hi all Well i have a 1978 blazer 4x4 and the 4wd stopped working i go to put into 4 lo its a no go so then i try 4hi agen and it just blinks then goes back into 2hi ???????????????????

 

What year is the truck my guess its not a 78 if its blinking and going back to 2wd?

 

Yep. Clarification is necessary.

 

my bad 1987 S10 Blazer Any one have an idea on what I could check as to why my 4wd quit working When i first put it into 4 high it turned on and the light came on to signify that it was on. Then it started kicking in and out (the light was going on and off at the same time) and then it quit all together. I have a Is there some kind of actuator or something in either the front differential or in the transfer case itself that could have gone out?

 

umm i think theres a vacuum line on the s10 blazers right? lol i dont know cause i've only had fullsized ones that have like a worm drive that locks it in to four. But i think theres a vacuum on the s10s haah i have no clue what i'm talkin about. Have you changed the t-case fluid? or checked all the linkages?

 

I would check all of your vacuum lines and try to isolate if the Xfer case is ingaging which i am sure it is. if the front shaft is spinning the case is working. then you can isolate it to the front axle which is prob the hubs on the vac actuator or a vac line. it will take a little investagating. good luck!