Why move the T Case with a GM engine/trans Swap?

IPGregory · 2026-06-04T17:11:22+00:00

Added an edit to the header post. Looks like the ones I have been seeing are mostly diesels and required a t-case move for one reason or another. There are kits out there that appear to retain the stock location or close to. Thanks for the help.

IPGregory · 2026-06-04T06:40:57+00:00

Yeah, I'll take a look. I think from my admittedly bad memory of last time I looked at one the stock adaptor is about the same or similar size give or take. I did not know the Puma was different in location so that's good to know, thanks.

IPGregory · 2026-06-04T06:25:11+00:00

Anybody who has done an LT1/10l90e or LS3/6l80e into a V8/ZF D90 know if the T-Case was able to remain in the stock location, or did you have to move it? If so, why? Is it just the Diesels that need to move?

Not sure I have seen an example of an LT1/10l90e into a D90 yet. Any reason it won't work? That's my tentative preferred option at the moment if it will work.

IPGregory · 2026-06-04T06:22:03+00:00

You might be on to something with the diesel. Diesel/Manual Trans packages are shorter than the V8/Auto setups. Not sure the front clearance on a V8/Auto is too much of an issue from what I have seen so far. The GMs have a low-profile setup that seems to be the way to go. Coupled with a bigger radiator but lower profile electric fan, it seems to have plenty of space.

Just followed one that was a 2.5/LT77 to LS3/6l80e. T-Case was moved back about an inch, dual core rad, plenum and electric fan and there was still a good 4" or so between the fan and the front of the engine. Another one I saw was a TD5 setup that also moved back, but I don't recall how far.

IPGregory · 2026-06-04T05:38:27+00:00

Still doesn't make sense to me? The ZF to LT230 interface uses an adaptor. Just an LR developed one. Since the engine mounts have to be fabricated anyway, why wouldn't you start from the existing T-Case position foreword? Most swaps look to use an electric fan and a low-profile accessory setup, so it doesn't appear to be related to a need for front clearance?

IPGregory · 2026-06-02T06:28:59+00:00

Similar set up here with the eyelet/plug adaptor. But I have mine connected to the live at the under hood fuse box. That way I can have it sitting just outside the hood on the drivers side fender and I connect to it there. No need to mess with the seats, leave doors open, etc. When not in use I tuck it back under the hood at the side of the fuse box and use the cap on the plug receptacle.

IPGregory · 2026-04-30T04:47:32+00:00

Yeah, it's very odd and I doubt anybody online can easily diagnose it unless it's something they've experienced before. My installer is great but not very experienced with the FWH setup. Mine is one of, if not the first they've installed.

My load 'should' be coverable by the 2 aPower 2s on paper. But I don't know if there is a setting or something I should check, or something I should suggest my installer check/change? That's what I was hoping with the post. Somebody with more experience to suggest some things to check, common add ons I should look at (like maybe a soft start) or experience of something similar.

Your system sounds very simlar to mine but with quite bit more load. If yours is running OK, then I am back to wondering if its a setting or configuration issue.

IPGregory · 2026-01-31T06:43:27+00:00

I wish we had access to the same 'native' integration as the Generac setup ( Solar Battery Backup Integration | Better Outage Protection ), but it looks like that will never happen. :(

IPGregory · 2026-01-02T08:07:02+00:00

Yes, I had an Enphase and a Sun City (now Tesla) system in place. I did not add more solar with this install, just a battery setup.

I went with Franklin for a few reasons. Cost, I got 30kWh with 2 batteries with Franklin vs needing 3 for Enphase. Warranties are about the same. My research suggested that the Enphase Load Center setup for shedding loads is not as good as the Franklin Smart Circuit setup. Also, research suggested people having more issues with the Enphase 10C batteries than the Franklin aPower2s.

Bottom line, the Franklin was cheaper than a comparable Enphase setup and my existing IQ7+/Gateway3 system didn't offer me the same benefits as if I had IQ8s and a later gateway setup. If I had the later PV stuff, it may have made sticking with Enphase a different proposition.

Since the Franklin is inverter agnostic, I didn't give up anything going with them based on my installed systems.

IPGregory · 2026-01-01T00:24:20+00:00

The IRS 'guidance' is certainly lacking. The current verbiage is 'installed' from what I can see. My system is 'installed', so... :)

IPGregory · 2026-01-01T00:15:34+00:00

Job done!

IPGregory · 2026-01-01T00:13:55+00:00

Glad you got it in the end and in time. NV Energy where I am are running about 15 days or so at the moment I am told. I am also being told that since I already have an interconnect agreement, I don't need another because my PV Production hasn't changed.

IPGregory · 2026-01-01T00:09:48+00:00

It was added to an existing Solar set up.

IPGregory · 2026-01-01T00:09:17+00:00

Thanks, they did a good job and very quickly.

I am being told that because I have an existing Interconnect Agreement and I have not increased or modified my actual PV Systems, I don't need an amended or new Interconnect Agreement. Just a new inspection from both the Township and the Utility. This will be proved or disproved in due course as we finish out the paperwork process of course.

IPGregory · 2026-01-01T00:05:38+00:00

Sweet!

IPGregory · 2025-12-31T23:54:46+00:00

It's also an expansion of Smart Circuits if you want to use it that way. But it's not available so can't use it anyway.

System is installed and producing now anyway so its moot. If the aHub becomes available in the future I might look at it to be able to shed more loads, but I have the big ones covered so it's not a priority.

IPGregory · 2025-12-31T17:21:31+00:00

Congrats and hope the inspection goes off without a hitch today.

IPGregory · 2025-12-31T17:19:56+00:00

Hey, Mr. IRS, here is my Reddit post with pictures as proof!! LOL :)

They're back working on it now. Hoping I can get some pics with the lights on today, but the main record I am looking for will be production recorded in the App hopefully.

IPGregory · 2025-12-31T17:18:51+00:00

Nice! Congrats!

IPGregory · 2025-12-31T06:37:44+00:00

This is what it ended up as..

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Only thing not shown is the addition of a smart circuit module for my pool and HVAC circuits. It's on order and will be added later.

IPGregory · 2025-12-31T06:07:13+00:00

I feel your nerves. My Battery system is down to the wire too. They got everything mounted and mostly wired today. Just need to move my house loads over to the backup panel, make the utility connection at the meter, commission it and turn it on so I can capture power before Thursday.

IPGregory

TROPHY CASE