Suburban tailgate window help?

[83ChevyK5Blazer]

1991 suburban, just switched to a new tailgate shell and the window is not really wanting to go up or down.

When i switched shells i deleted the saftey switch from the pass side latch. It has been tested and is not an issue

Voltage from the key switch is 12.5 in both up and down directions with engine off using the key switch.

The motor is new, and spins either direction grounded against the regulator but not engaged to the regulator.

Once hooked up it will slowly raise but will not lower the regulator, with the glass in it will raise with help but it isnt happy about it.

I've swapped in two regulators and both do the same thing, new motor works better than the two older motors i've tried but im at a loss as to what im missing.


Other question is does anyone know if the regulators for a k5 tailgate is the same as a burb, ive got a manual regulator in a k5 gate sitting in storage.

 

[rampage]

Grounding to the regulator is not the best way, especially of you have rust/corrosion where the hinges attach to the tail pan. Run a dedicated heavy gauge ground wire from the motor to the frame. You may be reading 12V right now but once you try to draw power the resistance from any corrosion will not let the amperage needed to drive the motor.

And IIRC the regulators for the ‘burb and Blazer are different. Look up the part #’s in the LMC catalog.

 

[83ChevyK5Blazer]

Added a 12ga wire(what i had on hand) from the motor mount bolt to a bumper mount bolt. No change in the motor lowering the window or raising it up.

 

[rampage]

Did you make sure it was to bare clean metal?
Then I’d look into the window felts being dirty or needing to be replaced. Also the rollers can have flat spots or the guide that they run in can be dirty or have dried up grease that’s dried out and hard.

 

[JOES89K5]

Hello I guess yours not too different then Blazer but mine broke in the coldest day this past year. Window came down but wouldn’t go up. The cable was the problem. But what I didn’t know before tying to remove it that there’s a loaded spring underside of unit. Well to make long story short after it almost took my finger off I removed the whole unit. Opened the box that cable goes called jackscrew cleaned it out installed new cable. I installed new key switch before putting everything back. I used a drill to move window up in place cause of loaded spring. Installed cable to motor. My stop switches worked. I also replaced the plastic wheels on the unit. Greased everything. The system works great.

 

[JOES89K5]

I don’t think the regulators are the same.

 

[USSkoval]

Added a 12ga wire(what i had on hand) from the motor mount bolt to a bumper mount bolt. No change in the motor lowering the window or raising it up.

Still check the voltage while trying to raise or lower the window. There could very well be a bad spot inside the wire that runs under the truck. Or a poor connection at the rubber connector.

Burb/K5 power regulators are different, but I don't recall about the manual regulators.

 

[Billyworld]

Grounding to the regulator is not the best way, especially of you have rust/corrosion where the hinges attach to the tail pan. Run a dedicated heavy gauge ground wire from the motor to the frame. You may be reading 12V right now but once you try to draw power the resistance from any corrosion will not let the amperage needed to drive the motor.

And IIRC the regulators for the ‘burb and Blazer are different. Look up the part #’s in the LMC catalog.

I agree. Iirc, grounding the regulator will cause problems.