What did you do to your NNBS GMT900 Tahoe/Yukon Today?

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89Suburban

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Mine are rotted, too. I'm not happy to pay $140 to replace them. The gap seems unnecessarily large for the hood hinge to pass through. I wonder if someone could 3D print replacements with a smaller opening. I may check into that.
@Fast_AT4 this something you may be capable of doing?
 

89Suburban

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Mine are rotted, too. I'm not happy to pay $140 to replace them. The gap seems unnecessarily large for the hood hinge to pass through. I wonder if someone could 3D print replacements with a smaller opening. I may check into that.

They really need to be flexible to get them in and out. Not sure if they make a material like that that can be 3D printed?
 

89Suburban

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it's not going to be as easy as it looks, to be effective it needs to be glued on from the bottom and have a lip edge to make it flush with the top surface.
What if it is printed as one piece? Without the flappy part?
 

Geotrash

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I've spent some time recently trying to figure out what voltage to run a agm battery at and man it's a mess.

I think you guys have the best chance of running them correctly with adjustment being able to be made to the battery settings with hpt. I don't remember his exact screen name but z71 something, I think was on to the settings.

I'm using one in the c6. it has no ecm voltage adjustments, I've switched to a newer pwm alt but I only have one sitting for voltage control and constant voltage just ain't right. a afm needs to be charged 2 or 3 steps to be fully charged and last a long time. what the voltage is at the steps is based on internal battery Temps. either by sensor or gm doing a bunch of crazy math's.

my volt runs a agm factory, but hpt doesn't define the voltage charge settings. so that's annoying, the yukon, hpt doesn't define the voltage settings to be adjusted on it, it came with a standard lead/acid, but I've changed to agm. I'm sure it needs a different charge settings, even thou it's not a cranking battery, so it probably won't give me the issue yours has. but still I know it's shortening it's life.



blah. I'm half temped to buy or build lithium batteries for everything I own except the volt. the last battery lasted 8 years in it, and it's now in the corvette as a temp battery because the Optima I bought it with finally gave up.
Yeah, I thought for a while that I had the AGM charging problem solved with a new alternator, but it's super clear to me now that AGM is not the right choice for these rigs because the software governs the battery management, and it was written for flooded lead-acid batteries. Putting an AGM battery in one of these is throwing good money away. I have been through three AGM batteries in the last 5 years on these rigs. The first two died within months so I chalked it up to defective batteries.
 

Doubeleive

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Yeah, I thought for a while that I had the AGM charging problem solved with a new alternator, but it's super clear to me now that AGM is not the right choice for these rigs because the software governs the battery management, and it was written for flooded lead-acid batteries. Putting an AGM battery in one of these is throwing good money away. I have been through three AGM batteries in the last 5 years on these rigs. The first two died within months so I chalked it up to defective batteries.
I have 4 year old agm's (interstate) in the yukon and the silverado and both are fine so far...
4 years around here is about max life so I have been watching for signs of them getting weak but no signs of that yet
 

mikez71

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I've spent some time recently trying to figure out what voltage to run a agm battery at and man it's a mess.
I've been looking into the same. So far I've tuned the charging to not drop below 13.5V, but am thinking about unplugging the current sensor. I am guessing that without the current sensor, it might be less skimpy with the charging. From what I can tell, undercharging seems to be the main issue.

Yesterday I had 12.5V after sitting a day, whereas before I was reading 12.3V. Not sure if it's my charging settings or because I put a battery tender on it once for a couple minutes.. (months ago)
 
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Doubeleive

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I even had the silverado running the radio and 2 amp's for over an hour last week on the battery while I helped a friend at his storage unit, no low battery alert or anything. I wasn't blasting it but it was on enough for us to listen at a normal volume.
 

j91z28d1

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does black bear have settings for agm swap? they might be the best to do that having access to many different vehicles codes. one of them showing how gm handled agm would probably go a long way.

I still like that agm doesn't leave the trays and stuff eat up over time. that's worth the money in something like my c6
 

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