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HippyJoDiesel

HippyJoDiesel

Onion Bhaji
Joined
Aug 6, 2020
Member Number
2586
Messages
23
So, with the way prices are going just now, I'm wondering if it's even worth sticking the 6.2 diesel in my squarebody.

The idea had been something to chug around the back roads, and the fact, I really don't like gas motors, too much farting about with electricity.

Now with diesel a good buck and a half more than gas, I'm wondering whether it's worth the effort.

Anyone know how / if a 6.2 will run on veggie oil? That might make it worth the time.

It's an old Suburban with a locked up 350, that's been filled with diesel the last half dozen years or so, to try and free it up, and I do mean filled there's about 12 gallons in there, minus what's evaporated. I picked up the 6.2 cheap, with torque converter, and vacuum stuff, from a guy who was converting in the other direction.
 
My experience with the 6.2 is both good and bad. They are thrifty on fuel, 15+mpg is easily attainable. Some people report over 20. But they have some upkeep. They are hard starters when the glow plug system isn't working. Make sure the starter bolts are tight as well as the support bracket. Hope that your injection pump is healthy on your takeout. Check the harmonic balancer.

When everything is in good shape they are good engines and will get you where you need to go while sipping fuel. But they can also nickel and dime you to death once things start going bad.

How many miles you going to put on a year? Is the fuel cost savings(if any) really going to matter vs finding a cheap small block that will just drop right in?

As far as the veggie oil idea. I've heard stories of it working, and stories of it completely wrecking the fuel injection system. A lot of that depends on how clean and dry your veg is.
 
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HippyJoDiesel said:
So, with the way prices are going just now, I'm wondering if it's even worth sticking the 6.2 diesel in my squarebody.

The idea had been something to chug around the back roads, and the fact, I really don't like gas motors, too much farting about with electricity.

Now with diesel a good buck and a half more than gas, I'm wondering whether it's worth the effort.

Anyone know how / if a 6.2 will run on veggie oil? That might make it worth the time.

It's an old Suburban with a locked up 350, that's been filled with diesel the last half dozen years or so, to try and free it up, and I do mean filled there's about 12 gallons in there, minus what's evaporated. I picked up the 6.2 cheap, with torque converter, and vacuum stuff, from a guy who was converting in the other direction.
Click to expand...
Umm

What are you saying?
 
If it's a th400, forget about it. Absolute slug and not great economy.
 
slap it in and drive it til it won't no more. not fast but as long as you're not pulling a big trailer it'll be ok. I have a burb here that I'd drop another 6.2 in if I had a good one. I always got 17 out of my crewcab with a 6.2/th400 combo.
 
I have a 6.2 in a CUCV. I love driving it but it's mostly useless except for just driving around. Absolutely not with a TH400. I now have a 4L80 which I tuned so it shifts way quicker then the factory ECU which helps keeping the 6.2 where it needs to be.

I will say it will cruise now at 80mph no prob with the AC on but that's around sea level on flat ground. Get on a grade, have to pass someone, or up higher and it quickly turns into a boat anchor.

Mine has been trouble free for over the decade I've owned it. It comes out of storage from winter, hook the battery up, bump the key and it purrs like a kitten. I've driven it up and down the east coast. I would never hesitate to get in and go wherever. You'll always arrive, just way later then everyone else.

Having said that I've wasted time swapping one into another project and that now has an 8.1 because the other 6.2 was nothing but trouble which ended with a crack in the block.

It's a love hate relationship...
 
V30crewcab said:
I have a burb here that I'd drop another 6.2 in if I had a good one. I always got 17 out of my crewcab with a 6.2/th400 combo.
Click to expand...

My Burb got only 12mpg with 4.10. :barf:

Improved to 17 after sm465 and 3.21 swap.
 
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Yeah, guess I wasn't real clear. I got the diesel silly cheap, like $100, so I grabbed it.

My dilemma is whether to just pull the 350 for the 6.2, or try and get the 350 running again, seeing as gas is way cheaper. I mean the 350 has been soaking many years now, it's a long term project. I don't need it running, if I get it running, probably use it for lumber runs and camping.

I've got the 700R4 AFAIK.
 
Ordered stage2 rebuild kit and B&M kit...

Called around and $3500.00 round me apparently is the majik rape #....

I rebuilt a BigBlock C6 4x4 transmission years ago.. so wtf..why not.

Rebuild the 700r4 4x4 in my Suburban.

What I'm saving is going straight toward a egine.. just do all work myself..
 
Trying to get an old siezed engine running will probably result in a fuel sucking gutless turd.

Swapping in the 6.2 feels silly, but at the same time, if you got it for basically nothing, know it runs and don't need much power, it's probably fine. I don't think it's much of a "swap" anyway.
 
What about a 454 with decent top end and cammed? Its gonna be a gas guzzler, but a lot more fun to drive. It’s a suburban after all.
 
I would look more favourably on the th700 with the 6.2. Lower 1st gear, OD, and lockup are a big help vs the th400.
 
12yr with diesel is a long time. It'll probably free up nicely as long as it's not so rusted that there's tons of interference holding shit together.
 
If cheap is part of the idea, just toss an old 4.8 or 5.3 in it. More power and close to the same mileage.
 
