I have a 2000 Chevy Blazer LS. When I click out of 4wd into 2wd there is a clunking or a thud noise that comes from underneath. I also have a vibration in 2wd after I have used 4wd. Any suggestions or any other previous topics would be greatly appreciated.

 

Sounds like a bad U-joint. Have a trusting friend watch for a jumping or clunking one while you slowly alternate between reverse & drive with your foot on the brake.

 

Sounds like your front axle isn't disengaging properly. How many buttons do you have on the 4wd switch? 3-button == NV233 and 4-button = NZ236.

Why don't you bring it over to my house and we'll get it fixed up before this storm hits! LMAO!

 

I'm en route.....lol..... I have the three button switch

 

I really wasn't joking. I have time. It isn't snowing yet.

A clunking noise sounds more like a problem with the front driveshaft than the front axle engagement. Most of the time, a partially engaged collar in the front axle is described as a clicking noise as the teeth on the passenger side extension axle skip over the teeth in the collar.

 

I got a feeling its the u joint in the front but I'm not 100% on that.....I also have to replace the differential cover.... so i have a little bit of a project on my hands

 

I have the differential on order and should be here by Tuesday, but I had to order two different sizes and find out which one it is when I take the old one off.

 

What are you referring to when you say differential? Can you give us a part # so I can look it up?

 

Differential cover for the rear.... there is two sizes listed for a 2000 LS

 

If you don't have a ZR2 it is the smaller one.