Advice on putting a 6.2 diesel in a 72' K10

[Truck Hippy]

I did several searches on diesels in 67-72 trucks but I didn't find what I was looking for. I know this has been done so I want to ask some questions. My goal is 30 mpg in a 72' swb 4x4. I sold my 72' swb 4x4 over a year ago and I'm having withdrawal. It wasn't anything special. It was rusty and beat up but it still got a thumbs up from a lot of people but the 350 was a gas hog. I'm half way looking for another one to drive and I want to put a 6.2 GM diesel in it. My questions are to the people who did it are,
1, Did you regret it
2, Did you have to put sound proofing on the firewall
3, Did you have over heating problems with the factory radiator

I have other questions but this is the most pressing right now. The reason I'm looking at the 6.2 is I don't want to hack a truck up and I would like to be able to change to a 350 in a weekend. Please post your comments either for or against. Good or bad, Lets hear it.

[Longhorn Man]

If you must go with anything of that family, I'd say go with a 6.5 with a turbo. I still doubt you'd get 30 MPG, but that'll probably get the best out of that family of engines.

[Stocker]

Based on a company 1-ton service truck (several years ago) with the 6.2, I wouldn't waste my time. Slow, weak, noisy (even for a diesel), sometimes hard to start...

I'm not familiar with the 6.5 turbo, but it must be better.

[JAKES 68GMC]

yeah don't even frig with the 6.2's. Peterson's 4-Wheel and Off-Road magazine had one in a 80-something K30. They said it was slow, and they put a turbo on it, and it was STILL slow.

The 6.5's are better engines, all the ones I've seen have over 150k miles on them and still run great.

[Spray-Bomb]

I have to agree & disagree with the 6.2 being a "dog"

We used to have one that was "turned up" & it ran pretty good, But IMO the 6.5 TD is better

But don't think you're gonna get a bunch of power out of one & you definitely won't get your 30 MPG, if you're lucky you'll get 20 somethin

Also the earlier 6.5's had overheating problems, so you need to find a 96 or 97 (can't remember which) as they have a better cooling system (fan, water pump, ect)

If it were me, I wouldn't put a 6.2 or a 6.5 in anything
Save your money & get a Duramax

Just my .02

[72 CustomCamper]

I had a 6.2 in my C/20. 700R4 trans and 4:11 in the dana 60 rear. I would get about 22 MPG. As for everybody saying about it being a dog,I say wrong. This truck would haul a**. 1st gear would fry the tires, and when it hit 2nd it would fly...


Chuck

[Longhorn Man]

I've never hit the skinny pedal and smiled in any truck powered by any one of those engines.
I was gonna keep my turd comments to myself

[Stocker]

Originally Posted by Longhorn Man

I've never hit the skinny pedal and smiled in any truck powered by any one of those engines.
I was gonna keep my turd comments to myself

[Truck Hippy]

I have never owned a 6.2 diesel truck but my buddy has. He had a 85' Silverado with a 6.2 and it was ok. Not a hot rod but he said it could get 25-26 mpg with out much effort. I'm not really interested in making a powerful pulling truck.

[Basicfish]

I own a 1995 c3500 dually with the 6.5 turbo, and i had a 6.2 burb for about 3 years. the burb got about 22 mpg and I pulled a 24 foot wellcraft fishing boat with it. It had good power about like a 305 or a two barrel 350, It would no out run my 5.0 Mustang but it would do 70 mph all day long and get about 20-22 mpg. Now the 95 6.5turbo I own gets about 16-17 combined driving at 70mph. The 3500 alot of carrying and towing capacity but it has the power of a stock 454. Now the 6.5 and 6.2 series of engines were designed by detroit diesel for the light truck line as a good mpg lite duty engine. Its down fall was that chevy marketed it as a competor to the Dodge/Cummins or the Powerstroke. People would buy them down here in Texas and try to pull a 30' gooseneck with four round bails of hay then get mad when the engine would go out in less then a year. It is a good engine if you remember what it capable of. In a 1/2 ton the 6.2l with the mechanical injection pump will be as easy an any other carb swap.The 6.2l came in pickups,burbs and blazers so putting one in a 67-72 should be simple. Now a 6.5l turbo will be a as hard as putting a 5.3 gas in one. The turbo is just a ploy by GM it's not intercooled and has only about 3-5 pounds of boost and if you turn up a stock one you will get the EGT too high and burn up the motor. The bottom line is find a 6.2l in a rusted out truck and you will get all of the parts cheep. But if you want to rebuild an engine for your build it will cost a lot of money. I have owned one of these trucks since 1995 the 6.2 burb only had old truck issues. but the 3500 had to have it's electronic injection pump replaced 3 times all paid for by GM , at about 3 thousand dollars each! If it was comming out of my pocket I would have sold it a long time ago. If you really want to go diesel look at thedieselpage.com or dieselplace.com for good info on the GM diesel engines I has saved me a alot of time and money over the years.
take care
Ron

