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Will Not Engage into 4 wheel Drive

tahoe33

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tahoe33 Enthusiast

tahoe33

Posted
Posted

I have a 1995 Tahoe with 75,000 miles and it would not engage into 4 wheel drive yesterday morning when I pulled into the muddy field. Later in the day it worked. Has any one had problems with the Thermal Actuator for the front axle. Does any one have a copy of gm service bulletin #76-43-01 dated april 1997. Has any one had this service done.

 

 

Thank for any reply

 

 

Bob

tahoe33 Enthusiast

tahoe33

Posted
  • Author
Posted
I replaced the acuator myself in about 30min on my 95' burban. It is a simple fix.  :banghead:

 

 

 

 

 

Did you replace it with the standard one or the new unit that requires a new wiring harness?

 

Did you purchase it from GM or an auto parts store?

 

Thank

 

Bob

Shawn T Enthusiast

Shawn T

Posted
Posted

I replaced two on my OBS, the first one was the OEM, it failed after one cold winter. Next I bought an aftermarket electric one. That was six years ago(88 Silverado) and my brother owns it now. The actuator still works. There are two advantages to the electric ones.

1. Instant Engagement of the front differtial

 

2. A lot more reliable.

 

I would recomend the electric motor driven unit. It is easy to install(instructions included for the one wire conection) and you will love it when you engage four wheel drive and it hooks up immediately.

Jeremy WI Enthusiast

Jeremy WI

Posted
Posted
I replaced two on my OBS, the first one was the OEM, it failed after one cold winter.  Next I bought an aftermarket electric one.  That was six years ago(88 Silverado) and my brother owns it now.  The actuator still works.  There are two advantages to the electric ones.

1. Instant Engagement of the front differtial

 

2. A lot more reliable.

 

I would recomend the electric motor driven unit.  It is easy to install(instructions included for the one wire conection) and you will love it when you engage four wheel drive and it hooks up immediately.

 

 

 

 

I agree the electric motor style is more reliable than the thermal actuator. In addition to what has been posted the electric motor style won't disengage when you turn the key off- the thermal actuator cooled down and released with no ignition power. Do a google search for actuator and 26060073 (26060073 should be the part number for the electric motor front axle actuator, you should also be able to find a post that will give you the correct part number of the wiring harness you need. You can order the parts online through a few of the sites sponsors- gmpartsdirect.com and partszoneonline.com to name a couple

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