454 blown intake gasket? Just add Diesel!

[jbclassix]

Let's just throw this out there:

We needed a suburban. It had to be 4x4 3/4T and clean. This one fit the bill, but the intake gasket was toast.

Diesel should fix that leak...

[jbclassix]

Just some left over parts from some previous swaps 6.5l/4L80E/4401

I know its 100 horsies less than the 454, but 10 miles to the gallon better.



It also came with the NP243 which is the electric shift... well, it had most of a 243. The funny thing was that this t-case still shifted and worked fine...

[Dieselwrencher]

Nice new burb! That tcase was on borrowed time for sure!

[jbclassix]

thanks Ryan! I did put the lethargic 6.5L to the test moving from CA back to CO. Still have a few bugs to work out. I used a 98 engine harness and a 97 dash harness and while they plugged in to each other, the wiring is different. I got the essentials working like most lights, oil pressure temp tach and fuel.

the speedo doesn't work, and the high beams activate the front wipers... then I need to get the ac working.

[justcuz]

What is the torque rating of both engines?
Those 3/4 ton Suburbans do make nice tow vehicles.

[jbclassix]

Originally Posted by justcuz

What is the torque rating of both engines?
Those 3/4 ton Suburbans do make nice tow vehicles.

Happy father's day!

the 454 and 6.5L are closely rated for torque. the 454 is rated at 410 and the 6.5L is 400ish... gears make a difference for both engines. the 4.10s let the 6.5l tow, but at the higher RPMS the tiny turbo chokes. I put in 3.73s because I am after mileage, but they also keep the RPMS low and I think tow just as well if you know what you're doing. If I wasn't planning on taking long trips in the suburban I would have left the 454. the white suburban above is my brothers. it's got the 454 and it's gonna get the old 454 out of my burb once it's been rebuilt. his 454 gets the same mileage unloaded or towing. those things are awesome beasts. the only thing his burb lacks is clean leather. it is fully optioned, but the front seats are toast. Once I have the bugs worked out of the Suburple I've got some tricks to throw at it and see what kind of mileage I can get and if I can keep EGTS manageable... that was my biggest challenge towing over the I70 corridor.

[justcuz]

Happy Fathers Day to you as well, hope it was a good one. How can you miss with 4 children? 4 was our goal, but we settled for 2.

Funny about the gears 3.73 is only 10% higher than 4.10's would not think it mattered that much.

You can buy replacement leather and install it on the seat frames yourself.

Hoping you throw some pictures together and start a thread on this Suburban.

Read my comments in your Yukon thread about the Sequioa, a man of your talents should be able to pull it off easy.

[Dieselwrencher]

The outlet plate is the same I believe. I have one of each and I'll try to lay them together and get back to you. Are you going to try to push the crank out of the block so soon on the ol gm diesel?

[justcuz]

I'm not a diesel guy, but I thought bigger exhaust, water or alcohol injection or an intercooler lowered EGTs. Increasing turbo size and flow is packing more air into the combustion process which would tend to raise EGTs, or am I missing something?

[jbclassix]

Originally Posted by Dieselwrencher

The outlet plate is the same I believe. I have one of each and I'll try to lay them together and get back to you. Are you going to try to push the crank out of the block so soon on the ol gm diesel?

Shouldn't be building any more boost, hopefully. I just want to keep the EGT's down going over Colorado's little hills. I am modifying the stock wastegate controller to work on the HX40 as well.

Originally Posted by justcuz

I'm not a diesel guy, but I thought bigger exhaust, water or alcohol injection or an intercooler lowered EGTs. Increasing turbo size and flow is packing more air into the combustion process which would tend to raise EGTs, or am I missing something?

The Turbo on the 6.5's is tiny. At sustained RPM's the turbo becomes like a restriction in the exhaust which builds heat. An intercooler, and WMI are in the works, just not the budget at the moment as well.

