I have searched and tried all of the things that I'm able to try, without possible internet connection, both here and all of the info on the Arch wiki.

The wireless will occassionally work and then not. Right now, it's not able to connect.

If anyone is willing to walk through any other troubleshooting steps, keeping in mind the lack of internet (no eth on the laptop), that would be awesome.

--Manjaro XFCE 17.1.16 stable
--Triple boot with MacOS and CentOS.
--rEFInd as boot manager (grub bootloader)

--Just put in a new SSD and thought that may be causing issues, but wifi is flawless in other OS's.

it seems you're not the only one - try these results.

I would recommend the following makers of network adapters for use with a Linux box because they work so well:

Atheros, particularly with chipset numbers AR9271, AR9170, or AR7010
Ralink
RealTek

Several WiFi adapter makers have each created several models of USB devices, as well as mini PCI half cards for laptops
using their chipsets as controller chips inside. Most are functional in Linux.

Here is a good place to look for which devices use which chipsets: https://wikidevi.com/wiki/Wireless_a.../Chipset_table

I would STRONGLY avoid using ANY Broadcom network adapter on a Linux box. Why? Because their drivers are closed-source
and most of their WiFi adapters/drivers do not work RELIABLY in Linux.

This is very likely why Broadcom is trying so hard to buy Qualcomm (makers of Atheros devices) that they recently
offered $115 BILLION to buy the company. Even President Trump is trying hard to block that sale. His advisors likely
know what a disaster that would cause for opensource networking if Broadcom buys them out. They surely would
close public specs for any future Qualcomm-type adapters. Besides, Qualcomm have the best patent library
for network devices. (ie: CDMA)

Sorry to necropost, but I had a similar problem and found a workaround which maybe others will find useful.

I installed Manjaro on a 2008 MacBook last month, and saw that wifi was very flaky. It would connect for a short while, then disconnect, then reconnect, and so on.

I noticed that it was connecting fine on the 2.4 MHz band but failing on the 5 MHz band. It appeared that it was randomly switching between bands, instead of choosing one and sticking to it. My router allows me the option to give each frequency a different SSID and password, essentially creating two separate wifi networks. I created a new network SSID on the 2.4 MHz band, gave it a new password, and my MacBook connected to it securely.

It was only later that I discovered it was possible to choose a particular band in the Network Preferences for the MacBook...