[jeffspower]

6.2's are OK for light duty. 6.5's are tougher, but not by much. If you use either of them hard, they won't last. But it can be a luck of the draw too. I have wrenched on 100's of them. One guy might abuse his hard for 300k without problems, while another guy never hooks to a trailer or breaks 55 MPH with his and it blows up. Quality control when casting these must have been non- existent.

Here's some things I have seen repeatedly:

-Crankshafts that twist off at the flywheel on man. trans. applications

-Blocks that crack from the #4 main bearing all the way up to the cam bearing. The cam bearing then slips out of the bore, and results in no oil pressure.

-Glow plugs that burn out may "drop" the tips down into the cylinder. Ouch! Usually, this is from the controller sticking, "holding" the power to them too long & burning them out. When this happens, it makes the glow plugs all but impossible to remove, because the tip balloons from overheating, if it doesn't burn off. Many hours of work trying to dig the pieces out thru the injector hole isn't fun. I've done all 8 glow plugs, the controller & the temp. inhibitor switch all at once to make sure it wouldn't happen again, to HAVE it happen again over & over. Went thru this BS on many customer's trucks. Some people give up, put in a pushbutton, or unplug them & use starting fluid. But starting fluid almost guarantees the block crack/ cam bearing BS.

- head gaskets. Coolant isn't a good thing to have in a cylinder or in the oil. Wait to fix it a little too long, and you end up with scrap iron. It's a horrible job to do in the truck, and costly if you don't want to do it yourself. On a side note, the heads are always cracked between the valves. You rarely find one that isn't. But, the casting is thick enough that the crack rarely opens up into the water jacket, so you can use them. Welding them is a total waste of time- it will just crack again.

-Starter troubles. I could write a book on this one. The "brush end" MUST have the support bracket. Some people chuck it, and then the starter tears off the corner of the block where the outer mounting bolt threads in.

-Stay away from the electronic pumps- total junk. A dependable gas burner that gets 2 MPG will end up cheaper to keep on the road when all the expenses are factored in.

The best (if that term really even applies to these engines) would be the mechanical injection 6.5 Turbo. But they only made it one year, I think it was 1993. I put a low mileage '85 6.2 in a '75 C20 with 4.56 gears & a 700R4 years ago. I loved it until it blew up only a few years after putting it in. Then I put a 500 Caddy in it

[Basicfish]

Jeff, I agree with you If I had to do it all over again I would have paid the 5K more and got the Dodge/Cummins. I just bought a 90 3/4 4x4 Dodge Cummins as a doner for a 67-72 burb project. I think I can build a reliable tow rig daily driver with the Dodge powertrain. And a whole lot less than the 45K for a new truck. I almost forgot' look in to the 4B Cummins , the power of a 350 chevy, and good MPG.
take care
Ron

[Morgsie]

Unless you're going to go Duramax, I wouldn't waste my time with GM diesels. Personally, I'd be going the Cummins route myself. IMO their drive trains are bullet proof. As Basicfish said, the 4B might be the route to go (cheaper too). The mechanical injected cummins should be a no brainer really, aside from motor mounts and tranny mount.

[special-K]

Originally Posted by Longhorn Man

I've never hit the skinny pedal and smiled in any truck powered by any one of those engines.
I was gonna keep my turd comments to myself

Try driving my 300hp 6.5TD.I love droppin`jaws on all the $45,000 diesel newbies.Especially since it leaves a black cloud when I`m on it.The 6.2 and 6.5TD are the same motor with a bit of bore.If you put the turbo parts on a 6.2 you wouldn`t know it wasn`t a 6.5.Also,the 6.2s outlast the 6.5TDs by far.My`91 6.2 Suburban with 4L80E,4.10s,12.50/35 MTRs,and dual 3" exhaust runs great and gets 20-22 mpg.
My`92 sleeper:

[special-K]

Dodge and Ford automatics don`t hold up behind their diesels.That`s part of the drivetrain.I know a ship engineer that has an`82 C/10 shortbed with a built 6.2/naturally aspired that will run circles around a 6.5TD.

