I have an 01 SCREW 2WD, 4.6, 82K, tranny requires Mercon V, can't remember what version tranny. I notice a shudder at steady throttle around 40 MPH, or going up a hill at light throttle, or when starting from a stop. When I turn the O/D switch off, these symptoms go away. All fluid changes have been done via flush. I changed the fluid at 36K miles, changed the fluid and filter at 65K miles. Truck currently has 82K miles and the shuddering just started about a week ago (less than 500 miles ago) and has gotten steadily worse.

I have searched this forum for tranny shuddering in overdrive, but none seem to have the same circumstances that I have.

Anyone have a cure?

TIA,

 

It's either torque converter shudder or a light-load misfire.

If indications are that it's the TC, I'd flush the tranny then add a bottle of Lubeguard's Shudder Fix.

If you have a well-capable scanner (the cheaper ones can't do this), look at your misfire count PIDS to see if you're starting to accumulate misfires on one or more cylinders. You can have a certain number before the CEL will be turned on.

Steve

 

You are one of many to experience this phenomena known as torque converter shudder. As soon as I felt my shudder at 40mph, I took it in for a full service flush with Mercon V. It actually make things worse and it started to shudder all throughout the power band in any gear within a week or two. The Dr. Tranny junk everyone said to add just makes everything feel mushy and may mask the feeling of shudder for a short period of time. From what I've read, it's actually the torque converter that is locking/unlocking. Since I have so many miles on the transmission, I feel like getting the TC replaced without rebuilding the clutches is a waste of time. I am in the process of looking for fully rebuilt transmissions, but I will continue to drive it in the meantime.

 

I am now feeling the shudder on my "07" with 62k on it. I think it's odd that I am feeling only after my transmission was flushed. It only seems to do it when I am going up a slight grade and when my speed is just at the point where it wants to downshift. I am glad I found this thread, I thought I was going crazy...just like when my vacuum selenoid for the 4wd was failing and I kept getting this massive clunk when driving down the highway when it was trying to engage my 4wd. You Guys have saved me so far.

 

Whenever I have had torque shudder, a complete change of fluid has always fixed it,not made it worse.

 

SYMPTOMS: I had the same "shudder" symptoms at 60,500 miles on 13 year old 2002 F-150 4-2L V6 with auto trans 4R70W model in Southern Calif. I also noticed it took slightly longer to start than usual...

SOLUTION: I found 2 spark plugs that the metal rod had rusted & come apart - the metal pin just pulled out with the boot about 2 inches long! Anyway, I used lots of dielectric grease on the new ones in case it was moisture getting in there that caused them to corrode. The 2 spark plugs were on the passenger side #'s 2 & 3...

Runs like a champ again :-)

Thank God it was the "light-load misfire!"

 

I have the exact same symptoms!

Does anyone know the fix?

 

Refer to post #2.

 

Hi I just bout an 06 f150 4 x 4. Everything ran great and next day after buying it, it started spudding! I immediately called the car lot I bought the truck from and they saI'd they put new coil packs and a new catalytic converter so it should be fine. I'd advised the the salesmanext that this is uncalled for and would have never bought this truck if this would have happened during my test drive. The salesman then went on to tell me that they don't have a mechanic they use but told me to take it to someone local and call him if they figure what is wrong and said they would only cover the parts. Are you serious? I'm calm but this is putting a real bad taste in my mouth. Any ideas what it might be? It shudders randomly and different speeds. If they aren't willing to pay for this I will either take them to small claims or get my money back

 

Spark plugs and/or coils. Refer to post #2. You need someone with a good OBD2 scanner that knows how to use it.

 

I took my 2006 4X4 Lariat in for a transmission flush in 2013 at 125,000 thousand miles. The truck was running great with no problems before. As soon as I left the shop it had a shudder going up small inclines (even on the interstate going up overpasses). I thought is was something to do with the fluid flush. I traveled out of state on business and had the fluid changed again there in another shop. When I got back to the original shop they diagnosed a coil and also changed the spark plugs. That cured the shudder.

I'm not sure what the shop did to make that shudder start happening in the first place but I felt it within one mile of leaving the shop that day.

Really glad it's fixed now. I put up with it for about 6 months. The truck now has 160000+ on it.


Dennis