Hey guys !

Got my first Chevy truck the other day for a project. Got it on the cheap so I am not unhappy about anything at this point. (1992 1500 5.7L 2WD Auto, Single Cab, Long Bed, Lifted 4") I paid $600 for it, with motor condition unknown. After tearing down the motor to inspect and then rebuild, found a grand canyon sized crack in the intake valley. I am dropping another (running) 350 into it next weekend to get it out on the road, but my eventual plan is this:

I plan on painting woodland camo, adding a old school military style brush guard (I am a old desert storm vet, so old school is what I like), wooden stake side bed rails, Bumper Shackles, etc. to do a old school late 80's field truck.

None of that is a problem, but here is the rub. If I am doing a mil truck, I want to pop in a 6.2L diesel, nothing sounds better to me than the clatter of a diesel motor. It should have (I am going to crawl under and verify tonight) a 3L80 transmission on it. Little background information, I drive like a 90 year old man, I have a very light foot. Speed and power hardly if ever pop up on my radar. I see no point for myself to spend $ to chase HP. With the 350, I have a HEI electronic distributer, so no computer control, just one power wire. The throttle body removed, and an adapter plate for the carburator. Have an aluminum plate mounted in the dash with all aftermarket gauges (Temp, Oil, Voltage, Speedo, etc.). I hate dealing with vehicle computers and would rather spend some money to build seperate controls and gauges, so I know the vehicle inside and out. Nothing I hate worse that then knowledge of having one small box that controls everything without the ability to work on it. If anything goes wrong you have to replace it.

(multiple sensors and plugs)---wires----(magical electronic box)----wires----(bunches of blinky lights)

I learned to work on a 66 mustang, so the closest thing to a computer in it was the calculator I had in my backpack to go to school. So my questions are as follows:

1. Will that 6.2L diesel bolt to the 3L80 transmission, or will I have to get a new bell housing?

2. Does the engine need to "talk" to the transmission, or being that old is everything more mechanical?

3. Being that it will be an 80's style diesel, it should be a mechanical injectors so there will be no computer to fool with?

4. Will I need a new radiator, or will the exisiting suffice?

5. What on that diesel would need to be wired? As of now, there are only (4) wires to the 350 (Alternator, Temp Gauge, Oil Gauge, Ignition Wire)



Thank you in advance for all your help!
Rob

 

I can't help with your first two questions. But,

#3- All the early 6.2 motors were all mechanical, no computers. If you are looking for a used 6.2 you might consider military take out motor. The mil take outs will be 24V so the injection pump will need to be changed for a 12V IP. The starter will also be 24V and need to be changed to 12V. Get the newer style starter for a 6.5 as they are gear reduction and much lighter that the original direct drive starters. The brakes on your 92 pickup are most likely vacuum assist, and since diesels don't have any vacuum the vacuum brakes will need to be changed to a hydroboost brake system. I have an 1983 K1500 with 6.2 and 1994 K2500 with 6.5 and both have hydroboost brakes. The 6.2 motor does have a vacuum pump in the same location as a gasser distributor, but I don't think it is strong enough to operate the vacuum brake booster. It will work the vacuum heater controls though.

#4- You will most definitely need a diesel radiator. The 6.2 and 6.5 have indirect injection which tends to hold more heat in the heads. Both 6.2 and 6.5 need more, and better, cooling than the gasser does. The radiator core support on my 94 has a bigger opening than the gasser core support does. If my memory is correct it seems like the core support for the gasser can be opened up to work for a diesel radiator. You may need to compare to a diesel core support to see what you will need to modify to make the gasser support work for a diesel.

#5- The alternator and gauges should be similar gasser to diesel. I do recommend the CS144 alternator though. My 94 had the CS130 and I was not satisfied with the lower speed output. The CS144 has much better lower speed output. I don't know what alternator you currently have, but when I switched from the CS130 to the CS144 on my 94 I found an alt (97 Suburban I think) that was a plug and play as far as the electrical connections. I did have to rework the mounting as the CS144 is physically larger than the CS130. The ignion wire should work to operate the shut-off solenoid on the 6.2 mechanical IP.

If you have any more questions I will try to answer them. Also, check with GM diesel forums and their members. One that I frequent at times is thetruckstop.us which happens to have some very knowledgeable members. I'm not on this site every day, but I do try to check in here a few days a week.

Don

 

The 3L80 is was a revised name for the TH400 trans. The last year for it was '90. By '92 the only autos available had overdrive and lockup... the 4L80E and TH700. A K1500 with a 350 will have the TH700. It will physically bolt up to the 6.2/6.5 diesel. It may need some different components to become diesel friendly i.e. torque convertor.

IMO, stay away from the electronic injection pumps... too many headaches. There are some mechanical 6.5's out there (93 trucks, 93-95 vans), or you can put the old style injection pump on the newer engine.