Saw a Chevy 1500 6.5L Turbo Diesel

[Nordby]

Had no idea they made these available in a 1/2 ton truck. Honest to gawd, made my friend lift the hood and show me.



It was a 2wd, single cab, with a topper. Nice clean, quiet truck. A 1996 I believe, plus or minus a year or two.



I know these diesel motors are grenades, but might it last in a half ton going up and down the road and not being used by a real truck?



Took a look at his emissions dyno - 151 rwhp and nearly 500 ft/lbs of torque (if I did the math right, I took the number and divided by his rear axle ratio). Nicely powered for a 1/2 ton truck I'd think.



later,

jon

 

[bmoeller]

They used the 6. 2's in them too. They put a 3/4 ton front end on them for the weight. Was told by a retired GM mechanic that the 6. 2 weighs twice what a 454 gasser does. They also put them in the half-ton 'Burbans.

 

[kevincook]

I had a friend with one, he like the one he had!



KC

 

[Rosco]

I have seen only one of these in my area and at first I though it was a conversion. What is even more rare is a 1990's 2 door blazer with the diesel (I am pretty sure they offered one).

 

[tgbol]

Rosco

The continued to use the 6. 2 in the Blazer, 1/2 ton Suburban and pick up until 90 It was dropped when they changed body styles.

 

[Evan A. Beck]

I've worked on countless 6. 5s, and the one in the 1500 is far different than the one in the 2500HD and up...



The one in the half ton is coded "L56" and is rated at 180 HP and 385 lb TQ. The heavy duty trucks use what is called an "L65," and is rated at up to 215 HP and 420 lb TQ. Not only is the programming in the L56 different, it uses an EGR system for emissions concerns (below 8500 GVWR has different requirements). I have seen so many of these engines fail because of the EGR. Here's why... The 6. 5 in all applications has the crankace vented into the intake system, right before the turbo. This is not a bad thing, until the EGR is introduced. Once you add some sooty exhaust to the intake air (which has oil vapor init), it creates a sticky tar-like buildup on every part of the intake system downstream of the EGR valve. It will accumulate on intake ports, valves, everything... It makes for a HUGE mess if you ever decide to clean it up.



The L65 engine is far better, especially when coupled to a five-speed. Power is pretty good and they are relatively quiet. They are by no means a turned-up Cummins, but they will hold their own. I've worked on a few G-series vans equipped with the L65 engine, and they flat out haul butt. I was really impressed when I drove one for the first time. I'd be willing to bet a fair amount of money it would outrun a stock PSD. No joke!



Anyways, back to the 1500 diesel...



GM sure did have an advantage when they were offering it. They were the ONLY ones selling a below 8500 GVWR pickup truck available with a diesel. For some, it was quite appealing. The 1500 Suburban and two-door Tahoe were also available with the L56; both of which are quite rare.



Don't badmouth the 6. 5 too much, it is a decent engine. Like anything, its got its problems... One thing is for sure though--they don't eat lift pumps like an ISB!!! Injection pumps are another story... *LOL*

 

[Evan A. Beck]

Almost forgot...



The 6. 2 was available through 1992, in the pickups. I have only seen one. They are VERY rare!

 

[Vaughn MacKenzie]

Evan, I may be picking up an '82 Blazer with the 6. 2L, I haven't seen the rig or what tonnage it is. I doubt there is a 3/4T Blazer. How rare would this diesel be? Does a '82 6. 2 have much potential? Do these have EGR, and if so, can it be blocked off? It has 170K on it and is hard to start but I know that may have more to do with the glow plug system than compression.



How have these engines done for cylinder wear and bottom end durability?



