Hi, I noticed a jerk between 120 - 140 while speeding with full throttle. But on normal throttle if I goes 120 - 140..No jerk. Oil is nice and red without any burning smell...but there were some bubbles on the dip stick.

Any ideas why jerk..or I let it go as normal

Thanks.

 

I'll assume those speed are km/h
Bubbles on the dipstick could be because it's been over-filled or it's running hot. Could also be the torque converter starting to fail which is causing the "jerk."

 

Disco2 you made me laugh as well...you are right it is KM/H