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99 Suburban 6.5 to 5.9 Cummins Swap

usanumber1

Well-Known Member
Messages
128
Reaction score
299
Location
San Diego
I have a 1999 K1500 Suburban 6.5L Diesel I picked up Oct 2016. Plans from the start were solid axle swap, which I completed, and to clean it up all around. While I was collecting parts for the SAS, I rebuilt the entire front suspension: bushings, tie rods, idler, pitman, etc. It drove just OK still. After the ORD SAS Dana 60 kit, it tracks straighter and drives smoother than it did as IFS. No contest. Back to the powertrain, the 6.5 was pissing me off because it was giving me no-starts. PMD was already moved. NBD. Bought new PMDs, they worked. A few thousand dollars and years later, I thought I had it all sorted out with a completely remapped and programmed ECU, reman IP, got rid of Passlock, and removed vacuum pump and wastegate, was running great until about May this year and then it gave me a no-start, had to leave it parked and come back the next day. That was the last straw.

A cummins swap was always on the list of things I'd love to do, but I was putting it off because it's expensive to do properly. I found a P Pump 12 valve in San Diego, they delivered it, and I got to work cleaning it up. I'l come back and edit with part numbers later.

full degrease with Purple Power and a hose,
new water temp sensor
new oil pressure sensor
new throttle position sensor
KDP fix
different upper and lower waternecks
different alternator bracket from Maibach Tractor
vacuum pump delete and GM hydroboost pump conversion from Quickdraw
driverside A/C compressor mount from Carrick Customs
new heater hoses
new fuel filter
new oil filter
lots of cummins beige paint.
new style exhaust manifold
new turbo drain line build with -10AN fittings and an AN adapter that goes into the block from Fleece performance

I just moved so project is on hold until the shop space I'm renting from a friend is organized enough to begin the swap. I'll try to keep the engine posts here, and the suspension over there.

A link to the SAS and some upgrades is here:

Truck as it sat a few days ago, I'm planning on a completely new bumper, so i already removed the old one and set it free because it was dented and effectively worthless. The factory crossmember is still in place, will be cutting and rebuilding when the engine is out.

Untitled by mariley85, on Flickr

Truck with mock up of ABS valence bumper, and one I crudely photoshopped with the Hella 9000s.

Untitled by mariley85, on Flickr
Untitled by mariley85, on Flickr

Engine the day it followed me home

Untitled by mariley85, on Flickr

Engine painted and being prepped at various stages

Untitled by mariley85, on Flickr
Untitled by mariley85, on Flickr
Untitled by mariley85, on Flickr
Untitled by mariley85, on Flickr
Untitled by mariley85, on Flickr
 
One of these days I’m going to round up everything that I need to install some on my truck. I like the look and especially how they seem to be a lot stronger and won’t break every couple of years like the originals do.
 
Other specs/parts will be
4L80E
early Duramax intercooler and radiator
external trannycooler with fan likely under truck.
the 220gph FASS fuel pump that came with the engine
SSOR motor mounts
Quick4 trans controller
Just remember the 4L80e will hold just so much torque and modifying the Cummins quickly sends the torque output way beyond what it can handle stock.
 
Just remember the 4L80e will hold just so much torque and modifying the Cummins quickly sends the torque output way beyond what it can handle stock.
Thanks for the concern, but I’m well aware. A built 80 is in the plans. I’d love an Allison, but the adapter, Trans, new t case, and controller, also modifying the tunnel make it a lot more work and money.
 
Interesting how they cater to the drag racing people talking HP when it's torque that kills them. Burb's are heavy mine tipped the scale at the land fill at 7.5k after dumping garbage etc. and that is with only two (2) light weight racing seats and no other seating.

A low stall converter combined with "lower 1st gear" from transmission center dot net in Louisiana and all the other enhancement goodies for the 4L80/85e would IMO be a far better setup for a Cummins to GM conversion as long as it's not drag raced.

However; I went with the 47RH built to much higher torque capacity specs. than any 4L80/85e could handle according to all the research I did one the web a few years ago so there maybe some newer mods that I don't know about for the 4L80/85e that will bring it up to holding more torque.
 