Vaughn

 

[dezeldog]

6.5 turbo

I would have to agree with Evan as I owned a 95 3/4 HD 5 speed I got real good service out of it and put a ton of miles on it with only one inj. pump. If GM would've offered the 6. 5 I might've bought another one but they came out with the jap POS so went to the CTD. 225k so far so good



Jim

 

[J DeMaio]

I've got a 1984 Blazer with the 6. 2 HD. It has no EGR valve and runs okay. There's quite a few of these old motors around these parts. It was a ex-military rig, all of these used the HD engines. Some were 3/4 ton rated but mine is only a half ton. There has been projects on these motors in four wheel drive magazines in the past, they were good, interesting articles. I like Chevy's as well as Cummins engines. The exciting part is that parts are plentiful; you can get parts easily at auto parts stores and almost everything interchanges between the gas and diessl rigs of this earlier year. I've heard people bad mouth em but they're going to be as good as you treat them. Take care of them they will last a long time.



Hope this helps!



John

 

[Nordby]

Thanks Evan!



That explains why his "Service Engine Soon" light goes on and off. Sounds difficult/impossible to keep the intake air clean, it would coat everything, make the exhaust dirtier, and be a downward cycle/spiral from there.



jon.

 

[Will24]

We have a 97 c1500 (2wd) long bed xcab sitting on the lot right now as a trade in. It is an l56 (non-turbo) automatic 5 lug Kind of an interesting combo...

 

[illflem]

The Air Force offered our research station eight camo '85, 6. 2 Blazers with M-16 racks for free just a couple of weeks ago. All were in running condition. No door locks, one key fits all. I declined.

 

[nickleinonen]

my tahoe is a k1500 chassis and it has the "S" [L56] 6. 5 TD engine. yeah the egr is crappy, but i "disabled" mine for "testing" purposes many moons ago. it is forsale right now... need to make room and $$$ for the cummins ram HD that i will get in 6 months [my new 1500 ram is sitting on the drive, while my 'hoe is on the front lawn ]

 

[TPCDrafting]

My dad has a '94 k1500 4x4 ext cab short bed with the 6. 5 and auto. It has the 2 big holes in the front bumper, this helps identify them. He has around 150k on it and has mostly used it as a commuter. He hasn't hauled much more than his golf clubs with it. He's burned up a few glow plugs, they seem to always rear their head when it gets cold. I know they aren't used much till it gets cold anyway. He also had problems with it shutting down when it got hot. Turned out to be an electronics module was overheating. It wasn't designed to get real hot, but they went ahead and mounted it right on top of the motor between the heads. He bought a replacement module and a relocation kit that put it in a front corner away from the motor. Other than that it runs real good. It will beat my '98 12 valve off the line, but it is an auto after all. (I'm working on this believe me ) I can kick his but on the hill and from 40 mph up I've got him by a bit. I compared it to my old Chevy k1500 4x4 when he bought it. It has added leaves in the rear and pulled wayyy better than my 350.

 

[bmoeller]

Where I used to work during the summer, I got to use a '92 K3500 truck with a 6. 5L and a 5spd. Used it to haul hay. Couple years later I heard it was for sale. Didn't have the money at the time. It was the only GM I would've bought. That thing had guts. My favorite part about it was the transmission. Had a granny gear and O/D. With the 4. 10's that was a perfect combination.



I've driven both the 6. 2 and 6. 5. I think the 6. 5 is a much better engine. Alot more power.

 

[Evan A. Beck]

Vaughn, the 6. 2 in the Blazer will most likely have the EGR motor... Kind of a bummer. It can be easily disabled, but there's not much point in that since the damage is already done. If you could find a Blazer with the J-series (HD) engine in it, then you'd be in much better shape.



Hard starting on a 6. 2 can be related to glow plugs, but it can also be a number of other things. The fuel supply system is marginal at best, especially if it still has the goofy fuel filter thingy mounted on the firewall. What a joke that thing is. I like to remove the whole thing and start over. Running a new line to a good Racor fuel filter is an excellent upgrade, and well worth the cost. With 170K on the one you are looking at, I'd find out what the history is on the injection pump and injectors... If it is the original pump, I would rip it off there right away. Reman pumps are cheap, around six bills. Always replace injectors at the same time you replace the pump. I'd also be leary of 170K on an EGR motor... Pull the air filter assembly off and look down in the intake. See of there's any buildup.



