NP 208 Transfer Case

[vangremlin]

I found a 1982 J20 pickup in the junkyard today.  It has an NP 208 transfer case.  Based on this website

http://www.novak-adapt.com/knowledge/np2xx_early.htm

it sounds like the 208 is a forerunner of the 228 and 229.  I'm pretty sure this truck had an automatic transmission, so I think it should have 23 splines like the Eagles.  Do you think this would work for a swap into my Eagle?  Not that I really need it, but I always like to have things to do on my future project list lol.  Thanks!!

[IowaEagle]

Transfer case guide

http://www.n0kfb.org/homepage/amc/tech/transfer_case/swap/

[vangremlin]

Thanks IE.  The article you linked doesn't specfically reference the 208 TC.  I reading the link I referenced, it sounds like the 208 wasa a predecessor to the 229, and operated like this:

"It featured the classic 2wd direct drive in High range and locked four-wheel-drive operation in both High and Low ranges."

The 229 is described:

"The NP229 was similar to the NP228, but it featured an internal viscous coupling for full-time operation."

So it sounds like the 229 would provide better driveability, since you could leave it in 4WD all the time, whereas with the locked 4WD on the 208 is not as desirable??

[eaglefreek]

NP208 is a good case but it is part time plus I believe you will have to do some work to your driveshafts. A 229 or 228 would be your best bet. But, honestly, I don't think you'll ever take Pepe off road and I don't see what benefit low range would be on  a street vehicle.

[rollguy]

NP208 is a good case but it is part time plus I believe you will have to do some work to your driveshafts. A 229 or 228 would be your best bet. But, honestly, I don't think you'll ever take Pepe off road and I don't see what benefit low range would be on  a street vehicle.

If you do take Pepe off road, it may end up looking like my SX4, and WE don't want that....Rich

[vangremlin]

Yea, you guys are right, I won't be doing a lot of off-roading in Pepe.  I guess I'll have to find another project to take on.

[1985amceagle]

the only time i would like low range is in deep snow. i would like to find a full time case as having a part time case in an eagle almost defeats the idea of the eagle. i like the abbility to shift the transfer case and forget it.

[captspillane]

The NP208 was the older version of the part time NP231 in the same way the 229 was the older version of the full time 249. Historically the NP208 was available as an option to Full Size Jeep buyers before the 229, but that doesn't mean one was an older design of the other. The first AMC Eagles had 219s even before FSJs were sold with NP208s. They also continued to offer the NP208 behind FSJ's with the manual transmission after the upscale wagoneers started to come standard with automatics and full time cases.

There are Jeep guys who consider the 231 an upgrade to the 242 because they think part time cases are stronger and because the XJ and ZJ front axles create nasty steering feedback when on dry roads and 4WD. For us Eagle owners driving a true All Wheel Drive car, it would be silly to install a 231 or 208 unless we have a solid axle swap like Regalwizard's old wagon. She liked her 208, but she was using the car to run differently and her front axle was dramatically different than stock.

The 242 is a great swap for an Eagle going to be used offroad occasionally. It gives you a capable open differential AWD that you can leave on. With any decent speed you can give some brake resistance and torque will transfer evenly where you want it. At slow speed you have a locked 4high and 4low that takes out the slip and makes for much better performance than a limited slip transfer case.

For a primarily on-road Eagle the best swap would be a 249 or even better a 247. Those are the improved version of the Eagle system. It is a limited slip differential that doesn't work too well in very slow and very slippery conditions like the locked mode of the 242, but it does work a little bit better at speed than the 242s full time mode. The 249 is still an obsolete viscous coupling design, and it was replaced by the 247 that works better and faster in every category. Both have locked low ranges except for the first years of 249s, which are open differentials in low range and should be avoided.

The 249 and 247 work well offroad too, but I wouldn't use them in a car you intend to offroad occasionally because the limited slips wear out and are expensive to replace. They don't make viscous fluid anymore because it is toxic, so the only 249 couplers available are New Old Stock costing about $250 now.  The 249 cannot put power to the wheels when the viscous coupling wears out.

[carnuck]

The NP208 was the older version of the part time NP231 in the same way the 229 was the older version of the full time 249. Historically the NP208 was available as an option to Full Size Jeep buyers before the 229, but that doesn't mean one was an older design of the other. The first AMC Eagles had 219s even before FSJs were sold with NP208s. They also continued to offer the NP208 behind FSJ's with the manual transmission after the upscale wagoneers started to come standard with automatics and full time cases.

There are Jeep guys who consider the 231 an upgrade to the 242 because they think part time cases are stronger and because the XJ and ZJ front axles create nasty steering feedback when on dry roads and 4WD. For us Eagle owners driving a true All Wheel Drive car, it would be silly to install a 231 or 208 unless we have a solid axle swap like Regalwizard's old wagon. She liked her 208, but she was using the car to run differently and her front axle was dramatically different than stock.

The 242 is a great swap for an Eagle going to be used offroad occasionally. It gives you a capable open differential AWD that you can leave on. With any decent speed you can give some brake resistance and torque will transfer evenly where you want it. At slow speed you have a locked 4high and 4low that takes out the slip and makes for much better performance than a limited slip transfer case.

For a primarily on-road Eagle the best swap would be a 249 or even better a 247. Those are the improved version of the Eagle system. It is a limited slip differential that doesn't work too well in very slow and very slippery conditions like the locked mode of the 242, but it does work a little bit better at speed than the 242s full time mode. The 249 is still an obsolete viscous coupling design, and it was replaced by the 247 that works better and faster in every category. Both have locked low ranges except for the first years of 249s, which are open differentials in low range and should be avoided.

The 249 and 247 work well offroad too, but I wouldn't use them in a car you intend to offroad occasionally because the limited slips wear out and are expensive to replace. They don't make viscous fluid anymore because it is toxic, so the only 249 couplers available are New Old Stock costing about $250 now.  The 249 cannot put power to the wheels when the viscous coupling wears out.

Okay, now I'm getting confused (and I know these tcases quite well)

Timeline: FSJs 80-82 came with NP219 (Quadratrack, but not the Borg Warner version. IFSJA guys call it a Quasi-trak)  or NP208 (Commandtrac)
                           83-88 option NP208
                           83-91 NP229 except '86ish when they used NP228 (both are Selectrac)

Timeline: Eagles 80-82 NP119 aka AWD (really single speed version of Quasi-trak)
                                83-88 NP129 with NP128 '86ish Selectrac.

No Commandtrac version for Eagles, but CJ10A tugs had a NP108 which was locked in low range. (with Nissan SD33 diesel and 727 trans)


PS: I have a NP219 for sale. (and a 401 for $750, and maybe a 727) Also have some used NP129 viscous couplers for $50 apiece. (I guess I need to post an ad, huh?)

[captspillane]

Your list is accurate except for the NP208. It was an option starting in 1980 and stayed until 1987. My 1980 J10 has the NP208.

The NP208 was the older version of the part time NP231 in the same way the 229 was the older version of the full time 249. If you got "Command-trac" in 1980 it was an NP208 and if you got "Command-trac" in an XJ, starting in 1984, it was the NP231. The "Quadra-trac" option in 1980 was the 219, which eventually became the "Quadra-trac" 249 in 1993. The term "Selec-trac" was the 229 to become the 242.

[carnuck]

Actually, I broke it up. I listed the NP208 and NP219 as options '80-82, then NP208 as an option till '88 (I know of 2 '88 J20s and both are NP208)

There was also NP207 '84 to '87 in the XJs and MJs in '86 which was little brother of the NP208. (TOO WEAK!)