The CJ-7 was produced from 1976 until 1986. The CJ-7 is basically a stretched CJ-5. An extra 10" was added behind the front seats to make the CJ-7 a 91" wheel base vehicle vs. the CJ-5s 81". The extra 10" allowed AMC to offer an automatic transmission for the first time in a CJ. A CJ-7 tub can be identified by the shape of the door opening, the opening is square where as the CJ-5 has a curving door opening. The Wrangler (YJ) tub has the same dimensions as the CJ-7 and can be used on a CJ-7 with some modifications.
The CJ-7 also was available with a hard top and doors from the factory. Hard tops and doors were available for earlier models, but not from the factory.
A new fully boxed frame was available for CJs from '76-'86 and although the welds are ugly, the frame is stronger than frames used in previous CJs. The frame was widened in the rear and the springs were moved farther out to make the CJs more stable on the road, unfortunately this mildly reduces the articulation of the rear axle. Other features such as sway bars and steering stablizers were added around this time to increase handling. Another change in 1982 was made to make the CJs more stable, wider axles were used. There are some differences in shock mounting, but "wide track" axles are compatible with '76-'81 "narrow track" CJs and visa-versa.
1980 marked the end of the Great Transmission Era. The '80-'86 CJs used medium and light duty transmissions compared to the heavy duty transmissions available in the late 70s.
1980 marked the return of the I4 CJ with the introduction of the GM 151 engine. 1981 was the last year for the V8 in a CJ from the factory. The 304 V8 was no longer an option from the factory, only the six cylinder and four cylinder engines were available after '81.
Several different trim package were available for the CJ-7s over the years including the Laredo and Jamboree packages. These are typically just trim packages though, they don't add much to the value of the vehicle.
The CJ-7 was originally offered with the 232 I6 as the stock engine and the 258 and 304 as an optional engines. In the late 70s, the 232 was dropped and the 258 became the stock engine. In 1980, the GM 151 I4 I4 engine was stock and the 258 and 304 were optional. The last year for the 304 was 1981. The GM 151 was replaced with the AMC 150 I4 in 1984.
From '76-'79 the T-150 3 speed was the stock transmission and the T-18 4 speed with granny low was optional. During this time, the GM TH400 3 speed automatic was also available. After 1980, the heavy duty transmissions were no longer used. The SR-4 and T-176 were used with the I4 and I6. The T-176 was used with the 304. After 1981, the T-4, T-176, and T-5 5 speed were used. From 1980-1986, the TF999 was used with the I6 and V8 and the TF904 was used with the I4.
The Dana 20 was used from '76-'79 and the Dana 300 was used from '80-'86.
The Dana 30 was always used in the CJ-7.
Some odd models of the CJ-7 used the Dana 44, but the normal axle was the AMC 20.