I'm not seeing a TON of info on the shudder problems. But there was a few ... random threads on it that didn't provide a ton of info.

From what I've read elsewhere, the trans shudder issue sounds more like a TQ issue not a trans issue. Can anyone confirm that?

I know GM sent out a bulletin having dealers/repair shops use a different style mobile 1 oil on their transmissions vs their own products.
I've not seen/read any of the ford bulletins on this. But the reading basically looked like TQ shudder due to poor friction in the ATF. Which explains why a lot of people are seeing good results from a flush/filll.

Now, I'm sitting with a truck I don't know much about because I got in the way you don't want to get a new vehicle, Dad passed away, and I'm slowly fixing the random stuff on it chasing vibrations.
So, new front wheel bearings (4wd) and a tie rod end with an alignment. Vibration was still there.
Feels like a drive shaft vibration, but couldn't find a bad u-joint.

The part that is trippy about all this shudder stuff is that you can feel it in the steering wheel.
I don't really know how to detect if anything is bad. And I need to hollar at the dealership to see if the trans was ever replaced on this.
The folks that I talked to seemed to not know about any issues with this 6 speed transmission. However, it seems that if not regularly serviced, based on the few posts ive seen in here, it can have some fun issues.
A few family members said something about it having trans problems and it getting fixed at the dealer.
And I also saw a deal with there being an investigation on these 6 speed auto's as well right now with some weird issues. The random downshifting issue, in other transmissions at least, is usually a worn internal clutch issue. Or some weird valve body issues.

Anyways.

I threw in some of the trans slip friction modifier in there to see if it goes away or not.
At least it will stop for a minute while I get more things under control with the other parts that come with these situations.
And then I'll do a flush on it and put that better trans fluid in that's fixing the GM issues.

It's fascinating how we put oil in to make things not damage themselves, but at the same time put things in that need to grip each other. and.. they gotta all work together ,and if we dont have the modifiers correct in them, they have a hell of a time.

Anyone have any other info or bulletins on this stuff?

 

Is the 'better' trans fluid that fixes the GM issues spec'd for the 6 speed Ford transmission?
I wouldn't put in any modifiers, just drain, put in a new filter and refill.

How many miles on the truck and when was the transmission serviced last?

 

The shudder is coming from the torque converter clutches. You can usually save the 6R80's by changing the transmission filter. The fluid degrades and clutches start slipping. Feels like going over rumble strips while driving, especially with cruise control set and going up slight inclines on the interstate as the converter unlocks and relocks

 

Exactly. I had an intermittent shudder when I bought my 2015 at 107,000 miles. Transmission oil changed and no shudder since. Now have put 15k on the truck with no problems

 

I have no acceleration shudders. just that shudder feeling while letting off the throttle.

It shifts really good. And the friction modifer seems to have made it feel better driving, but the vibration didn't go away while letting off the throttle.
It did have a bit of a vibration with normal driving before the modifier.

Maybe I do have a bad u-joint too. joy.

Truck has 200k on it.

It's tough chasing vibrations as there can be more variables.
I might have some tire issues too. who knows. Just trying to make sure I don't break anything.

As for the mobile 1 atf stuff.
It had to do with the clutches on those transmissions too. It's not GM specced specifically.
But I have to look into it more.


Anything else I really should look into?

 

I have taken exceptional care of my trans from day one, with multiple fluid and filter changes and I'm at 104K now. I recently tried the Shudder Fix in the red tube just for fun as I have always had a very minor vibration I could never put my finger on since the truck was almost new. And sure enough, after adding the shudder fix the vibration was gone within 5 miles. So in my experience, the mysterious vibration from the trans has nothing to do with how fresh the fluid is. I think the Mercon LV just fails to make this trans happy. I have read great things about Amsoil Signature ATF (blue cap) and one day I am going swap that in and run that for a while without the shudder fix and see if that cures it for me like it has for others. Incidentally, I have a low mileage 4Runner that is now experiencing the same type of vibration at 28K as well. I am now partially convinced these low viscosity lubes are nothing but problems designed to get you back in the shop for bogus big $$$$$ repairs. At 200K, your truck may very well have other issues to sort out, but if I had your truck, I would do 2 drain and fills with a new filter and Amsoil ATF and bit of driving in between, then add the shudder fix afterwards and see what happens. This will leave a few quarts of the mercon LV left in there, and the short story on that is that's a good thing. If that doesn't help, maybe the TC is tired out, or you have other drivetrain vibes as well. Good luck..

 

Just to note in here.

Dash showing me 190 on the trans temp now.

I wanna say it was higher before the friction modifier. but I forgot to check it as I forgot it had a trans temp read out. But I wanna say I was getting 230 on trans temp when I drove it home from michigan. Can't say for sure though because.. I didn't make a mental note.

Whats the safe trans temp range on these?

Also, if I was at 200 or a bit more and i'm sitting at 190 with highway speeds now, that means there was slippage.

 

Weird weird.

One day of driving, 140-160 on trans temp.

