My tailgate window goes up and down very very slowly, with most of the time I have to help it go ... not sure if it's the regulatir or the motor any help as far as which one it is and or help to get the job done in example utube, websites of that nature would be appreciated thx
CK5
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Tail gate window...
- Thread starter 79jenny
- Start date
Over time, I replaced all the tailgate parts. I replaced the gearbox and the window would not move, put the old one back and it worked. (wtf?) I ran 10g wire to front and wired in a relay thinking maybe that would eliminate a wonky switch. 10g to the tailgate (orange wire) switch also. Dedicated ground wire to the frame and refreshed contact points.. it's still a bit slow, but it's better than it ever was.
There someone turning out a "more power" rear glass setup, I think someone on here actually had experience with it. I don't recall anything beyond that, although I think the post also listed the website.
Although I'm sure more power isn't necessarily the best solution, it would certainly be nice to know that you had a motor that was up to the task, so that any time the stars weren't aligned with all the components, seals, etc., It would still go up.
Although I'm sure more power isn't necessarily the best solution, it would certainly be nice to know that you had a motor that was up to the task, so that any time the stars weren't aligned with all the components, seals, etc., It would still go up.
Well have come to the conclusion that it's a alternator issue it's on its last leg... and so not giving enough juice to get the job done...low on amps.. thinking of going GM CS130.. for more amps.. anyone know if it will fit on a stock 350?
nitro_rat
1/2 ton status
A set of relays in the tailgate to help get full power to the motor will help also. All of the current flows through the switch and its burnt up connections. Look at the back of your switch and you'll see what I'm talking about...
nitro_rat
1/2 ton status
US Body Source may make a fiberglass shell, I don't remember. Not sure if there's a steel one available.
i did the relay setup and added a switch in the rear under the tailgate, even with new felt it worked a thousand times better.
Jack Schmitt
Registered Member
I'm working on this same issue. None of the electric windows in my 85 k5 were barely moving and the rear not at all. With lube and some grounding repairs I got the fronts working decent. My cable was bad in the rear so I'm waiting on new cable to be delivered. My motor also seemed unresponsive but I'm going to investigate that further since I found poor grounds have been a problem in the other windows as well as the door lock actuators. While looking at the wiring diagram, I noticed that there is some sort of "protection" cut off related to the door pins. The wires run through the switch on the dash, then through the keyed switch on the tailgate, and also through the door pins to be sure the tailgate is closed. So all of those could be points of failure if your window motor seems unresponsive.
I redid mine last summer. New felts seals and rollers. Worked great before installed seals. Added the seals and really bogged it down. I lubed everything but still slow. Spray teflon seems to help. Leaves a messy white residue but helps.
New felt seems to be the reason people start having a problem raising the window.
When it happened to me, the only thing that helped was getting a thick cable to the back and running a relay which got me more power to the motor.
Good info here. I didn't realize how complicated these tailgates can be until you rebuild one. I wish they made a more powerful after market motor for these. I think the relay should help too if your voltage is falling due to old/weathered connections. Since nobody makes aftermarket tailgates for the Blazer and used market has dried up, has anyone had luck with a fiberglass one with glass and motor installed? I would think there would be strength issues holding all that in place.
Not sure if you took care of the alternator already.
Yes, you can get a CS130 for V belts. They put out more a lower rpm than he SI series alternators. I don’t remember what the factory application was. I have gotten two of them from Western Alternator with Iceberg case housings.
@500$k5
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Mine had the 37 amp alternator and once I had a gauge 2 cable to the back with the relays to operate the gate it was as fast as you'd expect.
I later upgraded to the 66amp 12si from the 10si 37amp.
Just to keep up with the aftermarket stereo
JDJ2810
Registered Member
Are there downsides to running the CS130 140-160 amp alternator's? I am getting ready to order the parts for my tail gate along with door window hot wire relay kits as well as the relay kit for the rear window.
There's no downside to a bigger alternator.
I was just stating that the bottleneck is the wiring
JDJ2810
Registered Member
Awesome. I hate wiring in general. With old Trucks it always seems to be the issue LOL.
I see all the pain I have endured on this thread. These issues pushed me to come up with a product to help in these restorations. I sell a relay kit that includes all the wire a fuse panel and instructions. Options are front only, rear only, full k5 kit, crew cab kit, and full suburban kit. My experience with these kits is no matter how much cleaning and grease you use to try to get the window to operate it will still have significant voltage drop. With the engine off the rear window should roll up and down no problem. The factory wiring will not allow a full 12v to the window due to the wire size. These issues have been solved. K5 Squared is the business name we sell through PayPal, and advertise on Facebook. I am happy to help any of you with a solution to this problem.
The fiberglass tailgate question I am working with US Body source to have this worked out. There are some other pieces we are going to get going as well. I have 2 of the full convertable tubs right now. One of the things we are doing is using the floor from 79 and newer in the 73-75 tub as an option. This will allow for more legroom in these trucks. Also on the tubs we have a fuel door option.
The fiberglass tailgate question I am working with US Body source to have this worked out. There are some other pieces we are going to get going as well. I have 2 of the full convertable tubs right now. One of the things we are doing is using the floor from 79 and newer in the 73-75 tub as an option. This will allow for more legroom in these trucks. Also on the tubs we have a fuel door option.
I'm having another issue right now. Seems more about alignment of the rear window. I can't get the SOB to roll up completely even with me helping it up. I took a totally empty shell, got the dents removed and inserted good components including a new motor. I have not tried a relay kit yet but I feel something is binding with the window and tailgate itself. Its frustrating spending all my damn time on this one tailgate when I have so much other stuff that needs to be completed. Everything is lubricated. I have not tried to lubricate the channels on the sides yet but I feel its more of an alignment issue at this time. The previous tailgate and hardware rolled up with no issues. Same wiring.
A
If it is not it will bind.
It took a few hours to lign up our 73 tailgate.
But once it was aligned and added the the relays and cable it was smooth sailing.
Alignment is the first thing.
If it is not it will bind.
It took a few hours to lign up our 73 tailgate.
But once it was aligned and added the the relays and cable it was smooth sailing.
The side channel should have felts in them. You might have the bottom glass channel backwards. It should line up with the glass, and has tabs that will run in the channel. The window I posted in the video above would not roll up all the way either until I added the relays. Even running the engine at 2500rpms wouldn't do it. The motor and regulator are back to original in that tailgate.
