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Infinite Knowledge of the np228 Transfercase

Contributed By: Snakeyes_Tx

I will now share to you my infinite knowledge on the drive-line part of an 86 FSJ that originally is equipped with a New Process 228 transfer case. Upon first glance, you would think that the designers were on crack when they made this case but I'll tell you this much. With a little bit of cash and some ingenuity, you can make the axle set-up these came with work fantastic! The front Dana 44 on the FSJ that was used in 1986 was NEITHER an Auto Hub **OR** a Manual Hub. Rather it was a hub that was constantly "locked" and was always spinning. (Technicians note : This axle can easily be made to a manual hub. I left mine constantly locked because my R-&-P is pretty shot already and there's nothing for me to save anyhow) A Direct swap to make these axle work like champs is the New Process 208 transfer-case found on early 80's FSJ's with the manual hubs. If you can get good hubs from a part's rig, then go ahead and get them and put them on. DO NOT forget to lock and unlock them when shifting in and out of gear though (If that is too tedious, leave the hubs alone then). The 208 was a direct bolt-in installation and as much as I didn't like it, the "little metal rod with the black flag" shifter for the 228 worked with the 208 (Technicians note : DO NOT count on the markings on the shifter that used to say 4-HI, Neutral, 4-LOW!!! You can actually feel every gear selection in the 208 and the markings on the stick are not the same). Now that you have the 208 bolted in, you're wondering two things, Why won't my rear drive shaft reach the back of the transfer-case, and what about the vacuum switch? Well, first off, the vacuum switch can be pulled and bolted off now because the case has a 2-HI option. As for the drive shaft, if you put the 208 next to the dropped 228, you'll notice that the 208 is about 5 inches shorter than the 228. 228's had a center differential and of course, you couldn't "lock" it so that would explain why the case SUCKED and was replaced with the 229 of its previous years to the end of production. You will need to get the rear drive shaft lengthened 5 inches. Get a professional to do this, its only about 140 bucks to get done WITH new U-joints and balancing. Okay, now that you have the vacuum lines bolted off, the newly lengthened drive shaft in, and everything bolted up nice and tight, lets fill it up! The 208 runs off ATF from the transmission via 2 lines. (Technicians note : The shift linkage with the little flag should have also been connected to the transfer-case by this time. With the black flag all the way down, the transfer-case is in 2-HI... leave it there till you drive it around at first. Just barely pull up on the lever and you'll feel it click over to 4-HI. Next is Neutral and then all the way up is 4-Low. Remember that you must be rolling a little to go from 4-HI to 4-LOW!!! That never changes in this swap!) Okay with that all out of the way, lets start the rig up and let the fluid run through the system. Let it run for about 30 seconds and then check the transmission fluid via the dip-stick. It will naturally read a lot lower because it pumped a good amount of its fluid into the transfer-case. Refill accordingly. Let it run again for about another 20 seconds and check again. At this time you can hop inside the cab, and drive it around a little bit.  I went around the block and up to about 60 mph to check for vibrations and such. If you have none, then on the street, go ahead and from Neutral on the transmission shift the transfer-case from 2-HI to 4-HI... listen for any noises and if not, give it a little gas and watch it work for you! While rolling 1-2 mph, shift it from Neutral on the transmission to 4-Low on the transfer-case and FEEL the torque difference when you put the transmission back into drive. Notice it lunge forward and backward? Wonder why? Because that 208 has a WAY better crawl ratio than that 228 EVER did. If it works, then go ahead and drop it into 2-hi again and drive around on it for about 50 miles before doing any froadin. Overall, I paid 250 for the case (Thanks FSJeeper!), 140 for the drive shaft lengthening, and a few hours for time. My results? I've been driving about 400 miles on this set-up and I've driven the trails and hills and it works phenomenally! I highly recommend this swap for anyone with an 86 FSJ that can't stand or killed their 228. I went through 3 of them before I went with a 208.

owner of a bullet-proof "Rusty"

Editor Note: The following is a submission from Kris Tholke pointing out some differences of opinion he had and some errors regarding the above article, they may be helpfull to you.

1. "The 208 runs off ATF from the transmission via 2 lines."
The NP208 DOES NOT share lubricant with the transmission. It is just like every other New Process, aluminum cased, chain driven transfer case. It has a drain plug and a fill plug, and there are no " lines" except a breather.

2. "...Because that 208 has a WAY better crawl ratio than that 228 ever had."
The ratio in my 228 (as it sits on my garage floor) 2.61:1 The ratio in my 208 (as it sits in my wagon) 2.61:1

3. "...the vacuum switch can bepulled and bolted off now because the case has a 2-HI option."
My 228 had 2 hi. (?)

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