just bought 97 blazer v6 4x4...and already a problem...i have found a thread on here that what these ppl r discribing is exaclty wats goin on with min .. you get it up to bout 60 the slow down to 30 and this wailing griding noise occurs then you hit 4hi and it stops....iv got vac switch im replacin tom and vac acuator and the cable too...ne other possibilities this might be...will post the link i found https://blazerforum.com/forum/2nd-ge...x4-2272/page2/

 

I had a similar problem and when I replaced the vacuum switch, the problem was fixed. Make sure ATF hasn't been sucked into the actuator and such. That is a occurrence that seems to be on the extreme end of this problem, but better safe than sorry

 

best i can tell it hasnt.... will probably go ahead and replace the diaphragm acuator any ways just to be on safe side .... thanks for the response

 

If the switch hasn't seemed to fix the problem, it maybe the actuator still, make sure the cable moves freely. It needs to be able to move about a half in to 3/4 inch. It could be binding, or there could be something not working or messed up inside the axle.

 

switch was stuck close but there was 2 problems the diaphragm had a hole on the bottom side replaced diaphragm and vac switch problem solved thanks for all the help much much appreciated!!

 

ok nevermind on 4wheel drive workin it felt like it was engaged but went ahead and jacked up front end and in 4hi the front passenger tire spins freely....just gettin a little movement out of cable now before was goin in half inch to 3/4....

 

Well if it was pulling and its not now, it could be a vacuum leak somewhere, the cable could be binding, or there is a problem with the shift fork, etc inside the passenger side axle tube.

To check to see if you have four wheel drive, pull the cable about 3/4 of an inch and then lock it off with vice grips to see if you have 4WD. If you do have 4WD then it is vacuum/actuator related, if you don't then my guess is it is something inside the actual

 

hmmm... i replaced the cable too when i done the switch and diaphragm... before i changed cable the cable i could pull it in 3/4 " you think i could of knocked something off track inside on shift fork?

 

i took cable completely off and pulled where the cable connects to shift fork and im only gettin about 1/4 of play with out cable..i can feel it clickin like the coupling is connecting with the teeth of axle...it may have ground the teeth off....no tellin how long it has been like that before i got it

 

anyone kno what you do to remove sfift fork....remove hub etc...