Funeral notice. Dead 4.3! Going V8. What's next?

[sewlow]

So, last night the 4.3 in my truck pegged the thermostat. No water in the overflow tank. Hmmm. Where'd the H2o go? Nothing under the truck where I park it. So, I checked the oil. Uh oh. Chocolate milkshake brown. Just did an oil change last week. New oil does not look like this. Obviously, the intake manifold gaskets have gone south.
This engine has 335,000 kilometers on it. Better than 200,000 miles. Can't justify fixing it.
Now I'm looking for a V8. I would probably like to pull an engine out of a '96-'00 GMT400. Leaning towards a 5.7.
What do I need from the donor truck, other than the actual motor.
I've found a low mile '95 on C/L, but as these are OBDI, or OBDI.5, I don't think the electronic portion of that vehicle will be compatible.
My truck's a '98, with a 4L60e.
Please give a physical description of whatever I need. I understand old school points, condensers, & carburetors, so a lot of the electronic gizmo's are not within my experience.
Looks like the '97 is going back on the road for the winter, so I'm not in a real hurry, but, the sooner that I can start gathering parts & info. the better.
I kinda expected the 4.3 to head off to the great junkyard in the sky, just not now!
Can't say that I didn't get my $$$ out of it. She did treat me good, even though I didn't always do the same for her. Sigh.

Thanks to all future contributors in advance.
Now if you'll excuse me, I'd like to go spend some quiet time with her, & do some reminiscing about all the places we went & the good times we had together. I'll be making vroom-vroom noises as a final serenade.
4.3 R.I.P!

 

[nine4gmc]

i swapped my 93 4.3 for a 95 5.7, there was a few differences since 95 was the last of the tbi and the first of the pulse width modulated transmissions. seeing that yours is a 98, i would think any 96-99 5.7 swap would be quite simple.
Off top, you'd need the engine, engine harness and ecm. Your accessory bracket from the 4.3 should bolt onto the 5.7, just make sure the donor has everything in the same location as yours. You may need the transmission torque converter from the 5.7/4l60e for proper shift pressure. You will need the 5.7 starter and distributor.
if me, i would get the donor engine and go through it, replace all gaskets/seals and check/replace rod and main bearings as needed. new oil pump and timing set, tune up parts(ie plugs, cap, rotor, wires, filters and fluids).

 

[sewlow]

That was fast!
This will be a winter project, so I had figured on the re-gasketing & tune-up stuff. I will check all the bearings. If I can a fairly low mileage engine, I might not have to do bearings (fingers crossed!)
I am considering a cam change. Nothing too radical, as this is my DD six months of the year. But it is NOT babied. I drive the hides off this thing, sometimes! Well, O.K., a lot of the time. Suggestions?
Can't remember where I heard this, but someone once told me that the V6 torque converter has a higher stall, & that I should use it when I do the V8 swap. The tranny was recently rebuilt with a new T/C.

 

[TruckinAin4Sissies]

Vroom vroom. RIP

 

[sewlow]

Vroom vroom. RIP

In 2 part harmony. Thanks.

 

[Vigh_J]

NEVER ends

 

[SAATR]

Let's see... You'll need:

1. The engine (throttle body to oil pan, with electronics)
2. The mounts (I think the brackets are different between the 4.3 and 5.7)
3. The complete engine and transmission wiring harness
4. The ECM
5. The intake tube with MAF.
6. The 5.7 radiator, hoses, fan and fan shroud (not sure if the mounting brackets are different)
7. The 5.7 AC lines (dunno if the condenser and drier are different too).
8. The 5.7 throttle cable (I think they're shorter on the 4.3)
9. The 5.7 PS lines

The exhaust is obviously going to differ between the two, but I think you'll get something fabbed up. You may want to get the Y pipe just to make it easier. The ECM design changed between 97 and 98 too, and the pinouts are different, so you may want to get a harness and ECM from 98 and later.

Others will chime in if I missed anything, but good luck!

 

[nine4gmc]

well noted, i forgot the mounts, omg those were a total *****. you gotta remove the front coil springs to access the inner nuts on those and yes they are totally different. also, i used the radiator from the 5.7 because it had the transmission and engine oil cooler built in. the mounts were pre-tapped in my core support, i just moved the brackets over to accommodate.

the exhaust was the same from the 4.3 to the 5.7 on my 94. the 4.3 sits where the rear six cylinders sit from the 5.7 allowing it to bolt up no problem. my catalytic converter and oxygen sensor was in the same place too so i used the 4.3 setup since it was already there and all in good shape.

 

[Playare]

This is depressing because I don't think my 4.3's gonna run for too much longer.

Just curious, about how much do you think this is going to cost? and are you doing labor yourself?

 

[stroker52]

this is a good time to do a 6.0 swap just saying.. it will be the same $$$ and work, i can help you as much as i can..