4.3 Vortec

[MikeH]

14/15 with a 4.3?!?!?!? How on earth do you guys drive?!!?!?!?!?!?

I had a 95' lifted extended cab z71 on 33'' mud tires with the 5.7 and averaged 18/19!

And currently have a 88' S-10 with the 4.3 and auto and average 19/21!

I mean I drive smoother than most people but daym!

On the 4.3 very good very reliable motor, usually make it to around the 200-250k mark before any major problems (IF IT WAS TAKEN CARE OF!!!) Easy to work on, and the 700r4 they are usually mated to is just as reliable. Both are cheap to rebuild later down the road compared to many vehicles...About 800 for complete rebuild of engine and about 1200 on the trans...

But having a V-6 in a full size truck never made since to me...You have less power less towing and LESS GAS MILEAGE.....Why anyone would purposely do it is beyond me....

The V8s generally get better mileage in trucks than V6s because they don't have to work as hard to move the weight around. There is a whole forum dedicated to guys swapping in 5.7s in the S10 and their mileage always goes up substantially (s10v8.com).

And the model S10 also has an impact on mileage...if you have a base S10 yeah you should easily see 19 or 20. But if you have the 4WD or ZR2 package like I have, you have that same V6 moving around the weight of the transfer case/front driveshaft etc, skid plates, 2in lift and at least 31" A/T tires. The same engine is not as efficient under the additional weight, and the mileage suffers. I found the window sticker in my glovebox the other day and it was rated at 15/19 mpg (which we all know is an overestimate). I get about 15.x after doing a cat back, about 60/40 highway/city. I am also admittedly not the most patient driver.

Can't go wrong with the S10/Sonoma though. Parts are easy to find cause they share parts with the blazers and jimmys. You should enjoy it.

 

[jsquared]

I had a 2000 Blazer with the 4.3 V6, nice little motor with some getup and go. Ran well, OK mileage, never left me stranded. I had a 2WD auto and it ran great.

BUT, the coolant system can be a huge nightmare. Like BIG nightmare. Before you buy one make sure it is not warmed up yet and pull off the radiator cap, if it looks like this run (don't walk) away from the guy:

I had this happen to me and it SUCKED. Flushing the system monthly or no heater. Finally did the heater core and it stayed. New water pump twice, new radiator, new hoses, new thermostat (basically a brand new system front to back) and IT DID NOT GO AWAY.

Dexcool (the GM factory coolant) does not like regular green coolant, and when they are combined (say, during a "top off" while getting your oil changed by a high school kid at Jiffy Lube) the mixture can do bad things. GM still hasnt fessed up to this as far as I know, but most people think it is a combination of rust and gasket material that is being eated away by the coolant mix. Gasket material, you ask? Yep, and this is why the 4.3L V6's specifically have more issues with intake manifold gaskets (another thing to ask the seller about, it will burn coolant and throw a code if it happens).

Google search "dexcool mud" and decide for yourself. All I know is, it happened to me, it sucks, and it takes 30 seconds to make sure its not about to happen to you. My radiator and cap looked exactly like this. Choose wisely...

 

[AR556]

I had a GMC Sonoma in high school with the 4.3 and it held up fine. Kinda miss it, good low end torque for a small truck. The only thing I hated about mine was the color, 2tone white on gray.

 

[Tubbith]

Bought my 97 s-10 with the4.3 at 155k on the clock. I beat the hell out of it and never had any issues with it. Only reason I sold it was I couldn't afford the gas at $4/gallon.

 

[silverado31794]

Bought my 97 s-10 with the4.3 at 155k on the clock. I beat the hell out of it and never had any issues with it. Only reason I sold it was I couldn't afford the gas at $4/gallon.

So you started walking or rode a bike?

 

[Tubbith]

Nope. Tiny 4 cylinder into the truck, back into a tiny 4 cylinder. Going from almost 30 mpg to 16 or so will put a hurt in your budget when you are working part time and driving an hour both ways to school.

 

[cp1084]

I have a ext cab 92 S-10 with a 4.3, bought the truck from the original owner this spring and it has 50k miles on it...I average 20/21mpg every tank with the a/c on. This weekend I hauled my 4-wheeler in the back to durhamtown then to my girlfriends parents in Hampton and back home to Gainesville and got 23mpg. If you drive them reasonable they'll get good fuel mileage...The few friends I've had that has 4wd ones get 16 in town and 20 on the hwy. Should go 300k no problem...roller camshaft motor, i've seen many go 300k-500k with general maintenance done on them.

 

[sovietak474u]

I had a 2000 Blazer with the 4.3 V6, nice little motor with some getup and go. Ran well, OK mileage, never left me stranded. I had a 2WD auto and it ran great.

BUT, the coolant system can be a huge nightmare. Like BIG nightmare. Before you buy one make sure it is not warmed up yet and pull off the radiator cap, if it looks like this run (don't walk) away from the guy:

I had this happen to me and it SUCKED. Flushing the system monthly or no heater. Finally did the heater core and it stayed. New water pump twice, new radiator, new hoses, new thermostat (basically a brand new system front to back) and IT DID NOT GO AWAY.

Dexcool (the GM factory coolant) does not like regular green coolant, and when they are combined (say, during a "top off" while getting your oil changed by a high school kid at Jiffy Lube) the mixture can do bad things. GM still hasnt fessed up to this as far as I know, but most people think it is a combination of rust and gasket material that is being eated away by the coolant mix. Gasket material, you ask? Yep, and this is why the 4.3L V6's specifically have more issues with intake manifold gaskets (another thing to ask the seller about, it will burn coolant and throw a code if it happens).

Google search "dexcool mud" and decide for yourself. All I know is, it happened to me, it sucks, and it takes 30 seconds to make sure its not about to happen to you. My radiator and cap looked exactly like this. Choose wisely...

ALL quoted for truth. Had to change the gasket and all that crap on my girlfriends 00 chevy blazer. It runs great now. KILLS you on gas but we use it for its 4x4 use. Thats about it.

 

[silverado31794]

Locked the wrong thread other day thanks soviet for posting in it I think this is good info.

 

[300 wsm]

I have 2 of them a 97s-10 and 01 blazer and both have had the transmission replaced around 100.000 along with the entire cooling system. Fixing to put another trans in the blazer it has been a pain in my a$$ since i got it.So unless i could get one cheep i will never own another. I also have a 96 gmc sonoma 4 cyl 5 speed thats gets about 22 mpg and i have not had to touch other the the normal maintenance.