'98 Heater blend door groan/squeek cycling hot cold hot cold

[LIKE2WHEEL]

Perhaps I can be of some help here; it seems many have had this problem, but nobody took the time to post their results.
Wife complained about the groaning/squeeking heater for some time. Dead battery caused my blend door to cycle constantly between hot & cold. This is what the computer is supposed to do (once) to learn where full hot & full cold is. Computer showed codes B0408, B0415, & B0416. Mitchell repair info has you checking all the circuits, then replacing the actuator with a "known good unit"($). If that isn't the solution, then replace the heater control module($!).
I decided to take out the actuator to take a look at it. Turns out it's not that hard to get out. The bolt in the back is not a bolt, only a pin. Thank God. The 2 front bolts are accessible with a 5.5 mm box end ign wrench after getting the vacuum pod out of the way. It takes some tedius wrenching, but it's better than removing the dash as others have suggested here. After getting it out, I took it apart to see if I had the famous "split gear problem". Sure enough the big gear was split & rubbing on the case, this was causing the groan/squeek problems. I checked the door movement & it was free & quiet. After replacing the actuator both problems were solved. So if your blend door is groaning, be prepared to change your actuator soon, because if you loose battery power, your computer will not be able to calibrate the door. Also the aftermarket actuators seem to be incorrect if you have climate control.
I tried to post this in the How-To thread, but I was not authorized. I've gotten some good information from this fourm & hope this helps someone else.

[Cloud Strife]

Which brand of replacement did you get then?

[LIKE2WHEEL]

Originally Posted by Cloud Strife

Which brand of replacement did you get then?

GM - aftermarket looks right, but didnt work. Fewer pins in the electrical connection.

[circuitprotector]

Thanks like2wheel! you just saved me 700 bucks (not like i was going to pay that much anyways) the stealership told me that they would have to remove the dash to get at the actuator. after reading your post i decided to do it myself. everything worked out great. i even used a small wrench that i got for free at a garage sale...lol
The dealer want 224 bucks for the part so i got it from gmpartsdirect for 174.
Thanks again!