Vortec 4.3L V-6 -- Opinions Wanted.

Don't know for sure about the USA - but from what I hear Canada basically copied your laws (your EPA carries a BIG stick) - Up here it is illegal to top up a system without doing a thorough leak test (with the system evacuated) and finding the system "tight". - which means it is illegal to "top up" the system. You draw the system down and do a vacuum integrity test. If there is no vacuum leak, or the test is inconclusive, you charge it with nitrogen and do a "bubble test" of all connections and any place that is suspect. If no problem is found, you recharge the system, installing a leak detector dye. MOST shops now also add a "sealer-conditioner" to condition the "O" rings and seals and help prevent future leaks (and mabee fix minor leaks that could not be found) You are also required to document how much freon you take out and how much you install in every system - which means you need a recovery unit.

Like I said before - for a DIYer it only hurts when you get caught - but like I also said - your EPA carries a BIG stick.

my 1991 s10 with a 4.3 vortec has a lot of power only problem I have when i t cold it hard to start and it smoke wen I first crank it up in the morning iam getting ready to replace my 4.3 with a 6.0 liter engine I have a 700 r transmission behide my 4.3 all have to do is switch motors and wire harnes s

I've had two 1998 Blazer with 4.3, and they have worked well for me. I bought both of them about

They are "rough as a cob" as our Limey friends would say. My dad had one in a full sized van. It al;ways sounded like it was revving it's guts out (and it likely was - the old man had a HEAVY foot!!) It worked well for him as a working truck untill he retired from working as an electrician - and it served him as a travelling van for several years after that, crossing the country several times. He sold it to a guy who crossed the continent a few more times before having it squashed between 2 transport trucks - and walking away from it. It was never a particularly GOOD truck, but it was better than his previous '69 GMC pickup by a wide margin, and it never gave any serious problems. It was always a bit gutless, always a bit noisy, drank gas like there was no tomorrow (as much as a 305 V8, anyway), but NEVER let him down.. Personally, I've only owned 5 GMs. A '28, a '35,a ' '57 , a '67and a '95 Trans Sport. Only owned the '57 for a couple of weeks. Never drove the '35 in the 4 years I owned it, and I only owned the '67 Nova for 3 weeks. The TransSport got me sworn off GMs for good. None of them was a significant improvement over the '28, mechanically!!

Hmmm this is interesting. My father bought a 2000 s10 with the 4.3 from som eone @ 90,000 miles. I'm guessing a case like yours was just bad luck. I co uld be wrong though. We haven't had any problems with the engine itself- mo re so from poor quality parts on the truck breaking from wear and tear. My only complaint is that rarely I've notice some hesitation in low RPMs. Howe ver this went away after changing spark plugs and some fuel injector cleane r. I think the iridium spark plugs may be too harsh for the engine. I read on another forum that a guy install platinum plugs and he got a smoother re sponse and the plugs didn't char up as quickly. Thats all i got. been driv ing the truck about 40,000 miles now.

No such thing as theindium plugs being "too harsh" Either they are the right heat range or they are not - but I had very poor results with indium plugs in my PT cruiser. Certain platinums are just plain trouble too - like Bosch . On a GM I'd run A/C Delco plugs - and nothing else. If AC makes a dual plat for the application, I'd ude them. The 4.3 is not a bad engine. It's "low tech" and robust. Not a performance or economy engine.

the 4.3 from someone @ 90,000 miles. I'm guessing a case like yours was just bad luck. I could be wrong though. We haven't had any problems with the engine itself- more so from poor quality parts on the truck breaking from wear and tear. My only complaint is that rarely I've notice some hesitation in low RPMs. However this went away after changing spark plugs and some fuel injector cleaner. I think the iridium spark plugs may be too harsh for the engine. I read on another forum that a guy install platinum plugs and he got a smoother response and the plugs didn't char up as quickly. Thats all i got. been driving the truck about 40,000 miles now.

