Torque Converter Shudder Upon Disengagement

Hi All!

Would like to get the group's opinion on a possible issue I've noticed in the first 6 months owning the Tundra. First of all, it's an amazing truck in every way and I've really enjoyed it so far!

Truck: 2016 - SR5 - 4WD - 5.7 - 55,000 miles

Issue: When gradually coming down from 50 mph, in 6th gear, with the torque converter still locked up, still lightly on the throttle, I sometimes experience a pretty harsh bang and shudder when the torque converter disengages around 38 mph. It varies in severity, but at times can be a little concerning.

Question: Any thoughts on what might be causing this? Does anyone else experience this? Am I being too sensitive to the mechanical workings of the truck? Can this be dismissed as just "driving like a truck"?

Many thanks in advance for any feedback the group can offer.

 

That's not normal.

If you don't know the history of the truck, I would also check or change the trans fluid.

You should still be under warranty! Isn't it 5yrs/60K?

 

change transmission fluid and have it checked for coolant contamination. (dealer should have to tool because of the camry coolant contamination issue). if coolants in the fluid, replace the transmission cooler puck thing... thats typically what causes shudders.. but they usually will shudder under light throttle right before the shift around 30-40 mph

 

I have the same truck with 83k. Occasionally mine does some funky stuff when slowing down. Harsh shifting, jerkyness, etc.

I've had my transmission fluid changed at 50k and keep up with all the maintenance. I don't know what causes it and it's not consistent. I just roll with it.

I also get some driveline vibration between 37-42mph. If I stay in that range it does it the whole time you're driving at those speeds. I've never had it checked and it goes away at all other speeds. Been doing that for as long as I can remember.

 

2017 Limited 4X2 here...

I have experienced similar "shudder". Usually in the 30-40 mph range and ONLY on deceleration. It doesn't happen all the time but seems to show up when I am trying to decal then have to speed up again. Seems like it is the 5th to 4th gear change.

My trans fluid was changed by dealer about 15K ago. Trans shifts smooth as butter otherwise. I have read other posts that people complain about the "clunkyness" of these transmissions. I guess that is what we are seeing.

 

38 mph or so is when the truck will force a downshift from 6th to 5th. It could be old transmission fluid with its friction modifiers used up. I ran into that with towing a few years back. The first sign of the fluid needing changing was the truck shifting much more harshly. That was more apparent in the 1-2 and 2-3 upshifts though.

That said, mine has never been particularly smooth on that downshift even when new. The transmission is forced to accelerate the engine up from 1000 rpm and doesn't seem to get dampened too well when spinning that slow.

 

Update: I had the fluid drained and refilled at the Toyota dealer. The problem I was experiencing above has diminished a great deal... good enough to live with. Issue resolved.

While the truck was in, I also had the parking brake adjusted so it would hold a little bit better than it was. So the complete service consisted of the fluid service and brake service.

Now I have another issue. When i picked the truck up all was fine until I got on the highway. At about 60 mph, the truck began to shake like it had severely out-of-balance tires. As i let off the gas, it seemed like it actually got slightly worse. I pulled off the highway to head back to the Toyota dealership. Before I got back on the highway, I inspected all wheels and tires for any oddities, smelled for burning brakes etc... all checked out fine. Returning to the highway, the shake was gone. I took the truck up to about 75, no more shake. I guessed that it had something to do with fluid change... maybe refilling the torque convertor or something beyond my ability to understand, so I turned back around and headed home.

Fast forward 3 weeks after driving around town and on the highway with no issues... I again experienced the same thing today, albeit at a little faster of a speed, at about 80mph on the interstate. Like before, the truck was shaking, steering wheel and all, like it had 4 severely out-of-balance tires. However, after I came down from speed and then returned back to highway speeds, the shake was gone.

