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How is your 4.3L EcoTec3 V6 Engine working out for ya?

The4thgearkid
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Knightfall Enthusiast

Knightfall

Posted
Posted

Always been a fan of the 4.3 since we've had them in S-10 trucks and Blazers (I know the motors aren't similar but still). Now I just want to see a re-envisiominf of the Big-Block V6's from the old GMC trucks. Maybe turbo'd as a base model 3/4 ton motor....

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corwest
corwest

Couldn't be more true. Most people who speak poorly of things on forums go searching for a place to speak that way. It's very rare you find people who are completely satisfied who go looking for a pla

Brian S.
Brian S.

I had the 4.3l with 4wd/3.42 gears Xcab last year, now have the 5.3l with 4wd/3.42 gears Xcab and agree with what you say.   In normal driving, the 4.3 and 5.3 drive largely the same. The difference

KARNUT
KARNUT

Unlike getting the 6.2 you can get the 5.3 across the board with very little upgrade cost. Then you factor in the added HP can go up to 380 on e-85 it's a no brainier. I have nothing against V6s I hav

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cnrtool Enthusiast

cnrtool

Posted
Posted

I have 47,000 on my 2014. I am happy with it, and as a bonus I am getting a 18.9 average mpg since I bought it. Prior to that, I had a very fun to drive 2003 SS, but it couldn't pass a gas station without gulping 50 bucks worth.

BoomBoom19 Enthusiast

BoomBoom19

Posted
Posted

I own a 2014 with 22k miles. Honestly couldn't be happier. I had a 2013 prior to this with the v8 and I really cant tell much of a difference. I towed a uhaul (6x12) loaded up to the max from Wisconsin to New York and other than averaging 13-14 mpg, it handled the weight really well and had power to pass when needed. I went for the v6 because i rarely tow, and mainly like a truck because I could throw whatever I want in the back and I sit up above traffic. Plus I feel more safe. Didnt ever feel the need to have the v8 plus I got an amazing deal on my truck.

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  • 4 weeks later...
Baldy_81 New Member

Baldy_81

Posted
Posted

I drive a 2014 DC with the 4.3 and Z71 Package. Absolutely love the truck. I modified the Airriad MIT for the 5.3 to fit the 4.3 engine. Currently planning on doing a black bear tune as well. I don't really tow anything, but i have had 1200 lbs of Concrete in the back a few months back, and truck drove like there was nothing there. I would recommend this engine to anyone.

 

 

Just curious how much modification was required for the MIT to fit and wether it made a difference or not.

obrien19 Enthusiast

obrien19

Posted
Posted

Not much modification. Just need a 4 inch to 3 inch coupler for the throttle body and a half inch PVC plug. Hard to say how much of a difference it made. I feel like it did, but others on here would argue that it won't make a difference

 

 

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  • 1 month later...
Tw1tch New Member

Tw1tch

Posted
Posted

Other than the trans fluid temp running higher than I'm comfortable with, my 2015 4.3L is doing fine. Little over 3000 miles. I'm going to add a Tru Cool Mini Max trans cooler to it very soon & be done with the high fluid temps.

 

 

How did that TruCool work for you? Mine still hasn't jumped over 195F, but to be honest I'm a little sketched out by such a high reading on the highway.

Imcrazy Senior Enthusiast

Imcrazy

Posted
Posted

I used to have the 4.3 ECO TEC, with 13k miles on my new 5.3 ECO TEC, I'd pay the $800 all day long to get the bigger motor. The 4.3 does the job but, it's nice to have that little extra in the V8. FWIW I had the 4.3 truck for about 30k miles and only a few times did I want more power, mostly on the highway, both trucks are 4x4 3.42 rear end double cabs. If you find a screaming deal on 4.3 don't hesitate they're good motors and I would buy a truck with one again IF it was about 2k less than a comparable 5.3L truck but, new, your talking less than 1000. Also I get the same MPG with this truck as I did the V6. 19 mpg without a trailer hooked up.

11bDad Enthusiast

11bDad

Posted
Posted

 

 

How did that TruCool work for you? Mine still hasn't jumped over 195F, but to be honest I'm a little sketched out by such a high reading on the highway.