[justcuz]

Thanks for that, I learned something new.
I always thought smaller turbos spooled up faster giving power at lower RPMs. Never thought about outlet size.
I know some turbos come apart so you can change the inlet and exhaust positions, would that allow mixing of housings to change intake and exhaust sizes? Does an increase in turbo size increase the size of everything?

[jbclassix]

you are correct. small turbos spool up quicker and produce power at lower engine rpms, but anything over 65mph and the poor little gm turbo is like breathing through a straw while working out. I've thought about hybrid holset set ups using 35 and 40 parts, I've looked at other Garrett and IHI options as well as Cat, but in the end it came down to what I found on craigslist in my price range.

[Dieselwrencher]

HE341 or HY35 might be an option too. Should be cheap because all the dodge guys take them off to upgrade.

[jbclassix]

This truck was built from mostly used parts... including the exhaust off of 4 trucks. The down pipe was my 3" from diamond eye that I had on the crew cab, but I hacked that, again, to bring it up to 4" a few inches before most. A lot of the exhaust is 4" off a Duramax. They used a different coating other than aluminum so it appears brown, but it is not rust, and welds nicer than aluminized. the Muffler came off an Excursion, and the tail pipe came off a F450. I set the muffler as far forward as I could, which is one of my tricks for a real deep exhaust note. I need to finish the exhaust by bringing it out from under the body. I literally ran out of pipe, and time, otherwise it would have been done before I installed it. I guess I will just find a clamp on tip. You will also notice I left the floor heat shield from the 454 on the passenger side. The 6.5L trucks didn't have this, but it clears and just makes sense, so it stayed.







I did tuck the exhaust up and as close to the frame as I could get it so that nothing hangs below the frame rails for wheeling purposes. In the past I have had big problems with down pipes interfering with the #6 glow plug wire, and in the crew, this DP and the glow plug heat shield sandwiched the wire, which ended up melting, again. I re-worked the heat shield to bend and clear the DP. You will notice that the heat shield is turned and only mounted with one of the bolt holes. So far it works like a charm. Well, at least here. Somehow I missed part of the glow plug harness when I was tying everything up, and part of the loom was too close to the DP. I don't have my pyrometer hooked up yet, but I know I got my EGTs up there going over Vail pass and going up to the tunnels. There was no damage to the harness, and I am thinking this was some el cheapo loom I had left over from removing some audio accessories.





I was cautious about heat shielding everywhere else. The glow plug wires and the heater hoses got sleeves, and the rear AC lines got heat barrier matting. You can also see my hasty heater "T" fix.





With this being a 96, the windshield washer reservoir was where I had the remote PMD originally, so, against my will I relocated it to the inside of the bumper, but gave it a little more protection than most, as well as a little more air flow than most. The best of a compromise, I would say.



The only t-case I had to replace the NP243 was a BW4401, which is what came in the K3500's. It has a fixed rear output, and a PTO mount. Other than that, I don't know if it is any better than the NP241. Using the BW does require a different torsion bar cross member which is not straight across like the NP cross member.





For a driveshaft, I found a stock rear driveshaft from a 73-82 K20 that had a SM465 with the NP203 (not 205!) that was the perfect length. I also found that 85 and 86 F250 RCLB, but Ford doesn't use a conventional u-joint. I was real happy to find this driveshaft, and it was the last thing I did before I hooked to the trailer to move!



Here is one of the little things that can cause havoc on a swap, and sometimes gets overlooked. Diesel caps (and the ones from parts stores aren't right) vent different than gas caps. I need to find the pictures of what I did to modify the 454 fuel tank for diesel still.



I swapped in the diesel cluster that came from the vehicle that donated the motor, and this is where I am at on the swap. I used a 97 dash harness, and a 98 engine harness, so the speed sensor signal is lost somewhere... I got the oil, temp, fuel, and charge gauges working before I left. I figured those were important because I didn't think I was going to be able to speed (especially through Utah) pulling the trailer. The SES light is because I haven't set the TDCO yet... Gotta get to that too.





