Is there any place where I can either watch or download season 4 of KL? I have looked what seems like everywhere online for it and have just had no luck what so ever.

According to Warner Bros. only the first two seasons of Knots Landing (https://www.google.com/search?biw=1600&bih=763&tbm=vid&ei=oReGW9ipHYi_jgTFyLDYCA&q=Knots+Landing+episodes&oq=Knots+Landing+episodes&gs_l=psy-ab.3..0l4j0i8i30k1l5.574.1478.0.1673.9.7.0.0.0.0.237.824.0j2j2.4.0....0...1c.1.64.psy-ab..5.4.822....0.ebg-Hw4oLIY) have been officially released on DVD (https://www.quora.com/Why-hasnt-the-complete-Knots-Landing-tv-series-been-released-on-DVD) to date because there are heavy music clearance costs (http://www.virginislandsdailynews.com/why-songs-can-keep-studios-from-releasing-dvds-of-old/article_13b0c117-41a5-536b-8908-8355c514949b.html) involved.

If you have a firestick it’s available on there

If you have a firestick it’s available on there

Someone took the time to eliminate the commercials and make DVDs of the 14 seasons.

https://boxset.com/knots-landing-boxset/?gclid=EAIaIQobChMIpqHV3MnC3wIVk1uGCh0GWwCNEAMYASAAEgKUS_D_BwE

Almost entire series is uploaded on Dailymotion (https://www.dailymotion.com/search/knots%20landing/videos).