Engine parts list update with numbers when available.

Water temp sensor ACDelco 213-77
Oil pressure sensor OPS14
Throttle position sensor TH175
TPS bracket 3925380
Upper water neck 3285102
Lower water neck 3934877
Tensioner pulley bracket 3925196
Standard 12V tensioner pulley
Alternator bracket Maibach Tractor similar to 3287096
94-02 fan hub assembly
Vacuum pump delete for GM hydroboost pump conversion from Quickdraw
Driverside A/C compressor mount from Carrick Customs
Fuel filter BF1233
Oil filter BT7349
Exhaust manifold gaskets MS92089
Block heater cord 251919
Timing cover gasket set TCS46001
Mech fuel pump gasket 3939258
Low turbo exhaust manifold
Custom turbo drain line, -10AN fittings, block drain adapter, FPE-CTDA-10AN
Belt will be a 6 rib, likely 94". Didn't have time to stop by Napa before they closed last night.

Unfortunately I won't be using the awesome idler pulley bracket that Carrick built and sold along with the mount, so if anyone wants it, it's brand new with a fresh coat of Cummins beige paint and for sale. I'd love to use it, but relocating the tensioner from the side of the engine renders it useless.

Untitled by mariley85, on Flickr
Untitled by mariley85, on Flickr
Untitled by mariley85, on Flickr
 
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It’s a Cummins bracket and the original tensioner. Part numbers above. Also, i’m Probably going to change to a counter clockwise rotation tensioner to get the belt on more easily.
I suspect you will need a different fan too. On my build I had used a 1st gen fan pulley from intercooled diesel a 2nd gen fan hub and a 3rd gen hub bracket which has a mounting tab for reverse rotation idler pulley.
 
I suspect you will need a different fan too. On my build I had used a 1st gen fan pulley from intercooled diesel a 2nd gen fan hub and a 3rd gen hub bracket which has a mounting tab for reverse rotation idler pulley.
I don’t follow. The 1st gen fan pulley on the 2nd gen fan hub/bracket puts the fan pulley way out of line with other puleys. And I’m just saying I wish to get a tensioner pulley that moves to the passenger side instead of driver to relieve belt tension.
 
New Cummins water pump on that engine? Because, yeah, that small pulley spins it fast till the bearings let go... often. It's 2 bolts now vs. drain cooling system later and 2 bolts. Short lived pumps: there will be a later regardless. :banghead:

Doing anything else to the engine itself aside of paint?

How about the fuel system? Getting one of the accurate and bomb-proof fuel level sensors put in the tank? Lift pump?
 
No water pump yet. I’ll snag one. Engine is stock as far as I know. Gonna have a local Cummins shop get the IP inspected to see what if anything has been done. I have a FASS pump and a new sender. Everything will be AN fittings.
 
I don’t follow. The 1st gen fan pulley on the 2nd gen fan hub/bracket puts the fan pulley way out of line with other puleys. And I’m just saying I wish to get a tensioner pulley that moves to the passenger side instead of driver to relieve belt tension.
"3rd Gen bracket" is what I used and it all lines up just fine been driving it since Jan this year..................see the images in my build .
 
I'm still waiting for a project to get moved out of the way of the space I'm renting in a friend's shop so I can get to the real work.

Untitled by mariley85, on Flickr
I'm sure it will be a work of art........as for my fan setup people in the Cummins community said my combination of parts from 1st, 2nd & 3rd gen would not work however; they did but then again I'm using the FORD CUMMINS midmount AC compressor mount!
 
Fan clutch life is 5 years.
Not sure if new one is in the plans now, or if that was new before you painted it- if so...
start carefully dabbing the paint remover on the bimetal spring of the fan clutch now. paint will mess up it's operation, I learned this the hard way years ago. What did I learn after that? That if you get a strong paint remover on the tiny seal on the shaft, it will destroy it quickly and a new fan clutch turns into paper weight with in a year. ensure you get all the paint in between the coils.

Nice looking truck btw. I get the attraction of the 12v p pump. I had a hard time not stuffing one in my hummer when I had the chance.
 
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