To present this issue a little more clearly, the truck never had an issue like this until I had the trans fluid changed and parking brake serviced, so I can't help but to think it's related to the service. Does anyone have any idea what's going on? Does it sound like it's low on fluid? Maybe too much fluid? Maybe the torque converter is yet to reach full fluid capacity? Could the parking brake be slightly sticking? Does increased speed and centrifugal force play into the fluid or brakes "settling in". With the exception of the 2 shaking episodes mentioned above, the truck drives and shifts smoothly in the city, and on the highway.

Many thanks in advanced for any thoughts from the community on this matter.

 

How long do you warm up and/or slow(er) driving before going 80mph?
Is the engine/trans fluid warmed up before hwy speeds?

Just in case, check the lug nuts and drive shaft lube, rear diff fluid, etc.

Still under warranty though!

 

Definitely check those lug nuts. Always check within 50 miles of driving after a tire has been removed/installed, and again 50 after that, and again no more than 500 after. Heck I check them immediately after I get the truck after a near incident a few years back when I just got new tires. Felt a vibration about 20 miles down the road followed shortly afterwards by brakes making a strange sound. I stopped immediately to check. Front left rim had never been torqued and the lug nuts were at least two full turns out.

edit: for funsies I looked in the manual. 154 lb-ft for steelies (spherical seat nuts), 97 lb-ft for alloy rims (shank nuts w/ washer).

As for the torque converter, that's engine rpm, not driveshaft/wheel rpm, and would be felt more in low gear + high acceleration if there was a balance problem.

Were the tires cold? Both my Tundra and Tacoma would have a similar issue where cold tires would keep a flat spot for a few miles in the winter. Then if I went fast enough it was as if it would cause a sympathetic vibration in the driveline until I slowed it way down. The two piece driveshafts have that midship support bearing mounted in a very soft cushion and I think if a strong enough vibe starts it can't dampen it until its revs come down. It's also possible it may be caused by cold grease in the u-joints. Either way I think the Tundra is worse on this one.

Or it could be a bad tire. Once drove a Bridgestone car tire that would randomly go way out of balance after a few hundred miles. Turned out the steel belts were shifting inside the rubber. Somehow it never delaminated when going down the road. That one was a bit scary to find out

 

@TTund16: I takes 15 minutes to make it out to the highway, so yes, the engine and drivetrain had ample time to reach operating temperature. Will check the lugs per your recco. If that doesn't help, I'll check the driveshaft lube (zerks I'm guessing?) and rear diff fluid, which is my next item to be changed before 60K.

@endagon: Thanks for the informative feedback. I will def check the lugs per your recco. And yes, I'd guess the tires were on the cold side... so maybe that plays into this issue. And the tires would have been on the cold side the first time this happened as well.

I feel a little better now... I have a tendency to obsess on worst-cast scenarios first, which I wish I wouldn't do... and trust the fact that I bought a Toyota for reason and trust their amazing reputation for quality and reliability.

 

@55K now, I would go and document all these with the dealer before the 60K warranty is over ... just in case!

 

I have a '15 SR5 4x4 5.7L and your initial tranny shudder sounds exactly like what I get occasionally. When I am coasting to a stop, right around 60km/h (~40mph) I sometimes get a bit of a jolt, like I hit an expansion joint in the road or something. Ive assumed its the torque converter and ignored it. I'll check my tranny fluid and see what it looks like. Maybe I'll have it changed at the dealer and see if it helps me out as well.

 

Hey guys I have a 2018 tundra 6 k miles on it. I have a 2-1 level kit on it. Still drives like factory. Only thing I’ve noticed is a slights vibration accelerating from zero to about 20 mph . Thought it was the drive shaft so installed a 5/8 cab drop got a little better but noticed the vibration is also there on park and neutral.. right between 1,500 rpms and 1,700 rpms and then goes away. Any ideas on what it can be? I means it’s practically brand new. Is that just how the engine works.

 

If you go back to the dealer I gotta know....

 

I have also experienced this torque converter shudder when driving my 2007.

My questions:

How concerned should I be?
Will this problem get worse? (the truck has almost 300,000 miles).
Will the TC fail, or will it just keep trucking with the occasional shudder?

I can purchase a new OEM TC for under $800.00


TSB: TC018-07 Revised