As for bottom end durability, they are pretty stout. Keep good oil in it, and do NOT let it get hot... Your bottom end will be toast. Definitely install an aftermarket oil pressure and water temperature gauge.



In LD trim, I think the 6. 2 is rated at 130 HP... Pretty dismal for a 379 ci engine, huh? *LOL* Actually, its a pretty strong 130 HP, and it can be turned up too. Just be SURE to have a pyro on that thing. It will get hot!!!



TPCdrafting: I see those little electronic modules go out all the time. It's just an injection driver module, and does like to fail when it gets hot. They usually last about 80K, and then the engine begins to stall intermittently, and then will eventually always stall once it gets warmed up. I've replaced countless modules on '94 & '95 6. 5s. It would be easy if they had located it somewhere other than on the side of the pump... Intake manifold has to come off so you can reach the lower bolt.



Bmoeller: The '92 was the first year of the 6. 5TD, and it was a very strong engine. '92 & '93 6. 5s were mechanically injected, and easy to turn the pump up on. With a 5-speed, a turned up pump, and no muffler, the mechanical 6. 5L will kick butt. It WILL give a B-series Cummins a run for its money.



BOMB ON

 

[nickleinonen]

the egr damage is reversable. if you disable the egr system, the intake will start to clean its self out slowly. my tahoe had the egr. the intake was coated with soot. i disabled it around the same time i put my gauges in [last winter around this time] now i removed them 2 days ago [selling it] and i took a peak down the hole i took boost from [the intake air temp sensor hole] and it looked pretty clean down there compared to how it was before. mind you, i do have a working crankcase breather system sending oil mist through the turbo to the oil will clean the soot off good [causes the problem, and fixes it with the egr gone]

 

[CJBoggs]

Vaughn,



I've got an 83 GMC Jimmy that is half ton and has the 6. 2L in it. Bought it at 130,000 in 93. Mine is a standard (non HD) engine and as such it does have EGR and believe me, the intake looked awful. I did replace the injection pump and injectors at 250,000 along with the transmission (700R4). I cleaned out the intake at that time and disabled EGR. The truck now has around 340,000 and that is the original engine. Of course most of the peripherals have been replaced a couple times, but the engine still cranks every time I turn the key. The longevity of the engine is both a blessing and a curse--it is great because it lasts, but it keeps going so I don't have a reason to get rid of it. It does make an awesome 4x4 for the winter when I don't want to risk the Cummins on all of our NC ice. The engine is starting to show signs of its age now though, as it doesn't pull the hills like it used to. Maybe a candidate for a Cummins transplant...



All in all, it's been a pretty good return on investment-$5000 in 1993. I do think that I am one of the luckier GM diesel owners though.



Evan,



You mentioned turning the pump up. Can you elaborate?? Thanks for the help.



Chris Boggs

 

[Evan A. Beck]

Chris,



To turn up the pump on a 6. 2L or mechanical 6. 5L, you have to take the top part of the pump off. Three 8mm bolts hold it on. After you removed the bolts, jiggle the top of the pump a bit, and it will pop right off. There are some linkages inside the lid, so be careful. Next thing you have to do, is rotate the engine by HAND until you see the main power screw become visible in the bottom of the pump... Its just beneath one of the linkages, and there is small oval window you will be able to see it through. Be sure to have a bright flashlight. It's hard to explain, but you'll see when you get in there. You'll need a 3/16" round-tip long allen wrench to adjust the fuel. Give it about one to two flats of the allen. Any more than that, and you'll have EGT problems.



Now comes the tricky part--putting the pump back together. You'll need to engergize the solenoids on the pump lid so they go back together correctly. If you don't get it lined up right, the governor can stick, and you will get an INSTANT 4,000 RPM when you try to start the engine. So be very careful!