is a 78 chevy with a diesel rare - The 1947 - Present Chevrolet & GMC Truck Message Board Network

dukes69 · 03-06-2010, 04:30 PM

I am looking at a 78 silverado. The truck has had me confused for a couple days, as i could not figure out what motor is in it. I finally figure it out. it is a 350 diesel. my question is this a rare option? any help on this would be great.

Dukes

Drzronnie · 03-06-2010, 05:58 PM

There are probably a bajillion people who will argue me on this but STAY AWAY. My first job was taking 350 diesels out of cars and putting gas motors in. They are horribly unreliable but I guess if you were just buying it for the novelty factor and didnt have to drive it you would be ok or if the truck is nice just put a 350 gas motor in.

1976K5CHALET · 03-06-2010, 07:03 PM

What he said...ditto!

willett · 03-06-2010, 07:48 PM

i dont think that the made the olds 350 deisel for very long for a reason...
there was a big thread on here about them a month or so ago.

check it out.

dukes69 · 03-06-2010, 08:15 PM

i went and looked at it again and i think it was coverted over to gas, however it still has the diesel block. Am I going crazy?

willett · 03-06-2010, 08:18 PM

same block as a gasser.

don't quote me on this, but i think that its just a matter of switching out the intake, and ignition module

i think that it will have a different cam though.

mrolds88 · 09-06-2015, 12:37 AM

Quote:

Originally Posted by willett

same block as a gasser.

don't quote me on this, but i think that its just a matter of switching out the intake, and ignition module

i think that it will have a different cam though.

Actually the block isn't the same. GM built them with the larger big block main journals. This is part of the reason that racers get the diesel blocks and build them. They are beefier. You can swap to gas. At least cam, heads and ignition system need changed out. Pretty sure a thing or two needs done to the front of the block too as the injection pump drive ran from the front.

*Stitch* · 03-06-2010, 08:51 PM

either way gas or diesel, if it's a 350 that was a diesel stay away...if it's a 6.2l then I say go for it, but it's not so stay away

*jake wells* · 03-07-2010, 03:16 AM

ugh the 350 diesel was not a converted engine it has a thicker heavier block and the main reasons they failed back then was weak head bolts and poor fuel quality and how could it be so bad if its still running and not been swapped to a gasser

78-5.3 · 03-07-2010, 09:20 AM

my 78 was a 350 diesel WAS

Russell · 03-07-2010, 01:10 PM

I've said it a million times before -- Despite some visual similarities, the 350 Olds is NOT a gasoline engine converted to diesel. You CAN NOT install gasoline heads on the diesel block, they are very different. That said, the 350 diesel does indeed deserve it's bad name, it is the 6.2L that does not deserve the 350's reputation.

If the engine is a gasser, then someone swapped in an Olds gasoline engine to replace it

turbo350 · 03-07-2010, 01:35 PM

The diesel of this era has to go down in history as one of the biggest American automotive blunders ever.

*Stitch* · 03-07-2010, 02:09 PM

Quote:

Originally Posted by turbo350

The diesel of this era has to go down in history as one of the biggest American automotive blunders ever.

the 350 diesel yes

the 6.2l diesel no

Drzronnie · 03-07-2010, 02:20 PM

I had a 6.2 and it was a piece of crap too. I will stick with my Mercedes diesel, cant beat a good old gas 350 for anything you need to do with a truck.

wfomkivdrvr · 03-07-2010, 09:08 PM

Quote:

Originally Posted by Drzronnie

I had a 6.2 and it was a piece of crap too. I will stick with my Mercedes diesel, cant beat a good old gas 350 for anything you need to do with a truck.

Oh well everyone has an opinion! my 6.2's are getting 19 and 25 mpg all day long i'd like too see your gas 350 deliver that kinda mpg and still tow a trailer running 35's and a lift.I DON'T THINK SO!

1973GMC_1500 · 03-07-2010, 11:29 PM

Quote:

Originally Posted by Russell

I've said it a million times before -- Despite some visual similarities, the 350 Olds is NOT a gasoline engine converted to diesel. You CAN NOT install gasoline heads on the diesel block, they are very different. That said, the 350 diesel does indeed deserve it's bad name, it is the 6.2L that does not deserve the 350's reputation.

If the engine is a gasser, then someone swapped in an Olds gasoline engine to replace it

Exactly. There WERE a lot of bad 5.7s. Once they switched to the DX block in '81, things got better. For the most part, they were ok. I would say there's a 99% chance the original engine in that '78 has been replaced with a DX block (goodwrech engine).

I sold my '81 C1500 with a 5.7 because I never had the money for a new injection pump. I wish I woulda kept it.

