92 ex problems, 4x4 rough

[katt68]

the 4x4 works but is noisy as hell when engaged.
i got manual locking hubs which are great. i click the hubs in and the grinding /scraping sounds start. the 4wd works but the noise is scary. without locking in the hubs and pressing the push button 4wd lights up, and no sounds. but it is when i engage the hubs? please advise?

 

[dejello]

My first thought was the hubs, but then you said the 4x4 still works (are you sure they are locking in?). Does it make the sound if you engage the hubs but stay in 2wd? If not, I guess it could be a u-joint in the front driveshaft.

 

[paperjam]

how hard are those u joints to replace and can i get them at a local auto parts store?