What is your opinion on the chevy 6.2L diesel

[Tractor-man 111]

Just bought a 1982 chevy Scottsdale C20 with the 6.2L in it. I am the 3rd owner and the truck has original 70,000 miles and is in very good condition just curious of opinions on this rig. I paid $7,000 runs and drives great.

[arcticbuicks]

Nice truck, I had 6 or 7 -6.2 gm diesels for snow clearing business and a driver in a suburban 4x4, one truck we had was ex military and was 24 volts and the better engine code ,been quite a few years, great on fuel , not a lot of power for towing , I found them a lot less problems than the 6.5 of later, there is a better 6.2 if your lucky you have one , it was J code from memory and mostly in military or heavier trucks .the only problems I had was glow  plugs , fuel shut off switch and odd injector pump , but they are cheap , I think they got a bad reputation by guys that tried to tow too much with them, easy to work on yourself engine and almost no electronics …….I would love to have another one 

[Swear57]

We worked on more 6.2 then I care to remember even the 5.7 in the cars. The 6.2 we had problems with the glow plugs, injectors, injector pump, fuel heater, fuel shut off switch, & head gaskets. The automatic was terrible for towing. Great truck for running around for small loads. The manuals you could tow with.

[Bryan G]

The first year they were available in a full-size van, '82 I think, a friend bought one. At about 190k he didn't need it anymore and sold it to me. His was the first GM truck I'd seen from that era that had never had the 700R4 rebuilt. I think he'd replaced the pump at some point. Some EGR lines had rotted and were n/a so he rigged them up with PVC and straight hose. When I got it the engine had what felt like a miss. It turned out to be a clogged rear fuel filter. It hadn't been many miles since he'd changed it, but the rig had been sitting a lot. 

 

No power to speak of, and a challenge when I took it through the mountains, but around home not so bad. When warmed up, the quickest starting engine I've ever owned. Same mpg no matter how I drove it or how it was loaded. I got a steady 20 which I thought was great for that big, heavy brick. He claimed he used to get 26 which seems amazing. 

 

I was sorry to see it go, and still miss it, though less so since diesel prices are what they are. I always thought of buying a Detroit Diesel nameplate and putting it on the back; not 100% correct as I think technically Chevrolet Motor built these, but Detroit had a big hand in their design (vs the Olds 350.) 

[Frank DuVal]

You could use a brick as the cruise control, and that was back with the national 55 limit.

 

I should throw stones, I own two of the 350 diesels..... and like them.

[Tractor-man 111]

Lol the cruise control douse need fixed and I am at a Home Depot.

[JFranklin]

My truck with that engine was a hard worker, but was very low geared. Glo-plugs didn't help a lukewarm engine so we sometimes had to wait for a cool-down before restart.

Edited February 12, 2023 by JFranklin (see edit history)

[intimeold]

I worked on a lot of the 6.2's.

 

The main thing that we saw; were glow plug problems.  But most of that was probably, operator error.  There was a set procedure to start these trucks, when cold and they didn't like it if that procedure wasn't followed.  I suppose, if the trucks lived in warmer climates, the glow plugs may not have been a problem. 

 

The trucks were slow; compared to modern diesels.  But really none of the problems newer diesels have.  These were before the Government, tried to choke the life out of the engines. no DEF needed to run these. 

[Tractor-man 111]

So I’m curious I didn’t know there was a procedure that these trucks liked when starting cold. What is the procedure?

[Bryan G]

1 hour ago, Tractor-man 111 said:

So I’m curious I didn’t know there was a procedure that these trucks liked when starting cold. What is the procedure?

Check the backside of the driver's side sun visor. It details it well. When I followed that, it would start dependably. In cold weather I'd plug in the block heater the night before and that was a real help. Even with that, on a cold morning it would fog up the whole neighborhood with smoke!

 

For the cruise control, on mine I just found it needed adjusting. There were, I think, 2 places in the linkage where you could tighten it up. Mine just had a lot of slack in it. After that it worked really well.

[gossp]

I am a fairly active reader on suburban and square body forums, although I don’t have a square burb anymore (for now).
 

The 6.2 has a strong following. The lack of towing power reputation is present, but I don’t think it is a function of not having enough power as much as not having the power where you wish you had it. A manual trans helps there. 

 

I have seen 6.2 trucks for sale with over 300k miles and have seen plenty of claims of over 20mpg, making them something I wouldn’t mind owning some day but am not actively chasing, yet. 
 

you can tuck a lot of fuel storage under those trucks (both sides and center tanks: over 100 gallon) making a 6.2 popular with the over-land (not Overland) and prepping crowd. A part of this following may have to do with the existence of factory 6.2 4x4’s where 454 gas 4x4’s were not made, at least in the suburbans I follow. 
 

as for the rig in question, it will likely still be a running workhorse serving you well many years after an off the lot $30k used pickup has returned to the earth. 

