filthyrich New Reader
Sept. 18, 2015 12:58 a.m.

Hi guys, just want to share a 4BT swap build I did in an '04 Chevy Tahoe.

Full Album

"Bringing it back from the dead" Bought an 04 loaded Tahoe with a blown 5.3L. Previous owner hit a tree so it needed a bumper and hood as well.

"4 Bore turbo Aftercooled (4BTA)" picked up 2 4BTs with nv4500 transmissions as a package. Sold both Trans and 1 engine and paid for the whole package. Had a scrap 5.9L as a donor for things like exhaust and vertical oil filter housings.

Got a flywheel from Diesel Conversion Speacialists but after checking mating with the torque convertor realized they didn't mate, so I made my own holes. Problem solved

Welded the end of the 5.9l manifold shut and relocated the Turbo to leave room for the AC receiver dryer.

"Sending Unit" Dug into the vortec and got the Crank sending gear off the crank. Machined a pulley and heat shrunk it on to put in in front of the vibration Dampener.

Dry fit. So far so good.

Clearances were ok. Had to take little cooling fins off the front diff to make the oil pan clear

Tight but fit very well

Video series:

3.9L Cummins 4BT in an '04 Tahoe (Part 1)

3.9L Cummins 4BT in an '04 Tahoe (Part 2)

3.9L Cummins 4BT in an '04 Tahoe (Part 3)

FIRST START: 3.9L Cummins 4BT in an '04 Tahoe (Part 4)

3.9L Cummins 4BT in an '04 Tahoe (Part 5)

3.9L Cummins 4BT in an '04 Tahoe (Part 6)

3.9L Cummins 4BT in an '04 Tahoe (Part 7)

FIRST DRIVE: 3.9L Cummins 4BT in an '04 Tahoe (Part 8)

TUNING: 3.9L Cummins 4BT in an '04 Tahoe (Part 9)

RUNAWAY? 3.9L Cummins 4BT in an '04 Tahoe (Part 10)

Why I Put a 3.9L Cummins 4BT in an '04 Tahoe (Part 11)

"Biodiesel" Haven't tried it yet, next summer's project. Biggest cost of making biodiesel is getting it up to 55 Celcius. Its a perfect fit for the greenhouse as I don't have a green thumb--they are always black. Should be able to make Diesel at 40 C/L compared to $1.10 at the pumps

"Headrest Monitors" Got some headrest monitors for the kids.

Love the 2500HD clip. It was already white so I didn't have to paint it.

Got some nice rims from the neighbour kid. Dressed with lt285/75R16 BFG's

Gotta have the badging so people don't think I threw 6 rods in the vortec

"Engine Bay" Put all the shrouds back on cleaned her up

Very happy with the project. I am getting mid 20's mpg. This should bring my fuel savings from about 8000/yr down to about 4000. Hoping to save another 1-2000 with the biodiesel, as its not up and running yet. I would do it again in a heartbeat

Putting her to work. Tows like a boss.

The_Jed UberDork
Sept. 18, 2015 2:16 a.m.


ebonyandivory UltraDork
Sept. 18, 2015 6:10 a.m.

I have a 2005 with the 6.0 and this piques my interest.

Love the front end conversion too!

bgkast UberDork
Sept. 18, 2015 9:21 a.m.

Nice work. How is access to cylinders 3 and 4?

singleslammer UberDork
Sept. 18, 2015 9:29 a.m.

In reply to bgkast:

Looks about as good as access to the rear cylinders in a Jag XJS

2002maniac Dork
Sept. 18, 2015 9:56 a.m.

Sweet conversion! Are you running the original 4L60E trans? Do you expect it to survive?

I would love a rattly diesel in my 2500 burban.

filthyrich New Reader
Sept. 18, 2015 11:11 a.m.

In reply to bgkast: Not bad at all. One bolt per valve cover. Everything has just been done to it including a valve set so it shouldn't need anything for 50 000km or so!

filthyrich New Reader
Sept. 18, 2015 11:13 a.m.

In reply to 2002maniac: I added a massive cooler and keep a close eye on the temps. I pulled a 2004 Murano behind it on a tandem and the temp never got higher than 180*. Heat destroys everything so gotta keep it cool

java230 Reader
Sept. 18, 2015 11:56 a.m.

This is fantastic.

conesare2seconds HalfDork
Sept. 18, 2015 7:58 p.m.