As long as you don't tow much or beat the s*** out of it, a 5.7 will be just fine.

I want a diesel car, Found an '81 Lesabre with a 5.7L diesel, I can buy it this spring when the ground dries up. I can already see dual exhaust with glasspacks in it's future

moneyeater · 03-07-2010, 03:25 PM

I had the 350 diesel in my ´81 and it used more oil then fuel and after changing all gaskets it took 2 weeks until they leaked again and the performance was more then poor!After 4 weeks it died and the dealer i bought it from gave a 6.2 l j code diesel to me!With that thing installed the truck was a real powerhouse and satisfied me until it crunched up the tranny,alternator,powersteeringpump and 3 starters!
After all that i converted to a 350 gasengine and wrenched 15 years to get it back on the streets!
I would stay away from a 350 diesel unless the rest of the truck is supernice and worth to keep it and convert to any other engine!
Volker

**truckfan** · 03-07-2010, 08:34 PM

i have a custom combiner buddy who has had one as a support vehicle for years. he has purchsed motors out of olds 98s and caddys a couple of times. its a cool old nostalgic ride. they are gutless, but i like them

*Stitch* · 03-07-2010, 11:55 PM

but does it get 19 mpg towing...don't think so...that's his point..

and that's alot of truck for a little 350 to be pulling around...let alone anything you put on the bed or hook to the back...I would hate to hear that thing going down the road loaded...ouch

**Corts60** · 03-08-2010, 12:26 AM

Hope you don't mind a 60-66 guy popping in, but my neighbor has a '78 Silverado with the 5.7L. He bought it brand new and told me within the first three years he owned it, he probably had the engine apart 5 different times. He installed ARP head studs and used a different thickness head gasket and washer set-up (I think) to bolt them down and he said ever since then all he needs to carry on a trip is an extra injection pump. He still runs it to this day getting 23 mpg.

And yes, you can't pull much and it is gutless. But to each his own.

I say go for it and put in the 6.2L!

*Stitch* · 03-08-2010, 12:30 AM

Quote:

Originally Posted by Corts60

I say go for it and put in the 6.2L!

this is also my vote

Drzronnie · 03-08-2010, 08:56 AM

Truck has sounded fine for the past 215,000 miles with a 800 gallohn sprayer on the back. a 350 is plenty, we keep our ups trucks tagged at 20,000lbs and they have a lil 4.3w motor in them. I did see a nasty 6.2 on here that was twin turboed, i forget where but I would like to find it again and see how much of that was one off fabbed. IF anybody in in the central PA area and wants a running 6.2, I have one and it is free to anybody that wants it before I scrap it. I know this isnt a sales thread but you guys would know if somebody wanted it. Hate to throw away a running engine if sombody can use it. And with the 19MPG no I cant get it towing butyou dont have a 27,000GVWR either and i got 20's LOL.

*Stitch* · 03-08-2010, 01:30 PM

I would take it...you wanna find out what shipping would be to a business address at 29150...if it's free, I could probably swing the shipping...and it'll be fine with the mods as long as you're giving it away...so put me first in line for it if you'll put it on a pallet and ship it...thanks

Chuck

Drzronnie · 03-08-2010, 08:38 PM

Quote:

Originally Posted by Fat Hoe

I would take it...you wanna find out what shipping would be to a business address at 29150...if it's free, I could probably swing the shipping...and it'll be fine with the mods as long as you're giving it away...so put me first in line for it if you'll put it on a pallet and ship it...thanks

Chuck

I will see what i can do.

turbo350 · 03-08-2010, 09:59 PM

Does anyone have an underhood pic they could post of a stock 5.7 diesel in a squarebody? I've heard much about them but never actually seen one.

03-06-2010, 04:30 PM	#1
dukes69 Junior Member Join Date: Jun 2007 Location: owatonna mn Posts: 133	is a 78 chevy with a diesel rare I am looking at a 78 silverado. The truck has had me confused for a couple days, as i could not figure out what motor is in it. I finally figure it out. it is a 350 diesel. my question is this a rare option? any help on this would be great. Dukes __________________ 1968 chevelle ss 396 4spd 1969 chevy 4wd 350 4spd 1970 chevy c10 long box 1970 GMC 4wd long box

03-06-2010, 05:58 PM	#2
Drzronnie Registered User Join Date: Feb 2010 Location: Lancaster PA Posts: 62	Re: is a 78 chevy with a diesel rare There are probably a bajillion people who will argue me on this but STAY AWAY. My first job was taking 350 diesels out of cars and putting gas motors in. They are horribly unreliable but I guess if you were just buying it for the novelty factor and didnt have to drive it you would be ok or if the truck is nice just put a 350 gas motor in. __________________ 82 C60 82 C20 (neverending project) 77 Mercedes 300D (gets me to work)

