A/T Shudder during 3rd to 4th gear shift...

[Dennis C.]

... OK, first must admit this has to do with my wife's '93 FxxD Exploder...
Started getting a noticeable shudder between 3rd & 4th gear at about 40K miles. Flushed trans fluid - got quite better for about 5K+ miles and then returned. My tranny guy says we need a new torque converter to fix the problem. The shudder drives me nuts, but otherwise, the transmission seems to operate just fine. I am begging for a few learned 2nd opinions. Thanks, Dennis

[Mike McKown]

Re: A/T Shudder during 3rd to 4th gear shift...

The wife had a new '92 Crown Vic that started doing this at about the same milage. I changed the plug wires and the problem went away. I have a '97 T-Bird that has been doing this since almost new. Still does it at 40,000 miles. It's no worse than when new. It's running fine except for this. It ain't broke so I'm leaving the hood shut!

You may have a different problem but an experienced transmission man should know if it's a transmission problem. It's the 3-4 shift, not the converter lockup. I think all three of these vehicles have the A4LD transmission but I really don't remember.

[David M.]

Re: A/T Shudder during 3rd to 4th gear shift...

The clutch is shot in the converters lock up function. Get a new converter (or have yours rebuilt) installed before it sends anymore trash through the trans. Do a complete power flush and filter change, not just the "drop the pan and filter" thing.

[Joel A.]

Re: A/T Shudder during 3rd to 4th gear shift...

The lock-up clutch in the torque convertor will only create a "shudder" on application, not before, not after. If the shudder is occuring during the 3-4 shift, it is not a tc problem, but most likely a problem with the O/D band, or O/D servo. The servos in these units(A4LD/4R44E/5R44E) have a tendency to get hard, and crack the rubber on them. They are very close to the exhaust on these vehicles, and that's what does the most damage.
If it were in my shop, we would adjust the O/D band first, to see if the "shudder" changed, or went away.
Just an opinion...

[Dennis C.]

Joel, Yes, occurs exactly (and only) during shift *NM*

[Joel A.]

Re: A/T Shudder during 3rd to 4th gear shift...

Mike, the Crown Vic will have an AOD-E trans, the Turd-bird will have the 4R70W, basically the same unit, with different gear ratios.
All Exploders came with the A4LD/4R44E/5R44E units. These three are pretty much the same, with the "E" units being electronic controlled, and the 5R44E having a higher torque rating.
Later Exploders have a 5R55W/S/N type unit, which are all 5 speeds.

[Dennis C.]

Thanks all for guidance... Will add that we...

...bought a 2006 GMC Duramax/Allison 3/4 ton pickup. So far, I do believe that 6 speed auto transmission was made in heaven. Additionally, its a heck of a lot smarter than I am...