Thrunite T2 GT-FC40 swap question

Hello! First post here, been lurking a while. I’ve read about a few successful swaps of a GT FC40 into a Thrunite T2. I have a Convoy S11 that I’m willing to pull the GT-FC40 from and drop it into my T2. I’ve never done an emitter swap before, but I’m no stranger to working with electronics & soldering.

I haven’t seen an instance of this particular swap where someone has just swapped the entire MCPCB. They all appear to have reflowed the emitter. The Convoy S11 MCPCB is ever so slightly smaller than the T2’s stock MCPCB, but the screw holes appear to line up well enough to work. Is there an advantage to reflowing? Can the entire MCPCB just be swapped without causing harm?


I swapped a 4000k GT-FC40 into my blue T2. It was already soldered onto a mcpcb and I had no issues what so ever. The stock centering gasket worked as well.

Awesome, thanks for the quick response!

I 2nd what’s been said. I’ve done the swap. I forget if the bezel was glued. A heat gun and rubber gloves will help if it is.

Make sure your new solder blobs are low and will not contact the underside of the reflector.

This is a good option for a first-time emitter swap since there’s lots of room. Have fun!

Back with a little update. I successfully swapped a 5000k-5500k GT FC40 into my T2! Since then, this has become my favorite light by far. Nice even, neutral tint compared to the original emitter. Couple of quirks now:

1. This emitter seems to gets much hotter than the XHP70.2. I don’t have any tools to measure accurately, but it’s noticeably hotter. Totally fine in low & medium (where I use it most) but it gets hot in high, and uncomfortably hot in turbo.

2. I can’t measure it, but it’s definitely not as bright as before. It’s a welcome trade-off for the much improved tint, so it doesn’t bug me. It’s still extremely bright!

3. The moonlight mode is now much dimmer than before. I consider this a big positive! Again, I have no way to measure this, but you can comfortably look directly at it when it’s on. It’s awesome for very dark situations, middle of the night, etc.

4. I had an issue with the original Thrunite battery. When engaging turbo mode, it would increase brightness for a split second, then go back to what looked like high. I put a different battery in, and now it works flawlessly. Guessing it needs a battery capable of delivering more amps? The old battery didn’t specify. The battery that’s in it now is a NitecoreNL2150HPi, spec’d at 15A. Maybe I have a bad battery from Thrunite? Not sure on this one.

Other than that, fun project, and a great outcome! Here are some pics.

Nice work! You are definitely not alone with the “turbo flash” problem. I have all 4 colors of these and they all display this behavior. I haven’t bothered with getting new batteries because I don’t use turbo all that often. Thanks for the update!

I have a brown/tan T2 which I swapped in a 4000K FC40. I used the 20mm mcpcb it came on. The holes and notches weren’t a perfect fit but it works and the Thrunite centering ring fits perfectly. I love it!

I must be lucky because my Thrunite cell has no issues when using turbo. Turbo does produce a lot of heat but that is the nature of this led. However, I seldom use turbo on any lights I have so I never really find the heat an issue.

The bezel is glued with red threadlocker. I used a pair of wood blocks to hold the head, then used a heat gun and twisted the bezel off wearing a leather work glove. (the piece of wood had a large hole drilled in it and then cut through the hole to make two halves that grip. You have to look closely to see the cut.)

I should have mentioned, I did wind up doing the full mcpcb swap, and it fits just like MtnDon described. I used it heavily over the summer and into the fall. Tossed it around quite a bit, in and out of bags, camping, etc. No issues at all. The mcpcb is definitely mounted solidly.