CJ's was available with 3 different powertrains; V8, I6 and a 4cyl. The drive train configuration was a Dana 30 in the front and Model 20 on the rear. The later CJ Versions came out with the Dana 44 rear axles which is known to be much stronger and reliable due to it's one piece , larger axle shaft as opposed to the AMC Model 20 2 piece axle shaft .Also, the AMC 20's has a narrow track(76-81) and wide track(82-86) variation. The suspension is Leaf sprung in the front and rear as opposed to the TJ's coil spring and link suspension. The only Electronic controlled engine component on the CJ5 and CJ7's is the ignition system which is a Ford ignition module that can easily be eliminated by replacing the distributor with an HEI system. The TJ production started in late 96 and it's debut in 97. Early productions used some components off of the YJ's and re-tooled the production line as they progressed on with the build of the TJ's. Prior to the TJ Unlimited (Long Wheel Base ) , the body dimensions between the CJ,YJ and TJ's are pretty much the same with the windshield frame as an exemption. The wheel well on the rear found on the TJ's are more refined than the square bulky one's found on the CJ. The TJ's instrument panel was one of the biggest changes. Mostly plastic molded panels with a more sophisticated electronic instrumentation. The cluster in itself is a module as opposed to the prior models with Gauges that's called nothing BUT a gauge. TJ's are available with a I6 cyl and a 2.5 4 cyl computer controlled powertrain and partial drivetrain if it's an automatic. It's suspension is much more a comfortable ride than the CJ's but i really don't think it bothers me much or if it does at all. The fuel delivery system on the TJ's are fuel injection as opposed to the Carburated CJ's. Fuel injection systems has proven itself to be more efficient and reliable than the carburated CJ's . A noticable difference on the front grill and hood between the CJ and the TJ is that the CJ's are a lot taller than the TJ's profile. I Hope this answered a few of your questions.