6.5 Swap

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Slooptin

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Joined
Mar 6, 2017
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Location
Houston
First Name
Vance
Truck Year
1985
Truck Model
k30
Engine Size
454
So, I currently have an 85 k30 (454/400) and I've been toying around with the possibility of a swap, mostly for mileage (i.e. possibly diesel, but definitely overdrive). I have a line on a 92 k2500 with a 6.5 and I'm assuming 4l80e (not specified, but its not a 5 speed). I feel like I'm pretty mechanically apt for this job, but wondering what all is involved in pulling the old engine/trans and replacing with this one.

I'd be keeping the np205 from my truck, so I know I'll need the adaptor/mount for the 205/4l80 combo and I'm assuming motor mounts unless the big block ones work on a 6.5. I'm curious about wiring for the 4l80e since the 6.5 is mechanical, I'm wondering if I can make the 4l80e controller from the gmt400 truck work or if I'll need to buy a new standalone?
Can I can keep the existing fuel tanks and tank selector valve or if I'll need new ones?
I'm also wondering about AC and exhaust routing. Could I use the compressor from the gmt400 truck?
Is there a way to relocate the turbo to the driver's side since it looks like it might interfere with the stock AC box in my k30? I'd really prefer to keep AC since it currently works and I'm in Texas, plus the 205 is a passenger side drop and i believe gmt400's were driver drops so there isn't much room for a 3"+ down pipe on the passenger side

I'm not looking to make a ton of power with the 6.5 and I'm aware of their shortcomings, but I can probably break even on selling my current engine/trans and the rest of the gmt400 truck so it seems viable to me right now, just looking for some additional input
 
Last edited:

Rickf

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Jul 29, 2017
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Location
Grafton NH
First Name
Rick
Truck Year
1974, 1954 & a 1937
Truck Model
K20
Engine Size
350
I believe 6.5TD vans and Hummers have a center mount turbo. A body lift kit is needed to use a passenger mount turbo in a squarebody for the down pipe to clear the heater box and firewall/floorpan area.
 

Rickf

Full Access Member
Joined
Jul 29, 2017
Posts
463
Reaction score
546
Location
Grafton NH
First Name
Rick
Truck Year
1974, 1954 & a 1937
Truck Model
K20
Engine Size
350
The 4l80e should have a factory stand alone controller, maybe behind the glovebox. I have a '93 w/a mechanical injected 6.5td and a 4l80e, I'd check but it's covered with snow.
 

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