1995 F150 XLT 4X4 78,000 miles - Ford dealership is not able to diagnose/fix shutter - vibration that became obvious after ball joints, radius arm bushings, shocks, rotors, brakes, tires replaced. Transmission has been serviced and entire fluid replaced with Mercon 5. The shutter is intermittent (3 - 5 seconds at a time) and most obvious between 35 - 40 mph but does not change with increase or decrease in speed or with/without overdrive engaged. The frequency does not seem to change with a change in speed. They think it has something to do with the transmission but I am skeptical. The U-joints have been inspected but not replaced. Any ideas would be greatly appreciated. Thanks.

 

I have a 94 f150 4x2 and my truck has the same identical problem as yours, i to have replaced almost as much as you and still get the problem, also shakes a little going into overdrive my best guess is its either the trans itself or the dang sensor on it i've determined i don't have enough for a new trans so ill drive mine until it just don't shift then fix it lol. If you get yours fixed let me know what the problem is

 

Sounds like torque converter shudder to me.
Alan

 

Shudder is real common i see it alot working at a transmission shop. What seems to be the best fix that we have found is a tube of instant shudder fix. I believe that it's made by Dr. tranny or lube gard. It seems to work about 95% of the time. I know we sell it for $8 so your not out much it doesn't work. Tim

 

Or you can service it and put merconV fluid.
More expensive, yes. The correct way to do it, definately.
I don't mean to be a critic I just don't believe in magic in a tube.
Alan

 

My friend had a similar problem with his 98 f-150.

The drive shaft was out of ballance and the vibration eventualy damaged the rear output bearing on the trany.

When the problem hit critical, his girlfriend was driving it. The trany fluid started leaking out the back, but she kept on driving, dispite the loud noises and check engine light.

The problem was resolved with a new trany and drive shaft.

 

I had the same problem with my 96 with 84K. Mercon V and Shutter Fix by Lube Guard and new filter. My tranny shop said it was great stuff and they use it all the time. Recommended it very highly. The shudder is coming form the torque converter or it was on mine. If it gets bad enough it will kick codes ( torque converter slippage). I took my 93 4+4 to a Ford dealer with the same trouble. The service manager came and told me I needed a new trans at the tune of $2,900.00. I ask him what the data was when they tested it and he said torque C slippage. I drove it home and ordered a converter for it for $250.00 and replace it myself. When I pulled it down it had been replaced with a 99 model year out of a J yard. The only thing I could figure is they didn't replace the converter. Just a thought and don't believe everything the dealers say. Get a second opinion and hope for the best. Hope this help in some way.
F96XLT

 

My girlfriend's '97 Mustang does the same thing.

Same problem?

 

yep same transmission with the same problems

 

You can say what you want about most additives and i will agree but im telling you for $8 theres no beating instant shudder fix. Tim

 

Lincoln MKVIII with the 4R70W did the same thing. A common problem and I agree with Dirtyd0g: fix the problem; you won't be disappointed.

 

I used a 1/2 tube in my new 2003 F150 after the dealer couldn't do much with it. The shudder is all but gone. This fluid is a friction modifier, nothing more. I believe Ford has made their TC friction material very sensitive to shudder, (maybe to improve MPG) that is one of the reasons, (and internal heat) I believe they went to Mercon V.

I would use only enough to help the shudder go away, add a 1/4 tube at a time and then drive it for a week, add the remainder if necessary.

Hope it works for you too!

 

Mine is a '93 F-150 XLT super cab with 207K miles and had the same problem as yours untill my mechanic repaced the shaft yoke (just the yoke, not the whole shaft), an guess what?? the problem is now gone and it runs nice smooth. all for about $50 dlls.

 

You DO know that this thread is 6 years old?

 

just because it's old doesn't mean it's useless i found it very helpful.