Stutter Shudder Vibration 97 Grand Marquis

[FTOSM]

I have a 97 GM LS, 62K miles, runs great overall but during acceleration I was getting this weird vibration for a few seconds in the 30-40 mph range, mostly I just felt it in the wheel but it was noticable.

I searched google and found this article

http://www.alldata.com/techtips/1998/19981228a.html

So I figured why not try it, since i bought the car used and don't even know if they ever did a trans service in the last 59K so I went and got a 95% evac flush done to the system, within the first 2 blocks of leaving the shop it happened once more, yet for the rest of the 15 min ride home it was fine...

Wondered has anyone else done this trans service and did it fix the problem??? (or what else should I look for).

Before taking it in I was noticing it on almost every acceleration... yet after the job being done I did feel it once pulling out into traffic leaving the shop yet it seemed fine the rest of the way home (so far).

Anything else it could be or that I should have looked at or adjusted?


I guess tomorrow when I do some errands I will know more from just driving it around more, I hope the problem is solved...

Bill

[fredjacksonsan]

It may be -- with a 95% flush, the remaining 5% could have been causing the problem. Definitely worth driving for a few days to see if it'll work itself out.

[FTOSM]

Sad to report I drove it around about 15 miles today and still had the vibration thing happening, altho maybe who knows that 5% may still need to get mixed in well with the 95% new and it may "cure" itself or maybe a part in there is "coated" with the old stuff and needs time to wear off (heck I dunno), at least I know my trans flush is done (saw old fluid it was nasty and separated, almost a water like substance on top layer and all dark dark red below, the stuff they put in was bright and new looking, maybe I will do another trans flush after 5 or 10K just to help clear it out more and maybe a bit more around town driving or expressway even might get the juices flowing enough to solve it.

I also remember reading something about a Ford additive that helps this? Can anyone point me in the right direction as to what that is - if it exists...

Lastly for anyone who had this problem and got a trans flush, did it just "FIX" the problem immediately or did it take a few miles on the car to fully clear it up, (I would swear it has lessened in intensity but that could just be my mind playing tricks).

I know this one sat alot undriven at times for a while, so that is whats making me think certain parts may have been soaking in bad fluid for a while and or might be partially "coated" or something, so for now my hopes are the trans service and a bit more regular driving might help it just "go away" on its own...

Bill

[fredjacksonsan]

You're making sense, if there was water in the fluid, driving for another couple thou and changing again will give you an indication of how things are. Seems it takes a bit for stuff to circulate and make a change (if a change is going to happen.

Sorry but I don't know about a Ford trans additive.

[auto trainy]

Why not just change the fluid again? Or have the trans shop road test it and see if it will happen to them.

[paranoidjack]

i have the same problem. I was hoping it wasn't that serious but I guess I was wrong. Does this mean the tranny is doomed, or a rebuild is coming?

[FTOSM]

What happened in my case was that shutter was apparent, I got the trans serviced (full flush) and at first it seemed to still be there (first 30 miles or so) and I then added what ford called "friction modifier" from their service dept (was like $6 for a 4oz bottle) added 2 oz's of it and then I took the car on a road trip of aprox 300 miles mostly expressway and when we got home driving around the city again I noticed the problem had gone away.

Was it the friction modifier or the trip and working that fluid thru the trans, or a combination of both or just dumb luck? I dunno but the problem is gone and it was alot cheaper than having the torque converter replaced...

So until it rears its ugly head again (hopefully not for a long time) I have found a solution to this one...

Bill