, and I forget what the third one does. Anyone know if this is something I can verify/clean/replace? It really does seem like more of a sensor/control issue than a truly mechanical (i.e broken/stripped gears) problem.

 

[Erkme73]

Today was the day... I did all the steps needed to check transmission fluid level (locked the thermostat valve with a drill bit, jumpered OBDI pins to show when temp was ideal) and found just a tiny drop or two coming out of the check port. It wasn't a trickle, so I was hopeful it was low.

I drained all the fluid from the pan, dropped the pan, replaced the filter, reinstalled the pan (with new gasket) and filled it with 5 quarts. I then disconnected the return line from the cooler (at the tranny) and ran the engine until the output was cherry red and started to gurgle. I then filled in another 4 quarts and ran the temp back up to ideal values. Opened the check port, and drained until there was just a slow trickle. Removed the drill bit from the thermostat, and got her off the jack stands. My barn looks like I killed someone with ATF. I am one messy worker.

I promptly took her to the hill that has always caused symptoms. And... drum roll... symptoms are still there. However, they are not as pronounced. It still feels like it's slipping as it gets to a gear change, but the thump that was present before is much more subtle now.

I found no debris in the pan or magnets - just some very fine powder/silt one would expect. The oil was dark, but still translucent. Compared to the clear red new fluid it was definitely darker/browner, but no bad smells or signs that it was anything other than well used.

I had considered removing some of the solenoids on the valve body, but after seeing how many there were, and having no clue which of them would even be involved in the symptoms I was experiencing, I opted to just leave them alone. Everything on the valve body look clean and in place. No debris or other signs of damage.

That said, I think I'm just going to "live with it" for now. Unless the symptoms get worse, or new ones show up, I'll try to ignore it. If it starts to happen on flat roads and is easily reproduceable, I will take it to the trusted transmission shop in FL. The owner there said I should not expect much of him if he cannot reproduce/experience the problems himself.

So for now, this should be the end of this thread for me...

 

[sdunlimited]

Thanks for the details. Sorry to hear that it didn’t 100% fix your issue.
How would you rate the difficulty of doing this?
Was any part more difficult than others?
The process seems mildly daunting/tedious compared to a “normal” transmission with a dipstick.
Have you considered trying anything like Lucas Transmission Fix? There are some decent reviews online and on YouTube claiming that it does help with situations like yours.
I’ll be going this route in a few months once the weather warms up and allows for it. I’m garage-less in the northeast. This project can wait

 

[Erkme73]

I think anyone able to follow directions and YT videos ought to be able to do do this. It's not difficult. My problem was that I kept knocking stuff over. For example, I was using a small bottle pump to push the new ATF into the tranny via a 6' 1/2 ID hose. The pump was made for bottles with a smaller throat - so it just laid on top of the gallon-sized ATF container. IT worked, but it was messy. And because of how clumsy I am, I of course had to knock over the gallon jug with my foot as I was under the vehicle with my creeper. It didn't just spill. It effing sloshed... everywhere... on my pants, shirt, creeper, and the floor.

Self-inflicted problems. But if you are not as inept with physics as I am, it should be a breeze. I think if I ever have to do it again, I'll be able to do it twice as fast, and hopefully not quite as messy.

Really the tricky part was with the oil cooler. Finding the correct hose and location to deteatch and tie in another section of hosing so that the old fluid can be pumped out wasn't as easy as shown in the YT videos. They were too zoomed in to see exactly where to (dis)connect. It turns out, there is a much simpler location right at the tranny - just above the cross member that goes under the tranny. It's at the heater/thermostat - there are four hoses. Two are heated coolant. The other two are supply/return to/from the tranny cooler. The lower of those two (the bottom of all four) is the one that gets separated. The metal tubing coming from the cooler shoots into the collection pan and when it goes from dark brown to cherry red, your reassemble, add another 4 quarts, and proceed with the level check. Easy (messy) peasy.

 

[twoheeldrive]

I think anyone able to follow directions and YT videos ought to be able to do do this. It's not difficult. My problem was that I kept knocking stuff over. For example, I was using a small bottle pump to push the new ATF into the tranny via a 6' 1/2 ID hose. The pump was made for bottles with a smaller throat - so it just laid on top of the gallon-sized ATF container. IT worked, but it was messy. And because of how clumsy I am, I of course had to knock over the gallon jug with my foot as I was under the vehicle with my creeper. It didn't just spill. It effing sloshed... everywhere... on my pants, shirt, creeper, and the floor.

Self-inflicted problems. But if you are not as inept with physics as I am, it should be a breeze. I think if I ever have to do it again, I'll be able to do it twice as fast, and hopefully not quite as messy.

Really the tricky part was with the oil cooler. Finding the correct hose and location to deteatch and tie in another section of hosing so that the old fluid can be pumped out wasn't as easy as shown in the YT videos. They were too zoomed in to see exactly where to (dis)connect. It turns out, there is a much simpler location right at the tranny - just above the cross member that goes under the tranny. It's at the heater/thermostat - there are four hoses. Two are heated coolant. The other two are supply/return to/from the tranny cooler. The lower of those two (the bottom of all four) is the one that gets separated. The metal tubing coming from the cooler shoots into the collection pan and when it goes from dark brown to cherry red, your reassemble, add another 4 quarts, and proceed with the level check. Easy (messy) peasy.

Glad you got it done... too bad it didn't help much, but at least you are still on the road. Where did you find Toyota WS fluid in a gallon jug? I've only seen the quart bottles.

 

[Erkme73]

Glad you got it done... too bad it didn't help much, but at least you are still on the road. Where did you find Toyota WS fluid in a gallon jug? I've only seen the quart bottles.

Very perceptive... Yes, it wasn't true Toyota-branded WS. But after being quoted $10 a quart by the local dealer, I did a bit of research and came up with this: https://www.amazon.com/gp/product/B07M94B6V6/

I know there is probably debate as to whether it is identical to WS, but seeing the glowing reviews and high rating, I lost no sleep over using Idemitsu. It's actually 5 quarts, not a gallon... Thus, bigger mess when you spill it!

 

[sdunlimited]

I definitely understand what you're saying about the self inflicted problems. Sometimes the easiest jobs can get away from you. I was doing a thermostat years ago on a 4.7L 8cyl Jeep motor which is ridiculously easy. Two broken bolts stuck in the block, a $300 tow bill and $200 mechanics bill later I had the some costly tuition to forever seer into my brain the difference between foot pounds and inch pounds...

BTW, were you on ramps, jacked up, leveled in the air or flat on the ground when you were checking the fluid level in the transmission?

 

[MtnClimber]

I drained all the fluid from the pan, dropped the pan, replaced the filter, reinstalled the pan (with new gasket) and filled it with 5 quarts. I then disconnected the return line from the cooler (at the tranny) and ran the engine until the output was cherry red and started to gurgle. I then filled in another 4 quarts and ran the temp back up to ideal values. Opened the check port, and drained until there was just a slow trickle. Removed the drill bit from the thermostat, and got her off the jack stands. My barn looks like I killed someone with ATF. I am one messy worker.

Not trying to be critical, but for the sake of others reading this, something doesn't add up. The system capacity is about 12 qts and you said you put 9 qts back in. Did you measure how much was drained out? In my experience, the output doesn't run cherry red until about 12 qts of old fluid comes out. Maybe you meant to say you filled with 4 qts twice (5+4+4 = 13?).

Also, not sure what videos are out there, but from what I have read its not advisable to suck air into the system. So when I did this I pumped out no more than 3 qts at a time just to be safe.