[mainsoda]

2008 FJ Cruiser 200K miles automatic transmission.

I have a shudder and it's drivetrain. All week I have started to notice a faint but growing growl. Then yesterday the shuttering started to become unmistakable shake when accelerating and decelerating. As I coast to a stop I can click my automatic transmission over to neutral and shuttering stops completely. Staying at a steady speed is just as smooth as can be.

I was hoping it was a differential issue so I changed the fluid tonight and it was old and stinky, but no metal flakes at all.

So here I am and I think I'm looking at a transmission or a transmission part. It almost acts like a clutch, but they don't have such a thing on an automatic transmission, do they? Torque converter?

What do you guys think?

 

[FJtest]

At exactly what speeds (or speed ranges) does the shuddering occur?

Does it occur if you leave the transmission in 4th gear?

 

[norm356]

Also, have you ever serviced the AT fluid?

 

[mainsoda]

At exactly what speeds (or speed ranges) does the shuddering occur?

Does it occur if you leave the transmission in 4th gear?

It doesn't occur at any particular speed. I can feel the vibration when the engine has stress on it. Under acceleration or engine braking. I have an ultra gauge too and the transmission is running at normal temperatures.

 

[mainsoda]

Also, have you ever serviced the AT fluid?

I have not, I should do that next I think.

 

[Iconic_]

Sounds like the transmission shudder. Change the fluid.

 

[FJtest]

Again, does this "shuddering" completely disappear if you drive in 4th gear rather than D (5th gear)?

Gotta make sure what you are experiencing is a true driveline "shudder" originating in the transmission or torque converter clutches vs a 'rattle' from something as simple as the exhaust crossover pipe contacting the frame.

The clearance between the crossover and the frame is small, and any 'sag' in the engine or transmission mounts can allow the engine to move enough (under acceleration OR deceleration) to permit the exhaust piping to contact the frame.

Also, it doesn't take much of a hit on the crossover pipe against a rock or ice to distort the pipe and reduce clearance even further.

Have someone get in the driver's seat, set the parking brake, start the engine, raise RPM to ~850, and shift between D and R while you are on the ground next to the vehicle watching how much the engine, transmission and exhaust system moves while shifting between D and R, and listening for any metal-to-metal contact.

Also check for cracking around the edges of the engine mount plates where they are welded to the frame rails - this can allow additional engine movement that results in rattling noise.

 

[mainsoda]

I have updates:

Decided to do the partial transmission fluid change. I took out the old stuff which was thin and orange colored. I measured the amount very precisely and put the exact same amount back in. I warmed the transmission to 120 degrees and went to do my overflow drain and nothing. I tried adding a little more and still nothing. So I added a whole extra quart and now I got about 2/3rds of a quart to drain out.

Which says to me that my transmission was about 1/3rd of a quart low. Not bad for 200,000 miles.

I took it for a test drive and found it seemed to have the same shudder at all speeds when accelerating and decelerating. But as I drove the shuddering seemed to begin to improve. Then after about 30 minutes it was mostly gone. It always seemed intermittent and now even more so. I guess I have to drive it more to be sure.

Does this sound like anything you guys have seen before? Is it possible that this is getting better and that it may eventually go away? Or is this just a placebo effect because I want it to go away?

Thanks for all the help so far.

 

[Sanderhawk]

Of all the threads I`ve read on this the fluid change is not instant but gets better as you drive it. So I guess you`ll find out soon. I change my fluid once a year so I never have had the shudder.

 

[FJtest]

The WS is low viscosity, and the usual reddish color when new, but quickly darkens even with 'normal' use.

You're saying the fluid you drained out was distinctly "orange"?

That's bizarre, and certainly not the original factory-fill WS with 200K miles on it.

Given that you've only partially diluted the entire volume of fluid that's circulating in the transmission, torque converter and cooler, I'd repeat the pan-dump-and-fill cycle at least 4 more times to get the majority of whatever was in there, out.

Just out of curiosity, what color is your engine coolant? Toyota red or pink, or something else?

 

[mainsoda]

Of all the threads I`ve read on this the fluid change is not instant but gets better as you drive it. So I guess you`ll find out soon. I change my fluid once a year so I never have had the shudder.

This is good to hear.

 

[mainsoda]

The WS is low viscosity, and the usual reddish color when new, but quickly darkens even with 'normal' use.

You're saying the fluid you drained out was distinctly "orange"?

That's bizarre, and certainly not the original factory-fill WS with 200K miles on it.

Given that you've only partially diluted the entire volume of fluid that's circulating in the transmission, torque converter and cooler, I'd repeat the pan-dump-and-fill cycle at least 4 more times to get the majority of whatever was in there, out.

Just out of curiosity, what color is your engine coolant? Toyota red or pink, or something else?

I was going to drive some more and see what results I get especially with the fluid being down 1/3rd of a quart.
But if it is not cured of the vibration I have more swaps for future mainsoda.
I've changed my radiator a few years ago and it was pink and I replaced it with more pink.

 

[FJ-6MT]

I have a shudder and it's drivetrain. All week I have started to notice a faint but growing growl. Then yesterday the shuttering started to become unmistakable shake when accelerating and decelerating. As I coast to a stop I can click my automatic transmission over to neutral and shuttering stops completely. Staying at a steady speed is just as smooth as can be.

Servicing the transmission fluid is always a good idea and apparently needed doing anyway, but what you describe doesn't sound the the typical AT shudder that people with 5AT FJs usually have. Did you check the drive shaft universal joints for play? Even a tiny bit can make a lot of noise and vibration sometimes.

 

[mainsoda]

Servicing the transmission fluid is always a good idea and apparently needed doing anyway, but what you describe doesn't sound the the typical AT shudder that people with 5AT FJs usually have. Did you check the drive shaft universal joints for play? Even a tiny bit can make a lot of noise and vibration sometimes.

I checked the drive shaft itself and it didn't seem to have any play in it. The issue seems very inconsistent and erratic so you make a good point. I'll have to take a closer look at those U joints and maybe change them just for the hell of it.

 

[Kaiju]

Perform a couple more fluid changes with some driving in bewteen to get more of the old stuff diluted. Make sure the transmission is between 115 and 130 F measured at the pan, infrared thermometer if you don't have a way to read the OBD II trans temp output, and you're on level ground when you check the final fluid level.

 

[jshea132]

IF it is the dreaded AT shudder the fix is to put two 2oz packets of Dr. Tranny into it. This occurs when accelerating lightly on fairly flat road, and the tranny gets to fifth gear at about 40 mph. Shifting back to 4th gear usually will stop this. Its on Amazon.
Lubegard 19610 Dr. Tranny Instant Shudder Fixx 2 Ounce 2 Pack
4.54.5 out of 5 stars (1,842)
$18.99$18.99
I put it in my 2007 more than a year ago and it has not done it since. this was after a very expensive full flush and refill which was no help at all. Good luck!

 

[mainsoda]

UPDATE: I'VE FIXED IT COMPLETELY!!!!

Huge appreciation to FJ-6MT who suggested I take a closer look at the U Joints.

With the drive shaft on I couldn't tell anything was wrong, so I rolled up my sleeves, cracked out the torch and got to removing my Wisconsin winters drive shaft. Once I got the bugger off I found this.

My front universal joint

After taking it all apart I found no needle bearings in two sections of the U joint. Where did they go? Were they reduced to powder after 200,000 miles?

It's midnight and my garage is trashed. I'm way to tired to clean it up, but I am so happy to have found the problem and fixed it with 2 U joints. Life is good and thanks everyone for the help, especially FJ-6MT, you are a genius man!