AT4 Tech Package Tow Mirrors

kenac · September 14, 2021

So I'm a big dummy and bought a set of tech package (cameras, lane change, etc) tow mirrors on eBay for my '20 AT4 half ton.

Except they came off of a '20 High Country - a Chevrolet, and I didn't do my research before purchasing them.

I didn't notice until I went to install them and after the drivers side was on I realized there was a not insignificant gap on the bottom side where the bodyline and the plastic of the mirror don't line up. The good news is the camera and lights worked so I know the mirrors are good.

So I'm deciding what to do - try and find another pair from a GMC to purchase or try and rig these up to work somehow. It appears that the door design of the Chevy may be thicker because it has a longer/deeper bracket that goes through the door - hence why it didn't pair up correctly on the outside. Maybe that mount portion can be swapped out, I need to investigate.

Just posting on the off chance anyone has made the same bonehead mistake I did or knows anything about the difference between GMC and Chevy mirrors. It may be more hassle than it's worth and I'll put them back on eBay.

Chris Callanan · September 15, 2021

I can't help there, but does that mean you are getting rid of tech package regular mirrors (with Cameras, blind spot, etc)?

Been trying to figure out how to add cameras to the mirrors... Only way I've found so far is Intellihaul..

Transient · September 15, 2021

Tech package towing mirrors for a Chevy that you can't use. I know somebody that may be interested in them. They have non-tech tow mirrors and want to upgrade.

gemarsh · September 15, 2021

Have you checked to see if there are different part numbers?

I'm not quite understanding your problem.

I am thinking maybe there might be a support plate that goes inside the door for the heavier mirrors? Strange chevy doors would be thicker, that you would notice a problem mounting a mirror.

Just spitballin here.

kenac · September 16, 2021

On 9/14/2021 at 7:02 PM, Chris Callanan said:

I can't help there, but does that mean you are getting rid of tech package regular mirrors (with Cameras, blind spot, etc)?

Been trying to figure out how to add cameras to the mirrors... Only way I've found so far is Intellihaul..

Eventually, once I find some to replace mine. But I didn't install these with the gap on the bottom.

kenac · September 16, 2021

13 hours ago, Transient said:

Tech package towing mirrors for a Chevy that you can't use. I know somebody that may be interested in them. They have non-tech tow mirrors and want to upgrade.

I can't vouch for if/how that's possible but yea these are most likely getting resold.

kenac · September 16, 2021

13 hours ago, gemarsh said:

Have you checked to see if there are different part numbers?

I'm not quite understanding your problem.

I am thinking maybe there might be a support plate that goes inside the door for the heavier mirrors? Strange chevy doors would be thicker, that you would notice a problem mounting a mirror.

Just spitballin here.

The part numbers don't make any sense to me. It's an assembly so all the different pieces have different part numbers. Every identifiable part number I can find on the mirrors is either for a small part (dust boot, for example) or returns nothing online.

Visibly there is no difference from what I can tell but I don't have a set of GMC tow mirrors to lay side by side with these and measure. All I know is the bracket from my regular mirror doesn't stick out as far as the bracket on the Chevy tow mirrors does. Otherwise the dimensions are the same - it fits and all 4 bolts tighten down it just has a gap on the outside.

I may try it again and take pictures this weekend. Was hoping to find someone who had made the swap or made the same mistake as me that might be able to shed a little light.

GETGONE · September 16, 2021

GMC and Chevy doors are different. The body lines are different where the mirrors mount. There's another thread on here of someone replacing regular mirrors and thought the GMC and Chevy's were the same and they didn't fit and had a gap like you are describing when they put a Chevy mirror on their GMC.