I tried posting this under another thread but no one had responded so I made a new one. I have a 98 blazer 4wd with the 3 button switch on it and I can't shift into 4hi at all. My lights will blink on the switch then sometimes either go out all together or will keep the 4hi and 4lo lights on. and when I shift it into 4lo the truck feels how a car feels when the clutch is slipping and barely move (it is an automatic). is this just a problem with the vacuum line and I need to change it or what? any help would be great.

 

Is your service engine light on? If so, get the codes pulled. If not, I think the dealership can pull the error code from the 4wd encoder.

 

my check engine light is not on at all the only time it came on was when my coolant was low when I changed my radiator.

 

Now that I've thought about it some more, I think the sequence of blinks is actually a code that indicates what the problem is. You might need to go to the dealer to find out what the code means. Or try watching the sequence and search for some information on it?

 

hey man, i'd say check the fluid first! the most common problem is low fluid. some of the t cases need special GM fluid so look into that( if so it will say rite on the case)

 

I heard that somewhere but I wasn't sure if it was true. I will definitely look into that.

 

theree used to be, and proble still is a DIY thread on the electronic 4x4 system. Someone went into great detail about trouble shooting the problem.

I dont think it a vacuum line issue.