[Chevelle454]

Originally Posted by Spray-Bomb

I have to agree & disagree with the 6.2 being a "dog"

We used to have one that was "turned up" & it ran pretty good, But IMO the 6.5 TD is better

But don't think you're gonna get a bunch of power out of one & you definitely won't get your 30 MPG, if you're lucky you'll get 20 somethin

Also the earlier 6.5's had overheating problems, so you need to find a 96 or 97 (can't remember which) as they have a better cooling system (fan, water pump, ect)

If it were me, I wouldn't put a 6.2 or a 6.5 in anything
Save your money & get a Duramax

Just my .02

A Duramax in one of these trucks would be AWESOME. I like to learn everything I can about anything diesel powered. A Duramax engine stock is 360 HP and 660 TQ. Add a PPE programmer with NO other modifications and you can double those numbers. Get into propane injection, water methanol, twin turbo or compound turbos, nitrous, 5-6" exhaust, cold air intakes and stacked chips...you can easily have over 800hp at the rear wheels without making any internal engine mods. And you can make all those mods in one weekend from a stock truck...now I'm getting ideas for mine

[special-K]

I`d love to get my hands on a wrecked Duramax powered GM.Even that will be an expensive proposition.You need to get it all,not like slappin`a Detroit-Allison in.But,they aren`t that great on fuel,especially if you hot rod them.I fear you`d be giving up the longitude benefit,too,with boosting power so much.Then,there`s the third reason for running diesel,simple and economical.Modern diesels have become nothing close to simple.

[Truck Hippy]

I know a Dmax would be very cool in one of these trucks but the cost out weights the benefits with that swap. Not counting the cost of a truck, I think I could swap in a good running 6.2/700r4 for around $2,000-$2500. I thought about the 6.5 but the mileage is not as good as the 6.2 and the turbo wouldn't allow for A/C unless you maybe went with an after market A/C set up.

[Milos7]

I've been looking at the same thing lately. Check out this site for Cummins,

http://www.4btswaps.com/forum/index.php

Cummins repowered a lot of potato chip trucks (Fritos...) with 4 cyl.diesels that used TH400 for trannys.

A 6.2 should bolt in more or less. A friend has a diesel CUCV Blazer and he loves it. He has trouble in the winter due to bad glow plugs though.

[Longhorn Man]

The shop i worked at was a certified Frito lay rebuild center for a few years untill Pepsi-co pulled the plug. There's only a hand full of the $B trucks with the Th400. Most of them are just 4BT. They were pretty anemic. The small block frito trucks would out run them in every area, off the line, top end, passing power, but, the 4BT DID get much better MPG, and I'll assume last longer. However, some of the 4BT parts are stupid expensive. one guy brke an inj pump, and when they said they were gonna make him pay to replace the $8,000 pump, he quite on the spot, told them to get bent.
The 4BTA is the hot ticket. Same engione, but with an air to air cooler out front... this one would hang with the 350 frito trucks neck to neck in every area. (we're talkin small block trucks with 50,000 miles, not fresh and new) If I remember correct, almost all the 4BTA trucks had 4L80E trannys bolted to them. I only remember one with a TH400.
The conversion is fairly straight forward, but the price of admision is pretty high.
Do a search on here for cummins, and you should get a few hits.

[Milos7]

http://67-72chevytrucks.com/vboard/a.../t-185193.html

look over this thread . I hope it helps.

[rdporterjr]

I'm a mechanic for the ARMY. HMMWV or the Hummer for civilians has two engine options one is the 6.2L and the other is the 6.5L TD. The 6.5L will run circles around the 6.2L. That is a much needed asset when hi tailing it from enemy fire.

[72freak]

Dont do it!

[special-K]

The 6.5TD has 60 more bhp than the 6.2NA.Put a turbo on a 6.2 and it will run right with the 6.5TD.The displacement is the difference between a 372 and a 396 with same stroke.It`s all bore.

[eedgell]

Great!! Lets burn some peanut oil!!!!!!!