Yesterday put some weight in, and it climbed up to 180something.

I'd definitely guess something in there is slipping despite it not feeling like it. As I don't know standards for the trans temps people see that have healthy transmissions, I can only guess at this.
But I do believe the friction modifier helped, even if I still have what feels like the TQ vibration.

So, def changing out the ATF soon.

 

"Normal" is usually around 200 plus or minus 10 degrees. If towing or climbing it will go higher, and is considered OK to go as high as 230-240.

So, depending on how far/fast you're going, yours is running on the cool side.

 

Okay, thats' good info then, because if there is major slipping going on, then the heat is a great way to tell whats up.

So, since I'm doing good on my temps with the 170's, then I know for sure its not a slipping issue.

Now, just to get the fulid changed to see if the rumble goes away on slow down.
It's bad too, which really confuses me because its not doing the shutter any other time that I can tell.
And its tough to tell too, because road stuff and tires and all that.

And the part that I also find fascinating about the shutter stuff is that you get the shutter in neutral still, why would it be acting like its dragging a load and slipping and shuttering if you're in neutral???

 

The GM shudder fix fluid is Mobil1 HPLV with a blue label. Dextron VI had some affinity to absorb water and a triple drain and fill with HPLV was the "fix". HPLV is not Mercon LV certified, but there is overlap in Mercon LV and Dextron VI universal fluids. I have had HPLV in my '15 2.7 Ford for about 10,000 miles with no issues, and I hope that the fluid lasts better than Mecron LV which looks like used motor oil after miles. HPLV is pretty expensive! Personally I'd do a Dorman pan with a drain and a filter, and drain and fill it three times with Mercon LV in 10,000 miles and then every 30,000 miles( about 8 quarts for a drain and fill). It takes about 10 minutes with the drain and filling it with a bucket pump. Put about 5 quarts in, start the truck, and set the fluid level. Reset the transmission adaptive tables with every fluid change. As said earlier, 195F-215F is pretty common at fully warmed up at expressway speeds, empty.

If its doing it in neutral, I'd doubt it's TC shudder. My truck felt like rumble strips while accelerating lightly.

 

Shudder on deceleration and in neutral doesn’t sound like TC issues. Front end alignment or tire wear issues or maybe something with the driveshaft balance might be a consideration to look into.

 

Front end "should" be good.
Just replaced the tie-rod end and got an alignment.

Motor mount maybe?? that really doesn't make sense though as its only on deceleration in drive or neutral.

Being a manual guy, my u-joint feel it out .... uhh... .. whatever you know what I mean. I'm used to how to figure it otu with a clutch. I don't know if there is enough drag in neutral on an automatic to make it do the annoying **** u-joints do.

I was thinking about it being out of balance tires, but you'd feel that all the time.
And just choppy tires usually don't feel like that.

I guess I should front to back them then and find out. It just sounds/feels like everything described with the TQ shudder issue. And I thought I read you'd feel it speeding up or slowing down.

 

my truck was intermittent at speeds above 45. Very noticeable when on cruse control it would feel like you were running over rumble strips or the motor was having a slight misfire. Weird vibration from seat and steering wheel. Ford originally said it was my tires but I was not convinced so I decided to do a transmission service as it was a new to me truck and had 107,000 miles. I didn’t know what services were done. According to the service guy my trans oil was in bad condition. I think the service spec of 100,000 miles is extreme and like many will be changing much more frequently. Tire rotation works to see if the vibration changes as you could have a bent rim or out of balance tire according to the dealer. Good luck and keep us posted when you find a cure.

 

Not familiar with this one.




Checked driveshaft and TQ the other day, More backlash in the TQ than I think there should be, but I have no point of reference.
Changed TQ Fluid because I couldn't feel any when I checked it.
It had 1qt in it. so... ugh. Its full now proper after a change.
I had a random thought that the TQ chain might be in there slapping around, but I don't think that is the case. It's probably fine. Though shortened lifespan running 1/3rd low on fluid for however long.

So, Gonna do a trans flush still. I'll just do the recommended ford stuff with the filter. Can't wait to get oil everywhere, cause.. Automatic transmissions. **** drain plugs. never understood that ****. And the fluid check/fill. Holy ****. It's almost more worth the money to buy the dip stick adapter thing so you can stand and pour from up top.

Only other thought I have here is that its a coil/spark issue.
This is one of the main reasons I have never looked back at Gas vehicles and been like "Wow, I want that again."
If one of those coil packs is a bit weak or someone put the wrong plugs in it at one time. It might seem fine driving, but get all sorts of other weird issues.
It idles pretty smooth overall, but talking with a mechanic about it, apparently its really hard to diagnose missfire issues with a scan tool on these. And they have had problems with not using motorcraft plugs in the vehicles they service there.

I'm not going to say its not doing anything on acceleration or slight acceleration. Cause... Well at this point I'm paranoid.
But the issue is definitely on deceleration where the drivetrain load on deceleration.
But I do feel like I'm getting weird vibrations here and there moving forwards, but nothing near as bad as "rumble strips"