my 90 190 E 2.6 does this and I haven't been able to find help on it. mine does it 25mph to 35mph only in third gear. It doesn't do it if I drop into 1st than manually shift up. If anyone or you pjtib know what causes this please post it.
One tech drove it and said live with it. He thought it maybe excess play in the driveshaft splines.
90 190 E 2.6 162K
91 300 E 117K
90 Laser RS turbo 169K
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