[chistech]

I’ve had many 6.2’s and still have this 83 M1009 military blazer. It came out of Alaska with 26K on the odometer. No top as it had a special body mounted at one time and it had the large heater exhaust hole in the fender along with the two insulated battery boxes. It was called the Artic Heater package by the military. It was delivered to a local town government that flooded it with orange paint (it can be seen in the restoration picture) to the point it was down the defrost vents and into the heater box. I bought it from a guy who got it from the town’s auction and he kept the motor, transmission, and transfer case for his other plow truck. I did a frame off/rotisserie restoration and civilianized it with AC, power windows, locks, rear glass, full instrumentation, radio, fat mat insulation, leather power front Yukon buckets with heat added, and even heated mirrors. I installed a rebuilt 90 J code engine, a built 700R with HD diesel torque converter, a 208 NP transfer case, and left the stock Gov lock rear. Because I added 33” tall tires versus the original 31’s is the reason I went with the 700R over the TH400 3spd is the 700R has a lower 1st gear. The performance is very good to excellent for a driver truck. I do tow a small single axle enclosed trailer with RC planes in it but wouldn’t try more. It cruises all day at 72-75mph and gives me right around 25 mph highway. It’s got massive braking power because of the hydra-boost braking system plus turns on a dime. My restored hardtop hangs in the rafters of my garage because my wife loves convertibles and she loves driving this truck, especially to the beach. I can’t tell you how many times I’ve been asked if I’d sell it ad just last week was offered $20K which I turned down. This truck is promised to my son. It just turned 36k .

      Here’s my 62 advice. Your 82 is a red painted 6.2 and we’re known for a few early 6.2 kinks. One was head gaskets which the issue went away around 84-85. Your temperature sender  is a round tube type one in the back of the passenger head (if I remember right) and the are known to fail which an overheat goes to head gasket failure. Adding an aftermarket sender and temp gauge is not the worst thing you could do. The factory fuel filter base is known to develop air leaks which will cause hard starting. Often people are told their injection pumps are ad when in fact it’s your filter base. The 6.2 lift pump is just like a pump on a gas engine, is mounted on the lower front passenger side of the engine and is cam driver. Check for fuel line leaks from the pump to the filter. Order a set of John Kennedy hot glow plugs for your truck. They don’t swell at tip like a Delco  can. A swollen glow plug can give a hard time coming out and sometimes the tip breaks off in the pre chamber area! Not good! The 82-84 glow plug module from what I understand could be problematic also so research that. I added a push button to activate the glow module because, as someone mentioned, sometimes you motor is in a lukewarm state where the module won’t activate the glow plugs but the motor isn’t hot enough to help ignite the diesel even with good compression. The 62 has pre-chambered heads and not direct injection so that is why some glow plug with the lukewarm motor is helpful. If you have good fuel with no air leaks, and good compression your 6.2 will run and run good. In most cases when a 6.2 doesn’t want to start or run its because of a fuel leak that either lets air in or the fuel to run  back from injection pump causing an air pocket. Learn how to change you filter. You pull the heavy red wire off the top of the injection pump remove/install a new filter, then open the little T valve. Then turn the motor over until the fuel comes out the small hose connected to that T valve. Close the valve and reattach the red wire to the top of the pump. And one last thing. Always check your starter bolts and battery cables. The starters like to come loose and starter cables on these old trucks usually have some green corrosion getting into the strands causing issues. You have a nice truck there, enjoy it.

[Frank DuVal]

On 2/13/2023 at 7:39 AM, gossp said:

likely still be a running workhorse serving you well many years after an off the lot $30k used pickup has returned to the earth.

Is that because they leak enough oil to rustproof the undercarriage?🤣

[jp1gt]

I like old cars but for me trucks are as good as they can perform a function. My first hauler was a 72 powerwagon with a 390 HP 440 pursuit eng. then a 7.3 Ford with a manual trans. Now I have a 2011 Chev with the duramax diesel. I have towed 20K pounds with it with no problems. Seems they keep making them better.

[PWN]

Great looking truck! I prefer Doge generation one Cummins diesels....the best trucks ever. Especially my 92 LE 4x4. LOL

 

Biodiesel! No reason not to make some with waste veggie oil. Or a heated veggie tank!

 

 

[chistech]

Took mine for a nice ride yesterday and another thing came to mind. 6.2’s like to be fed fuel, but not force fed. When accelerating, gradually press the pedal and you will know what speed to push the pedal if you listen and feel the engines response. Flooring the pedal does not work on a pre chamber diesel like it does with a direct injection one of modern design and lots of raw fuel in the 6.2 is harder for it to ignite and make power. Same goes for passing someone on the road. Plan your pass earlier than a gas car and start feeding in the fuel as the RPMs come up much slower so does your speed. Where our 6.2’s have a big following is the rock climbing guys who love them. Lots of bottom end torque, the ability to move in idle without stalling, and the ability for the motor to be at virtually any angle and keep running. Carburetor gas engines are susceptible to severe angles because of the floats. Even gas fuel injection does have the torque the 6.2 does.