NP231 question

[jeff788]

Hey all, just a quick quesiton that I should know but can't remember. Does the chain in the NP231 t-case spin when in 2wd? It seems like it would have to to allow you to shift into 4-hi while still moving, but I can't remember from last time I had it apart. Also, what are some common symptoms of a stretched chain?

Thanks,
Jeff

 

[Herzog]

although it is disengaged, you will get some spin out of the chain just from plain ol' friction. It's been a very long time since I've had to mess with chain t-cases, but you can usually hear a scraping sound in the bottom of the t-case and / or loud popping when the chain slips in 4wd.

 

[bretto]

Yes it will spin as long as the front driveshaft is spinning. The chain is directly on the sprocket for the front output yoke. No drive shaft, no spinning chain.
Brett

 

[4x4phil]

Yes. It spins with the front drive shaft on the dana 30 with the one piece axle to allow you to pull the transfercase into 4wd while you're in motion. Otherwise it would just grind because the gear speeds didn't match and it isn't like the 231 has syncros. And no. The chain wouldn't turn if you had some sort of hub in the front or the two piece axle, accept for some roll just from friction. Also, on a loose chain you hear a pretty loud pop sound when it slips under pressure. It's very noticeable and kinda scary. Whenever you hear a noise like that you always think...oh crap what did it break now, sure hope I can make it home. I had a wagoneer that did that. So basically, what the other two guys said was exactly right, and so were you.