03-06-2010, 07:03 PM	#3
1976K5CHALET Senior Member Join Date: Jan 2003 Location: Grand Junction, Colorado Posts: 610	Re: is a 78 chevy with a diesel rare What he said...ditto! __________________ Doug Wright aka K5NUTT over @coloradok5.com Owner of http://groups.yahoo.com/group/ChevyK5BlazerChalets Certified K5 Nut

03-06-2010, 07:48 PM	#4
willett Another Day, Another Dollar Join Date: Nov 2008 Location: North Vancouver, BC Posts: 1,316	Re: is a 78 chevy with a diesel rare i dont think that the made the olds 350 deisel for very long for a reason... there was a big thread on here about them a month or so ago. check it out. __________________ -78 K20 Cheyenne 454 long box, 4" lift, 35" MT's, '84 cab, '80 box "its hip to be square"

03-06-2010, 08:15 PM	#5
dukes69 Junior Member Join Date: Jun 2007 Location: owatonna mn Posts: 133	Re: is a 78 chevy with a diesel rare i went and looked at it again and i think it was coverted over to gas, however it still has the diesel block. Am I going crazy? __________________ 1968 chevelle ss 396 4spd 1969 chevy 4wd 350 4spd 1970 chevy c10 long box 1970 GMC 4wd long box

03-06-2010, 08:18 PM	#6
willett Another Day, Another Dollar Join Date: Nov 2008 Location: North Vancouver, BC Posts: 1,316	Re: is a 78 chevy with a diesel rare same block as a gasser. don't quote me on this, but i think that its just a matter of switching out the intake, and ignition module i think that it will have a different cam though. __________________ -78 K20 Cheyenne 454 long box, 4" lift, 35" MT's, '84 cab, '80 box "its hip to be square"

03-06-2010, 08:51 PM	#8
Stitch Account Suspended Join Date: Jul 2008 Location: Where I come from, it's cornbread and chicken... Posts: 3,122	Re: is a 78 chevy with a diesel rare either way gas or diesel, if it's a 350 that was a diesel stay away...if it's a 6.2l then I say go for it, but it's not so stay away

03-07-2010, 03:16 AM	#9
jake wells Account Suspended Join Date: Sep 2009 Location: No Longer Here Posts: 352	Re: is a 78 chevy with a diesel rare ugh the 350 diesel was not a converted engine it has a thicker heavier block and the main reasons they failed back then was weak head bolts and poor fuel quality and how could it be so bad if its still running and not been swapped to a gasser

03-07-2010, 09:20 AM	#10
78-5.3 Registered User Join Date: Oct 2009 Location: Waterboro ,MAINE Posts: 547	Re: is a 78 chevy with a diesel rare my 78 was a 350 diesel WAS __________________ 78 C-10 5.3 LSX -4L60E

03-07-2010, 01:10 PM	#11
Russell Professional Grade Join Date: May 2003 Location: Fort McMurray, Alberta Posts: 7,915	Re: is a 78 chevy with a diesel rare I've said it a million times before -- Despite some visual similarities, the 350 Olds is NOT a gasoline engine converted to diesel. You CAN NOT install gasoline heads on the diesel block, they are very different. That said, the 350 diesel does indeed deserve it's bad name, it is the 6.2L that does not deserve the 350's reputation. If the engine is a gasser, then someone swapped in an Olds gasoline engine to replace it __________________ 1995 Chevrolet 2 Door Tahoe (6.6L LBZ Duramax / ZF6 / NP241 with 1 ton solid axle swap)

03-07-2010, 01:35 PM	#12
turbo350 Registered User Join Date: Aug 2005 Location: Twin Cities, MN Posts: 316	Re: is a 78 chevy with a diesel rare The diesel of this era has to go down in history as one of the biggest American automotive blunders ever.

03-07-2010, 02:20 PM	#14
Drzronnie Registered User Join Date: Feb 2010 Location: Lancaster PA Posts: 62	Re: is a 78 chevy with a diesel rare I had a 6.2 and it was a piece of crap too. I will stick with my Mercedes diesel, cant beat a good old gas 350 for anything you need to do with a truck. __________________ 82 C60 82 C20 (neverending project) 77 Mercedes 300D (gets me to work)

