1995 Ford Thunderbird Power train shudder

Tiny
LAZYBONES1222
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  • 1995 FORD THUNDERBIRD
  • V8
  • 2WD
  • AUTOMATIC
  • 79,000 MILES
Car shudders under 1500 rpm when slight acceleration is added by gently depressing gas pedal. Seems to be a drive line shudder. If I push harder on the gas pedal it goes away. I have read elsewhere it may be a PCM prgramming issue. Any thoughts?
Monday, October 18th, 2010 AT 5:20 PM

13 Replies

Tiny
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Thoughts I am leaning to are u-joint or misfire.
If it is driveline, pcm update will not help.

Does it seem consistant as certain speeds?

If you brake rev it does it break up?
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Monday, October 18th, 2010 AT 6:30 PM
Tiny
LAZYBONES1222
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The car had a tune up and new wires at a dealership less than 2 years ago - the engine never seems to misfire, it only is shuddering at very low rpms when you egg shell the throttle - you know baby it. If I put my foot in it everything is happy or accelerate swiftly. But I like to baby the car to save gas - then it bucks between 1100 to 1500 rpm at around 30-45 mph. It is only when I really baby it in drive or overdrive it shudders. Weird. At first I though it was a fuel injector issue but I have run two bottles of seafoam thru it to no avail. I cleaned the Mass air flow sensor too. Could it be a fuel injector thing? Also, I read somewhere it may be the torque converter - is the torque converter in the 95 tbird controlled by the PCM?

It does not break up if I brake rev it.
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Monday, October 18th, 2010 AT 8:00 PM
Tiny
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I just love when I spend 20 minutes writing a post and for whatever reason the screen refreshes and I lose everything. Sigh.

Anyways.
I am leaning away from the misfire based on your results. The converter is not controlled by the pcm but there was a different updated one for it that did cause a shudder.

What I would suggest is to completely change the fluid including the torque converter's fluid, replace the filter and add a pint additive of friction modifier.
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Tuesday, October 19th, 2010 AT 5:57 PM
Tiny
LAZYBONES1222
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Different updated what? PCM software or converter? Please clarify.

I really do think it is transmission or converter related - I can feel it through the floor boards. It is definitely not the engine, runs smooth as glass. The transmission was flushed 11-1-08 (I keep receipts for everything).

Is the torque converter fluid separate from the transmission? How do you add to or change the fluid in the torque converter?

Also, what is a friction modifier? Is that something like Lucas Transmission Conditioner?
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Wednesday, October 20th, 2010 AT 10:14 AM
Tiny
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I'm sure there have been updates to the computer, but I was referring to the converter.

We use fluid exchanger to completley change the fluid in the trans and the converter.

Lubegard make a friction modifier that we use. I wouldn't use Lucas in this situation.

I would also change the filter.
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Wednesday, October 20th, 2010 AT 3:34 PM
Tiny
LAZYBONES1222
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Thanks for your help guiding me in the right direction. This is exactly my problem, here is the Ford service bulletin for it. Florida is tough on these transmissions, may need to get a cooler. Check it out:

http://www.stangnet.com/images/stories/docs/sn95_TSBs/98-08-07.pdf
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Wednesday, October 20th, 2010 AT 7:46 PM
Tiny
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Good chance you are there, but time will tell. Good Luck.
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Wednesday, October 20th, 2010 AT 9:00 PM
Tiny
LAZYBONES1222
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https://www.2carpros.com/forum/automotive_pictures/584303_my_new_car_1.jpg



40th anniversary model in the metal flake green - she is a beauty huh? lol
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Thursday, October 21st, 2010 AT 6:59 PM
Tiny
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Certainly hasn't spent time in Western New York!
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Thursday, October 21st, 2010 AT 7:22 PM
Tiny
LAZYBONES1222
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No - there would be nothing left but rust - Florida car. :)
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Thursday, October 21st, 2010 AT 7:42 PM
Tiny
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Ah contraie. There would be a bunch parts that are starting to rust because they rotted out 8 years ago and were already replaced lol.
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Thursday, October 21st, 2010 AT 7:47 PM
Tiny
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Ok - I will in time replace the fluid and filter even though it was just done two years ago - the Florida heat is real tough on tranny fluid.

But due to my busy schedule and need of the car, I siphoned out 12 oz of transmission fluid then added a 10 oz bottle of LubeGuard ATF Protectant and a 2 oz tube of LubeGuard Dr. Tranny Instant Shudder Fixx.

Results? Shudder is absolutely gone - none - gone - just like magic. LubeGuard products work.

Links for products I used:
http://www.lubegard.com/C-112/LUBEGARD+Automatic+Transmission+Fluid+Protectant

and

http://www.lubegard.com/C-230/Dr.+Tranny+Instant+Shudder+Fixx
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Sunday, October 24th, 2010 AT 8:42 PM
Tiny
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Excellent. Good to hear, thank you for the update!

After 30,000 since your last filter change is when I would change it next.
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Monday, October 25th, 2010 AT 6:43 AM

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