Wait, what? This build is bonkers. And very cool. Thanks for posting.

wheelsmithy HalfDork
Sept. 19, 2015 9:22 a.m.


filthyrich New Reader
Jan. 19, 2016 3:28 p.m.

Part 12: Back with a new update on the Tahoe! Finally got the Holset HE221w Turbo to try to get some more boost out of this beast. Watch more episodes of the 4BT Tahoe build

00:06 Holset HE221w Series Turbo

02:59 Turbo Assembly Overview

05:42 Priming The Turbo

06:43 Boost Test

07:11 Turbo Test Drive

09:50 0-80km/hr Test 1

10:30 0-80km/hr Test 2

jgrewe Reader
Jan. 19, 2016 3:48 p.m.

This is awesome. I've had thoughts of putting one of these engines in something like a Jeep CJ.

I made bio for about 6 years and ran my Cummins powered Ram over 100K miles on 100% bio. Truck loved it, it kept everything in the fuel system clean and the oil didn't turn that coal black anymore. You will lose about 10% on your mileage but when it costs so much less you won't care. Come look me up here when you are ready to start brewing. As for the people that will say, "You'll hurt your engine!" My truck is about to turn over 300K miles and I just drove it to Ohio and back for Thanksgiving and never gave it a second thought.

My processor is up on a pallet rack right now because fuel is so cheap. If it starts going up again I'll pull it down and fire it up. My cost ended up being around 70-80 cents a gallon on average. There was a spike in methanol prices a while back but I never had more than a dollar a gallon when people were paying $4.50.

filthyrich New Reader
Jan. 26, 2016 4:05 p.m.

Where are you from? I definately could definately use some guidance on making Bio. Thanks for the input!

crankwalk Dork
Jan. 26, 2016 4:20 p.m.

I love everything about this build. As far as biodiesel goes, a modern VW with a DPF and sensitive HPFP I wouldn't go more than 20%. But on a 4bt , I'd run bio in a minute and not think twice. It doesn't care.

singleslammer UberDork
Jan. 26, 2016 4:25 p.m.

In reply to filthyrich:

What sort of fuel mileage are you getting? (Side note, do you use US or English gallons?)

AntiArrhythmic New Reader
Jan. 26, 2016 4:38 p.m.

My buddy has a dual tank setup in his F-250 Powerstroke with the grease car kit. He runs straight WVO with no problems. He's had it like this for a couple of years. He also has several diesel benz's that he runs on WVO. The heated oil runs thru a big ass oil filter before it gets to the engine. He does have to change the filter rather frequently.

Jan. 26, 2016 7:11 p.m.

This. This is why I love this nutball forum.

RossD UltimaDork
Jan. 27, 2016 7:50 a.m.

So what kind of power output do you suspect you're making? Does the truck feel slower than when it would have had the Vortec?

golfduke Reader
Jan. 27, 2016 12:13 p.m.

This is amazing. Weight discrepancy of the longblocks/accessories between the 4BT and old 5.3? Estimates are cool too. My interest is heavily piqued. Would make an absolutely badass tow rig.

maschinenbau Reader
Jan. 27, 2016 1:07 p.m.

I see you did a cat delete

java230 HalfDork
Jan. 27, 2016 1:11 p.m.
golfduke wrote: This is amazing. Weight discrepancy of the longblocks/accessories between the 4BT and old 5.3? Estimates are cool too. My interest is heavily piqued. Would make an absolutely badass tow rig.

From cummins 4BT:
745 - 782 lbs w/ oil

From interwebs: Iron Block vortec 580, alum 500.

In reply to maschinenbau:

I LOL'ed

filthyrich New Reader
July 25, 2016 11:25 a.m.

Part 13: Mileage Update - loaded up some trailers to see how the Tahoe handles it, then got some mileage numbers while on vacation. Watch more episodes of the 4BT Tahoe build

00:06 Trailer full of fencing

00:35 Getting Weighed

01:38 Trans & EGTs Towing 13000 lbs

02:15 Trans & EGTs Towing Silverado

03:02 Let's Figure Out Mileage

03:58 Tahoe Mileage Update

jgrewe Reader
July 25, 2016 8:31 p.m.

Sorry I didn't see the location question until this came back to the top. I'm in St Petersburg, Fl but I could get you making great fuel over the web no problem. Or if you come south like so many others from the Great White North we can do a bio fuel fantasy camp this winter.

One thing about Bio it will cloud at a much higher temp than dino-diesel and clog a fuel filter right up. Not a winter fuel for you for sure. So maybe June to Aug?

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