03-07-2010, 03:25 PM	#17
moneyeater Registered User Join Date: Feb 2003 Location: Northern Germany,near Bremen Posts: 684	Re: is a 78 chevy with a diesel rare I had the 350 diesel in my ´81 and it used more oil then fuel and after changing all gaskets it took 2 weeks until they leaked again and the performance was more then poor!After 4 weeks it died and the dealer i bought it from gave a 6.2 l j code diesel to me!With that thing installed the truck was a real powerhouse and satisfied me until it crunched up the tranny,alternator,powersteeringpump and 3 starters! After all that i converted to a 350 gasengine and wrenched 15 years to get it back on the streets! I would stay away from a 350 diesel unless the rest of the truck is supernice and worth to keep it and convert to any other engine! Volker __________________ My little US vehicle parts business: http://www.thegearheaddepot.com/ Come have a look! ´81 GMC C 10, Spanish Red

03-07-2010, 08:34 PM	#18
truckfan Senior Member Join Date: Apr 2009 Location: Lawrence KS Posts: 821	Re: is a 78 chevy with a diesel rare i have a custom combiner buddy who has had one as a support vehicle for years. he has purchsed motors out of olds 98s and caddys a couple of times. its a cool old nostalgic ride. they are gutless, but i like them __________________ 1981 Chevy C30 440 Holmes 42K one owner miles

03-07-2010, 11:55 PM	#19
Stitch Account Suspended Join Date: Jul 2008 Location: Where I come from, it's cornbread and chicken... Posts: 3,122	Re: is a 78 chevy with a diesel rare but does it get 19 mpg towing...don't think so...that's his point.. and that's alot of truck for a little 350 to be pulling around...let alone anything you put on the bed or hook to the back...I would hate to hear that thing going down the road loaded...ouch Last edited by Stitch; 03-07-2010 at 11:56 PM.



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03-08-2010, 12:26 AM	#20
Corts60 Just here to tinker Join Date: Jun 2008 Location: Holland, MI Posts: 3,697	Re: is a 78 chevy with a diesel rare Hope you don't mind a 60-66 guy popping in, but my neighbor has a '78 Silverado with the 5.7L. He bought it brand new and told me within the first three years he owned it, he probably had the engine apart 5 different times. He installed ARP head studs and used a different thickness head gasket and washer set-up (I think) to bolt them down and he said ever since then all he needs to carry on a trip is an extra injection pump. He still runs it to this day getting 23 mpg. And yes, you can't pull much and it is gutless. But to each his own. I say go for it and put in the 6.2L! __________________ 78 C10 SWB Diesel #1 (wrecked)http://67-72chevytrucks.com/vboard/s...1978+silverado 78 C10 SWB Diesel #2 (sold)http://67-72chevytrucks.com/vboard/s...d.php?t=650751 60 GMC Suburban (sold)http://67-72chevytrucks.com/vboard/s...d.php?t=445526 60 GMC 1000 (sold)http://67-72chevytrucks.com/vboard/showthread.php?t=298235 67 GMC 1500 (sold) http://67-72chevytrucks.com/vboard/s...d.php?t=803695 73 Chevy C20(Daily)http://67-72chevytrucks.com/vboard/s...d.php?t=852767 86 Suburban(summer unit) http://67-72chevytrucks.com/vboard/s...d.php?t=810697 88 Suburban 4x4(sold)

03-08-2010, 08:56 AM	#22
Drzronnie Registered User Join Date: Feb 2010 Location: Lancaster PA Posts: 62	Re: is a 78 chevy with a diesel rare Truck has sounded fine for the past 215,000 miles with a 800 gallohn sprayer on the back. a 350 is plenty, we keep our ups trucks tagged at 20,000lbs and they have a lil 4.3w motor in them. I did see a nasty 6.2 on here that was twin turboed, i forget where but I would like to find it again and see how much of that was one off fabbed. IF anybody in in the central PA area and wants a running 6.2, I have one and it is free to anybody that wants it before I scrap it. I know this isnt a sales thread but you guys would know if somebody wanted it. Hate to throw away a running engine if sombody can use it. And with the 19MPG no I cant get it towing butyou dont have a 27,000GVWR either and i got 20's LOL. __________________ 82 C60 82 C20 (neverending project) 77 Mercedes 300D (gets me to work)

03-08-2010, 01:30 PM	#23
Stitch Account Suspended Join Date: Jul 2008 Location: Where I come from, it's cornbread and chicken... Posts: 3,122	Re: is a 78 chevy with a diesel rare I would take it...you wanna find out what shipping would be to a business address at 29150...if it's free, I could probably swing the shipping...and it'll be fine with the mods as long as you're giving it away...so put me first in line for it if you'll put it on a pallet and ship it...thanks Chuck

03-08-2010, 09:59 PM	#25
turbo350 Registered User Join Date: Aug 2005 Location: Twin Cities, MN Posts: 316	Re: is a 78 chevy with a diesel rare Does anyone have an underhood pic they could post of a stock 5.7 diesel in a squarebody? I've heard much about them but never actually seen one.

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