I've got a 98 Blazer with a 4.3, and it's got low speed power problems. I got a fuel filter, but the mechanic put it up in the air and there was a pretty new one there. I'll try some fuel cleaner.

Advance Auto Parts alternator "Drive Works" has failed several times, each less than a year. Last time about two months. Free replacement, I'm on number five (5) alternator.

Your reply made me spew my coffee all over my screen...Ah, nothing like a good morning chuckle! Cheers and thanks for the memories!

I've had around 10 different 4.3 powered vehicles. Haven't had one that didn't make it well past 150K still going strong. The chassis were usually well rotted by the time I replaced the vehicle. I did sell one still road worthy, it's still on the road at 250K My current 02 has 191K on it. Still runs great. Has an emissions issue with the EVAP but not engine related.

FYI the 4.3 is a 5.7 with 2 cylinders missing.

Lost my last 98 Blazer to a traffic wreck about 260k, and driving another one, at 253 or so K. A bit sluggish in the morning, I suspect it needs sparks and some fuel injector cleaner.

My Tradesman work van is powered by a 4.3 with two cylinders added.

. Christopher A. Young Learn about Jesus

including the people.

some quoted text

Well not all Chevy 4.3 vortec engines were junk. I bought my 1994 1500 manu al transmission and 21 years later with 245,000 miles it runs better than n ew. All original parts still in. Maintenance is key. Many people wanted to buy it but it's to good of an old Chevy thruk.

I'm on my second Vortec, and has worked well, for me. First one I bought about 105K miles, went to about and sold it about 260K.

Did have to replace the alternator several times, and the ignition coils and modules were known to go out.

Only a couple miles into the second one, but it runs nicely. Starts well. Works on 87 Gasohol.

I have hadmy 4.3 c1500 since 96 with 302,201 miles still no problems and no oil consumption and runs like new

Yes I too am disappointed with my 4.3L moter it only has 315,000 miles on i t and now I have to do a tune up I mean its only going on 22years old the d ealer lied to me when I bought this thing he said it would probly outlive m e and that was a lie because if I don't do this tune up it might not run up to par and I may very well out live the vehicle so I just don't know I was wanting a good 50 years out of this thing so I am upset.

I have a 1993 GMC Sierra c1500 with the 4.3 liter V6 2wd and it has 340,000 miles on the motor. It was my dad's truck, but when he passed in 2011 I ke pt it up over the years and still have it today. This truck doesn't have th e power like my 2000 GMC Sierra c1500 2wd with a 5.3 liter V8, but still in all over the years it's been quite a reliable truck. My friends named it a s "Old Faithful" dry as a bone without any leaks and doesn't burn oil. I've had to change a few things over the years to keep it going, but nothing to o major and the motor is still going strong.

My dad bought a G20 van years back that the salesman said had a 350 in it. Dad said it was a bit lame for a 350 I took one look and laughed a bit. It was a 4.3 six-pot. Burned a lot more gas than his old 230cu inch HandiVan and had quite a bit more power being almost 40 inches bigger and fuel injected.. Like the 5.7 it was derived from it was pretty much trouble free - not unlike my 4.0 Ranger.

I know this post is old, but I just came across this post and since I have a 2004 Oldsmobile Bravada with the 4.3 V6 Vortec engine, I thought I would reply. My Bravada has 114,000 miles on it and have never had trouble like you have experienced. My engine runs smoothly whether it's a cold morning start or after it has warmed up. I have no shake, no shudder, nothing. I have done m aintenance on it. I have had the differential fluid changed, the transfer c ase fluid changed, engine oil and filter changed, new spark plugs, new igni tion wires, had the cooling system flushed with a new thermostat. I had all this done not because I was having any trouble, just to prevent any troubl e from occurring. Everything works like it should. I have no lights lit on my dash, I have plenty of power and shifts smoothly. I don't know why you h ave had the trouble you had but honestly, I have had no problems with my en gine.