Installed it in Dec, but it didn't do much because of the Thermal Bypass Valve they have used since 2014. Install was fairly easy and I was real pleased with the way it turned out. I modified the valve (easy & free), and it really cooled it down. I can run the interstate in 95 degree SC weather at 145 degrees, or sit in heavy traffic at 175. I used the Tru Cool Mini Max 20k btu cooler. Well made. Torque converter and pump went out at 10k miles, so after dealing with that ordeal I feel better about the tranny running cooler. Cooler%202_zpsu08mwo4s.jpg

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Baldy_81 New Member

Baldy_81

Posted
Posted

I have nearly 80000 kms on my 4.3 and so far my only complaint was towing a 4000 lbs camper with some stuff in the back of the truck. The issue was not being able to keep it in 6th gear so I had to run at 105 km/h @ 2800 rpm in 5th. Would like to know how the 5.3 would fare with that extra HP. Other than its been good.

newdude Senior Enthusiast

newdude

Posted
Posted

I've driven one for 300 miles (double cab 4x4) so no ownership experience...but I do have a relevant question for you 4.3 owners. Anyone run the Range AFM delete on theirs? Interested to see some mileage differences between leaving it active and disabled.

 

 

I have nearly 80000 kms on my 4.3 and so far my only complaint was towing a 4000 lbs camper with some stuff in the back of the truck. The issue was not being able to keep it in 6th gear so I had to run at 105 km/h @ 2800 rpm in 5th. Would like to know how the 5.3 would fare with that extra HP. Other than its been good.

 

5.3 would run in 5th with tow/haul on with that load.

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  • 3 weeks later...
NYSierra4 Enthusiast

NYSierra4

Posted
Posted

Has anyone done anything with the exhaust? I know most 5.3 owners just say to get a 5.3 but I'd like a little more throat when I hit it on the highway. Thx

 

 

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tmo Enthusiast

tmo

Posted
Posted

I wanna know how everyone is getting 20+ mpg with their trucks. I have the 4.3 and the closest I've ever gotten to that is 18 when babying it. Normally I get around 15-16 highway.

 

 

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NYSierra4 Enthusiast

NYSierra4

Posted
Posted (edited)

I wanna know how everyone is getting 20+ mpg with their trucks. I have the 4.3 and the closest I've ever gotten to that is 18 when babying it. Normally I get around 15-16 highway.

 

 

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So there is a big difference between what the computer tells you and what your actual mpg is. I was averaging around 20-22 with a max of 25 b4 my lift and tires but when I plugged the numbers into a mpg app it was more like 18. After my lift and tires I'm getting around 14-16.

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Edited by NYSierra4
azsundevil Enthusiast

azsundevil

Posted
Posted

I wanna know how everyone is getting 20+ mpg with their trucks. I have the 4.3 and the closest I've ever gotten to that is 18 when babying it. Normally I get around 15-16 highway.

 

 

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Yep, that's spot-on for me with my 4.3L. I think a lot of people who brag about high MPG are being a little dishonest with themselves and maybe not telling the whole story. When I calculate my MPG by hand, I usually get around 18 if I've been driving economically, and I've seen as low as 14-15 if I've been driving REALLY aggressively (I live in Socal, our freeways are a free-for-all deathmatch).

So there is a big difference between what the computer tells you and what your actual mpg is. I was averaging around 20-22 with a max of 25 b4 my lift and tires but when I plugged the numbers into a mpg app it was more like 18. After my lift and tires I'm getting around 14-16.

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Yeah same here, the computer is waaay off on mine. And I'm running stock tires with no lift. Computer is off by as much as 3-4 mpg sometimes.

GMC2015 Enthusiast

GMC2015

Posted
Posted

I wanna know how everyone is getting 20+ mpg with their trucks. I have the 4.3 and the closest I've ever gotten to that is 18 when babying it. Normally I get around 15-16 highway.

 

 

Sent from my iPhone using Tapatalk

 

It boils down to how you drive and what type of truck you drive. Heavier tires and a level will decrease you mileage quite a bit when you have a v6. What did you average when the truck was stock?

 

This is what I've averaged so far with mine. 70% highway driving and 30% stop and go city driving. Also mixed with some spirited driving (Single cab, 2WD, 3.23s, bone stock)

 

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