I did the swap to Mercon V (including TC) a good while back to cure the original shudder, as per the TSB. That fixed it for a while. Then micro shudder (more subdued than the original) began and when I called a tranny shop, the owner was reluctant to do another fluid change (I couldn't do it myself for various reasons at the time) and instead recommended I try a friction modifier. That helped for a while.
The shudder eventually returned and became more pronounced in short order. I noticed the fluid level was a tad low, so I topped it off and NOW I'm getting random tranny hop (pulsing).
Shift points are normal, there doesn't seem to be any lag or other anomalies, it just pulsates (intermittent slip) after a gear has engaged (yes, shudder during engagement and pulsing the rest of the time).
It occurs regardless of speed or gear. It's also inconsistent with acceleration -- sometimes I can punch it and there will be no pulsing; other times there will be a major effect; same goes for casual acceleration.
If I back off on the accelerator, the pulsations stop and often don't return when I again apply pedal (gingerly).
It usually, but not always, occurs after the tranny has reached nominal operating temp.
Is this likely a case of the Castrol Mercon V breaking down, losing its viscosity already or am I looking at more involved problem$ like friction plates? I suspect the fluid, but I suppose the friction plates could be acting up only after they warm up -- but wouldn't they be more likely to produce prolonged and consistent slippage?
Also, I did not perform a flush
at the TSB change, I just drained the tranny (unplugged TC and yanked the pan). I know if there's old non-V fluid left it can cause shudder to return, but this more severe pulsing effect? I did not pull the VB
, either; would enough fluid remain in the VB
to lead to this?
I've purchased enough Motorcraft Mercon V for a system refill and a new Fram filter, but I would hate to see that $75+ in fluid gone to waste if it won't fix me up.
So, would you recommend the fluid/filter change or should I hold the material in my personal inventory and head straight to a tranny $hop instead for a thorough flush and/or who knows what else?
FWIW, I've done an overhaul before (on a different make), and I'm a consumer electronics tech for 25+ years, so I'm comfortable around servo-mechanisms.
However, this is my DD and it's my only transportation ATM; I can't be out a car for the length of time it'd take me to do major work on it, if I could even manage to safely drop the whole tranny on my own -- I also don't have a flush machine.
edit: forgot to mention this tranny has 83,800 miles on it..