I have a 99 escort sedan 5 speed manual transmission. My problem is that when I step on the gas the car shutters. It also shutters when I first let off the gas (ie exiting the hwy). Car has 197K I put new (used)engine and transmission in 20K miles ago. Both engine and transmission had below 50K miles on them when put in. Example of what it does. Car shutters more during heavy acceleration. If I shift thought slow it is not as bad. Worst shutter is when you skip a gear (ie shift from 2nd to 4th). If you step on it in 5th gear (already going 60mph) car shutters, but if you drop to 4th before you step on it not shutter. Notice a small amount of Trans Fluid under car Comming from end cover on tramission I am going to fix that is weekend. I am at a lost. Fluid not low. Could it be bad inner CV joints, or is there a way that Trans Fluid could be leaking onto something and making it slip? Thanks for all your help.

I doubt the CV joints are your problem. The problem seems to me to be in the clutch. It is not properly engaging. This could be to a worn clutch disc or a bad pressure plate. I would check the tranny for proper fluid level but this really shouldn't have anything to do with your problem. (Whoever had the car before you may have abused the clutch.)

You say the new engine and tranny were put in awhile ago... how long have you had this problem?

Make sure all the mounts are good.

You say the new engine and tranny were put in awhile ago... how long have you had this problem?

Make sure all the mounts are good.

Mounts are good. And I started having this problem about 3 weeks ago. Sometimes the car does not do anything and drives fine. Then the next day it will do this all day long.

Just to let everyone know problem was not Trany, CV, or Clutch. I stared the car at night opened the hood I could see the Plug wires arch to block. So all of this and all I had was bad wires. Just a little lesson check the small stuff first.
Thanks to everyone that offered an answer.