1988 Mustang possible transmission shuddle?


New Member
Mar 28, 2020
Long Beach
Hey guys, new to the forums. Not too long ago, my car began to buckle under deceleration. 1988 mustang gt AOD. Seems like if I let it coast under 30 to 35, it starts to buckle. At first, i thought it might have been a bad motor mount that was broken and making the engine rock around upon downshifting on itself. After inspecting and looking for obvious signs of a broken engine mount, i determined it wasn't that.

I did some research and most mustang owners who had a similar problem were people with t5 transmissions, sn95s auto transmissions, or bucking on *acceleration*.

The people who had sn95s with automatics apparently had a couple tsb's I believe involving a transmission torque converter shuddle from the factory. Their solution seems to be to flush out the trans fluid for mercon 5 fluid.

Were foxbodies with aod transmissions plagued with the same torque converter shudder? Not sure if buckling and shuddering can be described the same, but upon deceleration, i can feel the buckling on the floor board, like as if the trans was hitting against the trans tunnel. Thank you for any suggestions


Wasn't a pretty sight...and I've got big hands
SN Certified Technician
Mar 2, 2015
On the sn95 it felt like a misfire around 40 to 45mph. Usually felt at light throttle cruise. The crown Victoria's had it too. Speaking from experience.

If its occurring during decel...does it also do it when shifting from drive to reverse ?


The first widely accepted Tranny
15 Year Member
Dec 24, 2003
30 Mins from a Ragged GT
Shudder Stop???? About 35-40 area under normal acceleration my son had the issue and we used this and it helped a whole lot. It would never happen under hard acceleration