Review on 🚗 Hikotor 4WD Wheel Drive Switch Replacement | 4x4 Transfer Case Dash Selector for Cadillac Escalade, Chevy Silverado, Chevrolet Suburban, Avalanche, Tahoe, GMC Yukon | Compatible with Part Numbers 15136039, 15164520, 19259313 by Brockington Zuniga

This switch FINALLY solved my intermittent "Service 4WD" error. This is a common problem on many GMC trucks (I have a 2003 Sierra). The most interesting thing about this problem for me is that before buying this replacement switch I took out the ORIGINAL switch and fully tested it on an ohmmeter with a meter according to the manual and all the ohm readings were perfect in the spec. Every day (and usually several times a day) the service 4wd light would eventually (but constantly) come on and STAY ON until I turned the truck off and restarted it. Also sometimes did not switch between 4 and 2WD. I've also previously tried cleaning and testing all relevant chassis bases (also a common cause of this issue) and they were all perfect. With the original switch and good testing, I still didn't want to (okay, lazy) switch to more complex resolutions. This means there are obviously a few other expensive, hard to service 4WD electronic/mechanical components that could be at the root of my problem, but I figured that even though my original derailleur was tested perfectly, I could get it for VERY little money Might as well try replacing that switch as it's the cheapest/easiest (reads like lazy long shots) possible solution. And it worked! For the first time in a year, everything was fine for several days and several hundred kilometers. I am 100% sure that this was the cause of my problem. Finally, it might not be the most expensive version of this Revain switch, but it worked great. So I'm glad I didn't spend the extra money on a more expensive (and probably identical) so-called 'new and improved' version of this switch at 2-4 times the price. Also, after taking apart and inspecting an old switch, it's not hard to see why moisture and normal use can cause intermittent failures. Mine had almost varnish-like stains on some of the internal contacts, and out of curiosity I tried cleaning them with iso-alcohol. It didn't seem to clear them at all.