I have a 1990 Chevrolet Blazer 5.7L 350 HP it's a 1/2 ton 4WD automatic.Question:  i have the 700r4 to the NP208, and the last time we went wheeling, I locked in to 4wd and when its engaged, and u try to drive forward it feels like its binding up and then if u go a little further it pops and it releases tension till it spins a few more times and does the same thing in reverse, i CHANGED THE fluid in it and it was clean, no metal chunks but i noticed a piece was sitting in the bottom by the drain plug, and thought maybe it was the magnet but not sure asked a few shops and they said the chain might have stretched out and folded over a link and when that link gets to the tooth it binds up. any help would be nice because i like the 208 and 700r4 but want to know of a rebuild kit or if i can get a built one for off road use, like mudding or rock crawling something strong like the 205.Answer:   Unfortunately the NP208 is a little weak for off roading. There isn’t any way to build it to be strong like a gear driven NP205We can offer parts or a rebuilt NP208 or you could upgrade to a NP205I am confident you have a chain problem in your NP208, you will see below.. price on a rebuilt and core charge then below that a gasket and seal kit and the HD chain

Chevrolet Pickup 27 Spline 81-88 MWTTCGM013 $800.00

Core Charge on Transfer Case $250.00

N.I. Gasket & Seal Kit TSK208 $25.95

43 Chain (1.25” Wide) 36 Links (Round Pins) (Dodge, GM) MWTCL10-025 $100.33

 The other option is a 27 spline NP205 with the adapter and coupler for $1100.00 but you will have driveshaft mods and have to buy a new shifter assembly for the NP205, core charge and freight will be added. Give Scott a call 888-824-2012 he can help you.