This is our LEAST favorite part of the truck. Luckily the left one is broken so I get to put the boring ones back in.



One one of our trips back from Cahone I blew the left rear tire to pieces up by Blue Mesa Reservoir and it did some damage to the fender and body... boo hoo... Im just glad the family was ok, and I dont really care about the body on this, but I will secure the flare back to the body.

[marvgarr68]

Nice job! Use the Hx40 on the Hx35 exhaust housing. Your egt should lower quite a bit. Looks like it is getting nice and hot.

[justcuz]

Nice job on the parts combo to make it all work.
Does that rear axle have the 13" drums?

I saw a green and silver 3/4 ton diesel in the high desert a few weeks back and turned around to go look at it. Tan leather, I was stoked.
My wife looked at me and said really? Where do you propose to park this one?
Our drive way is full, the side yard is full and I have two vehicles in my back yard.
I can dream though!

[jbclassix]

Originally Posted by justcuz

Nice job on the parts combo to make it all work.
Does that rear axle have the 13" drums?

I saw a green and silver 3/4 ton diesel in the high desert a few weeks back and turned around to go look at it. Tan leather, I was stoked.
My wife looked at me and said really? Where do you propose to park this one?
Our drive way is full, the side yard is full and I have two vehicles in my back yard.
I can dream though!

yes, it has the 13x3.5 drums
If you ever come across a smokin deal on a 96-99 burb with a mint interior, my brother's is toast and he lives up in the antelope valley still

Well... I am pretty sure that somehow all the pictures from the build got deleted... bummer.

[Dieselwrencher]

Nice work on that exhaust! How can they make you add a soot trap to an engine that was never designed with one? Are you calling a catalytic converter a soot trap? I wouldn't be surprised if CA does try something like this but from what I've read and know they will just not allow the vehicle to be registered if it can not pass a sniff test and smoke test. But those laws/regulations seem to be constantly changing out there.

[jbclassix]

update: speed signal works! GM wire diagrams are hard to navigate from year to year, but I found what I was looking for and got everything cobbled together. not my finest, but it works. I didn't pull and swap wires just so I would have something to reference just in case I lose the info on how I got it to work. if you look at the top of the first picture you can see 3 splices that go across the dash to the connector in the second picture. this would now be the signal input for fuel level, water temp, and oil pressure. toward the bottom of the first picture you can see two more splices into a twisted pair. this would be the output shaft speed signal, connected now to what would have been gauge wiring for 98 models. and... if you look in the back ground, you can see a BBQ issue needing adressed... later.

Originally Posted by Dieselwrencher

Nice work on that exhaust! How can they make you add a soot trap to an engine that was never designed with one? Are you calling a catalytic converter a soot trap? I wouldn't be surprised if CA does try something like this but from what I've read and know they will just not allow the vehicle to be registered if it can not pass a sniff test and smoke test. But those laws/regulations seem to be constantly changing out there.

believe it or not, CA is actually more lenient on 97 and down diesels than CO. we'll find out what I need to pass emissions. and GM was ahead of the game when it came to choking diesels. in 96 they introduced a soot trap in the exhaust, easily mistaken for a catalytic converter. on the 1/2 ton diesels they also had back pressure fed egr, sans cooler, and it should have been taken as a warning to all that egr just kills diesels.


for some reason, my pictures did not rotate right......

[Dieselwrencher]

Good to know on the soot traps. I'm sure I have seen some in the scrap bin and assumed they were cats.

[deejaaa1]

nice build!

[jbclassix]

most recent update: the dorman part to install the 98 style front axle actuator on a 97 is stupid expensive... the GM (15002405) is much more reasonable. there is also a conversion harness from GM but I don't have that part number. didn't need it.

[jbclassix]

Trip update: loaded the family for a week visit to one of my least favorite states. Good thing the burb got new tires and the 4wd worked since we needed it over the Rockies. Fuel wise, it did ok at 17mpg average. It was a nice ride there and back. Looking forward to some mods this summer once the 2wd Toyota can haul the family again.