i can put my blazer in 4wd hi or lo and the TC is engaging and the front driveshaft is spinning but the cv axles arent moving, it looks like the gear oil leaked out both sides of the diff, i was wondering if that the diff was too low on gear oil it would stop it from engaging when you turned on your 4wd. it was working perfectly the day before and then just wouldnt work this morning to pull my self out of my drive way. anyone know what it could be

 

low gear oil shouldn't cause the front dif not to engage. it's probably the actuator for it has an issue.

 

ok just wasnt sure because, it has some kind of sensor or some **** beside the vacuum line

 

low oil wouldn't give you a front diffy lock issue. Its either a bad vac line or a bad actuator .

Being low on oil would be an issue when its locked... IT can cause damage to the gears.