96 blazer transfer case problem

we just bought a 96 blazer.
In 2hi the front wheel indicator lights up. Shouldn't this be out in 2hi?
Also when driving in 2hi, the light for the front wheels will go out around 60 or 70mph. When you slow down it sounds like the front wheels are trying to engage. After you stop on shift into 4hi or 4lo and then back to 2hi, the sound stops. Then maybe 30 or 40 miles down the road it will make the sound like it is trying to engage.
help?

we just bought a 96 blazer.
In 2hi the front wheel indicator lights up. Shouldn't this be out in 2hi?
Also when driving in 2hi, the light for the front wheels will go out around 60 or 70mph. When you slow down it sounds like the front wheels are trying to engage. After you stop on shift into 4hi or 4lo and then back to 2hi, the sound stops. Then maybe 30 or 40 miles down the road it will make the sound like it is trying to engage.
help?

Check your vac actuator under the battery for holes or tears, check the vac line running from the vac actuator to the transfer case vac switch..If those are ok, it's the vac switch on the transfer more than likely...But I would lean more torwards the actuator not engaging the front fully because of vacume leak.

Check your vac actuator under the battery for holes or tears, check the vac line running from the vac actuator to the transfer case vac switch..If those are ok, it's the vac switch on the transfer more than likely...But I would lean more torwards the actuator not engaging the front fully because of vacume leak.

I checked the actuator, that looks fine (how do they expect work on these vehicles, there is no room) the 4wd engages fine and everything, it is like it doesn't disengage when I shift to 2hi. So I will replace the vacuum switch and see what happens.

Thanks