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ls swap is not cheap. wiring, fuel, gaskets, motor mount adapters. I've done several and they're never cheap, or quick.
 
I did all of those things myself when I did swaps. Seems no more difficult or costly than going from old 350 to old diesel.

Your results may very...
 
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Honestly my choices are:

The 350 in it.
The 6.2, I already own, sitting beside it.

Mainly cause they are both there, and will both (allegedly) fit it. It's a rust belt squarebody.
 
I've always liked the 6.2's and have one sitting to go into my 1963 GMC project. That being said the TH400 was a big holdback to these things from stock and I think one of the reasons people don't like them originally. The 700R4 you have while not exactly a stellar transmission is a better fit with the lower first to help it get moving and the OD for on open rd. I have had them with TH400 and swapped to a SM465 after having a light GVW 2500 with that combo and love the setup. Biggest deal for me is set up a manual glow plug circuit and if thinking about WVO or WMO filter it well and run a good water separator not the junk box on firewall they came with. Also I'm sure you know but once you start running either in the truck never mix the two, it creates a horrible sludge that will destroy the IP but individually they are both fine when filtered good.

There are also ton of youtube vids on mixing a thinner into WVO to make it flow closer to diesel. Some people just use diesel,kerosene or ethanol free gasoline to thin it a bit and install a low pressure electric fuel pump near tank so the mechanical pump is working too hard to suck up the heavier\thicker fuel.
 
Beware that the 700r4 kickdown bracket for the 6.2 is now made from unobtanium...
 
350TacoZilla said:
Biggest deal for me is set up a manual glow plug circuit and if thinking about WVO or WMO filter it well and run a good water separator not the junk box on firewall they came with. Also I'm sure you know but once you start running either in the truck never mix the two, it creates a horrible sludge that will destroy the IP but individually they are both fine when filtered good.

There are also ton of youtube vids on mixing a thinner into WVO to make it flow closer to diesel. Some people just use diesel,kerosene or ethanol free gasoline to thin it a bit and install a low pressure electric fuel pump near tank so the mechanical pump is working too hard to suck up the heavier\thicker fuel.
Click to expand...
The manual glow is not an issue, I'd just planned to do something like a momentary switch and a Ford solenoid for the glow plugs, I'm learning, last time I used a SPDT switch, and the number of damn times I left the glows on all the time and flattened the battery I don't recall (this was on a VW).

I hadn't heard of not mixing the two? I thought it was common practice to have a main tank of WVO and a starter tank of diesel, and just flush the system at the end of each journey by flicking it over, manually or otherwise, which would mean the WVO and diesel would meet in the fuel lines. This being cause you need something to heat the WVO, usually engine coolant, unless you have some kind of electric immersion heater and can leave it plugged in at each end of your journey?

Anyway, not arguing, just inquiring, I'm not at the point where I'm talking to local diners BUT when a bunch of guys in the middle east can choose to withhold oil to stabilize the price (read: steadily increase), I start looking around, and EV's still don't have the infrastructure or range for us rural folks. I liked the idea CAT had in their early demos, where they would harvest then press soybeans, and then run their tractors on it, I'm in the corn/soy belt, use what you got. Suppose I could rejet the carb for ethanol too tho'. The carb is toast anyways.
 
I'd just throw a junkyard 5.7 in it and be driving in a weekend. You'll never recoup the money of having to swap another engine in. Unless of course you have a complete free donor truck with a 6.2 that runs.

But I love old shitty IDI engines 🤣

Build an EV truck then use a wood gas generator or burn waste oil in an old diesel generator to charge it. Best of both worlds 😎
 
Skinny said:
Beware that the 700r4 kickdown bracket for the 6.2 is now made from unobtanium...
Click to expand...

HippyJoDiesel said:
Did not know that, errm.
Click to expand...

If you need one, cover the cost of a set of intake gaskets and shipping and I'll pull it off my 84 6.2. (I think the intake has to come off, I'll try without it first).

Was a 6.2/700R4 and I've swapped to an NV4500 after blowing up the 700R4. Left the linkage on the engine.

I probably have some wiring and shift linkage laying around as well. I'll look on Saturday when I'm back at the shop.


And for the record, I love my 6.2. Granted it's in a 2wd short bed, but my expectations are realistic and it's been a good driver with awesome fuel mileage. If it blows up, I'll just toss another one in.
IMG_20210910_090056.jpg
 
Ive been waiting for mine to blow up so I can go with an Optimizer or P400.

Yeah that's been over ten years and still nothing 🤣

Granted mine is NA and I taker er easy.
 
If you can source one snatch it up. A lot of people on Steel Soldiers would probably be interested as all those trucks have TH400 and most with 4.56 axle gears.

The 700r4 is an easy swap in those...with that bracket.
 
M92PV4U said:
www.ebay.com

6.2 diesel TRANSMISSON kickdown bracket cable 700R4 4l60 | eBay

Find many great new & used options and get the best deals for 6.2 diesel TRANSMISSON kickdown bracket cable 700R4 4l60 at the best online prices at eBay! Free shipping for many products!
www.ebay.com

:eek:
Click to expand...
$25 bracket.

$300 fee for being too proud to make one using cardboard CAD and whatever 1/8 material is in your scrap pile.

Even at $100 out the door I'd be thinking about making my own but $300+ and it's not even a choice. :laughing:
 
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