I am currently evaluating my father in law's 08 King Ranch Super Crew 4x4 as he is no longer driving. While driving it home I noticed that it would periodically shutter like you were hitting rumble strips at high speed. The more I drove I realized that it was doing it after it down shifted and the torque converter was locking up. That is usually not a good thing, but my question is, does that mean I need a new transmission, or would a fluid change help that?
Also, is there a lockup solenoid in this trans, and could it be getting weak?
This truck has 97,000 miles on it, and I am sure has the original trans fluid in it.
Can anyone tell me what trans would be in this truck?
The fluid smells pretty good and seems to have pretty good color.
Dipstick says use Mercon V fluid.
Could the additive pack/friction modifiers be getting worn out in the fluid and causing the shudder?

Thanks for any and all help. This is my first foray into this model of truck.

 

Are you sure it's not a low grade misfire? If the spark plugs are original I bet that's it.

At 97k, I would get the trans fluid completely exchanged, not just a pan drop. Quick oil change places and others have a machine to do this. You should have a 4R75E.

 

I am guessing the spark plugs are original. I was planning on changing those as well as doing a coolant flush and hoses, since I believe that is also all original.
Wouldn't the misfires throw a code? There are no codes on this truck. It had an ECM put in it about 4 to 5 years ago. I noticed it said Ford Reman on the computer on the firewall.
It shudders after a downshift, and then it shifts back to 4th about when the torque converter would lock up.
Has anyone tried taking the trans cooler lines off and putting the suck side in a bucket of new fluid and the other end in an empty bucket to change all the fluid? Would that even work?

Thanks.

 

No, that fluid change method would not work. The trans pump sucks oil from the pan. The fluid can be changed by dropping the pan and refilling the pan. I'd also change the filter. Then disconnect the line returning fluid to the pan and start the vehicle. After the pan is emptied stop the engine and refill the pan. Do this until the fluid is fresh. There is a better description on how to do this somewhere on this site and I suspect on the youtube videos.

 

This is how it's done:

https://www.f150online.com/forums/tr...id-change.html

4R75E is the same as 4R70W for this purpose - same procedure, same capacity, no torque converter drain plug, use Mercon V.

 

Thanks for the tips, I appreciate your help.

 

Figured I'd throw my 2 cents in since I had this issue about 3 years ago on my 2010, 4.6l 6 speed auto.

I got the same thing and first thing I did was change all the plugs and wires/boots - no change.

It was happening quite regularly when hitting 35-45 mph on acceleration. I heard about Dr. Tranny Instant Shudder fix on a Youtube video where some guy was having a similar issue, so I got a couple tubes. Why not, it's Cheap. I had already sunk a couple hundred bucks in plugs and wires and was desperate.

Well damn if that didn't completely eliminate the shuddering...or at least I didn't get the shuddering except maybe 10% of the time. Since I figured it was a tranny/torque converter issue I figured I'd get the tranny fluid changed. Truck had about 180k on it at the time. I had heard that you shouldn't do that, it'll ruin the engine, blah blah but I said to heck with it. The guys at the dealer even made me sign something where I agreed that doing this fluid change may destroy my transmission.

After the fluid change I never get the shudder and I'm going on about 3 years now and I'm at 205k miles. I think it maybe did it a couple times at the beginning right after the change, but in the past 3 years I never get it. Mind you I'm in the ozarks so I'm going up and down hills all the time changing gears like a mad man.

It's easy to put the tranny fix in just to see if that solves the issue. If it does then you MIGHT want to do the fluid. If not, then just put the tranny fix stuff in and it may solve it.

 

Also don't forget that transmission shutters can also be caused from fuel delivery and combustion problems (spark plugs and/or coils).

 

The 6 speed uses Mercon LV, not Mercon V.

 

Probably the overdrive servo in the transmission case. My 2005 Lariat did the same thing.
Here's a great video on what/how to fix:

 

Merry, that fixes no overdrive, not shudders.

 

GLC, mine did a similar shudder when shifting under medium power around 45mph.
Sounded like the truck was farting or going over rumble strips.
The repair video I posted solved my problem, and I am hopeful it may help the OP.

The retaining ring on the overdrive solenoid is a common failure, and the bits from the ring can clog ports in the valve body and cause shifting issues - not just loss of OD.