How much transmission "shudder" is acceptable? I just had my 4R70W 4WD transmission completely overhauled and installed a remanufactured torque converter from a reputable transmission shop. However, there is still noticeable "shutter" at various speads, rpms, especially at 45-50mph around 1,250 rpm.

My transmission has been bad for a while, so I don't remember what it used to shift like. I understand these trucks don't shift like a Lexus (where you don't feel it shift at all), but how much shutter is normal in an F-150?

Work done per invoice: Install scanner & verify internal fatigue & torque converter failure. Remove my 4R70W 4WD transmission, disassemble, clean & inspect. Overhaul complete. Install hard parts accordingly & re assemble. Fill with new factory specific fluid. Road test. Clear data & verify shift function. Install remanufactured torque converter.

Truck has 91,000 miles

 

You have the symptoms of a low grade misfire, not TC shudder. At 91k you are due for new spark plugs.

 

No shudder is acceptable. Have your spark plugs/ignition coils checked. That's the typical speed that you feel low level misfire, which most people mistake for transmission shudder.

 

Thanks for the input.

 

That also is the speed you feel the TC shudder if the mechanical lockup is slipping. So, find out for sure what it is while you can still take it back to the shop that installed your TC and get them to repair it for free.

 

I brought the truck back to the shop. The guy said the transmission he fixed is fine, but the continued shudder is due to the “coil pack” and needs to be replaced. He said the part is easy to fix, but is labor intensive to get to it.

Should I expect this to be an additional charge or would you expect that it would have been included in the transmission overhaul job? He never mentioned the word “coil pack” when originally discussing job or cost.

Again, work done per original invoice: “Install scanner & verify internal fatigue & torque converter failure. Remove 4R70W 4WD transmission, disassemble, clean & inspect. Overhaul complete. Install hard parts accordingly & re assemble. Fill with new factory specific fluid. Road test. Clear data & verify shift function. Install remanufactured torque converter.”

Thanks in advance for your feedback.

 

It's shudder, not shutter. A shutter covers a window.

The coil pack is on the engine, not the transmission. It's never part of a transmission overhaul. I would expect an additional charge.

Why did you have the trans rebuilt in the first place?

 

The coil packs are part of the ignition system. Refer to Mark's and my previous posts.