5.7 350 to V6 (4. something)

[broncoman94706]

I have a 97 Silverado and it has a 5.7 350 vortec. I dont use it to tow or haul. I just like my truck. I know the OBS came with a v6. Has anyone ever gone to a v6 from a v8? Some might say just to buy another truck but mine on has 68k on it and I was thinking I could sell the V8 to some one who needs a replacement and buy myself a crate v6. Seems like everyone is upgrading. I also was wondering if I would get lousy MPGs with a V6 because it would be working to had to move my c1500 ext cab. What you guys think?

[JollyBowtie]

You are gonna have all the same issues of swapping v6 to v8, just backwards. Going to a v6 computer and wiring harness. The v6 trucks use a different fan shroud. You could always go electric fans, that would help with the underpowered state of the V6. In a single cab pickup the V6 really isn't a bad motor, but the added weight of the extended cab can really take a toll on it. If you could find someone that wanted to swap to a V8, that would work best for you, you could trade everything you need.

ROb

[Outlawz2004]

I wouldnt. I would spend a couple hundred bucks and get a custom tune to optimize your current engine, thus getting better fuel economy and have power when you need it. best mpg I could get out of my 97 reg cab 5 speed v6 was 23 with intake and exhaust done, an ext cab with a 350 can get 20. A reg cab 350 driven right should have no problems pulling down similar mpg while still having the extra available power if you ever need it.

[Srabai47]

i cant imagine a good reason to swap to a 4.3.

[Jmac72]

i cant imagine a good reason to swap to a 4.3.

Me either.Less power,worse economy.And all the work to get those results.
You could not get enough cash out of your engine to buy a new crate v6 either.

So It would cost you a good chunk of cash,and a bunch of work.To get less performance all around.On a good low mileage truck.That will now be worth less when you decide to trade.
Did I miss anything.

[TheBigMortboski]

Your rate of return wouldn't be feasible. The 4.3L V6 isn't exactly a Prius, although it will get slightly better mileage than the 350.

If it were me, I'd wait until you'd usually replace your vehicle and buy something with better economy. If you need a truck, get a Toyota Tacoma or Nissan Frontier. If you don't, there are a lot of economical choices for you. Doing what you're thinking doesn't make financial sense.

[Quyonmob]

How much money do you want to spend for 1 MPG combined and max of 3mpg higway?

http://www.fueleconomy.gov/feg/Find.do?action=sbs&id=13705&id=13709

Not even close to worth it.

[Jameslleary]

If you really want a v6, find a totalled 2010 camaro at the bone yard, good fuel economy, plenty of power.

[2500ak]

Swapping back to a v6 will never pay for itself. If you were going to swap in a cummins 4bt that would be more reasonable, but not a the v6.

[04bowtieguy]

I wouldnt. I would spend a couple hundred bucks and get a custom tune to optimize your current engine, thus getting better fuel economy and have power when you need it. best mpg I could get out of my 97 reg cab 5 speed v6 was 23 with intake and exhaust done, an ext cab with a 350 can get 20. A reg cab 350 driven right should have no problems pulling down similar mpg while still having the extra available power if you ever need it.

Yep. What he said. From experience, the v6 doesn't net you any savings. Most times the v8 gets the same or slightly better. The rating does not work out. Everyone I know with v8 trucks get better economy than the v6. Get the tune, save the hassle.

Sent from Hellguy's X2.

[Riseandrun]

broncoman94706, thanks for taking the beating on this:chair: I have an 89 reg.cab 8 ft bed that is in pretty good shape. I was wondering about swapping engines myself but it seems the consensus is smaller doesn't mean better. I was only thinking gas mileage. The engine I have in there has 170,000 and is a mosquito abatement vehicle:cool:

[broncoman94706]

No beating just a thought. thanks for the advice guys. For those who say they can't think of a good reason to swap a V6 in, I say pay my gas bill and you can put what ever motor you want.

Don't think I'll be doing it though, looks like it doesnt make financial sense. I think Im going to sell it and buy a crew cab with a 4.8. If Im going to get 13 mpgs I might as well have a truck that I want. Can anyone recommend a company that sells tunes to improve my MPGs. Im buying a 06 Silverado Crew cab with a 4.8. Im selling my 97 Silverado Ext cab 5.7 with 69k orig miles for 6100.00

[Quyonmob]

2wd 06 crew with a 4.8l and 3.23 or 3.42 can knock our 20mpg easy.

[TheBigMortboski]

...As long as there aren't any hills.

[Quyonmob]

I average 18-19mpg in my 07 classic Z71 in the summer, and it isn't flat here, at all.

[nick613]

spend money on new trucks to save money on gas...

[Spit]

2wd 06 crew with a 4.8l and 3.23 or 3.42 can knock our 20mpg easy.

My dad's '02 excab 4.8 could squeeze almost 22-23 mpg at 70mph in Florida (no hills like that other guy said lol). But it normally gets 19mpg at 78mph.

The 4.8 is a great more and way better than a 350 vortec or a 4.3 for that matter. Good idea trading it in on a newer truck. :D

[Dougalicious]

My RCSB 4.3 once got 23 mpg on an all interstate, 65 mph, driving behind a semi tank of gas, but realistically I average around 18-19 mixed driving.

My mom's 2005 CCSB with a 5.3 averages 17-18 mpg and has at least a ton on me plus a couple hundred pounds of stuff in the bed/back seat at most times.

If you want to swap, go with a 5.3, they can be found dirt cheap and the swap is pretty straightforward.

[Doober]

Driving from Michigan to AZ I averaged 24.5 with my '92 rcsb, soft tonneau, 4.3/4L60/3.08s, and ~28" tires... ~220,000 miles then. That was expressway, city is probably considerably less.

You would probably benefit from a minor gear change if you do mostly city driving. The added ratio would require less power to get the truck moving. I probably wouldn't go deeper than 3.73 to be on the safe side, but if I had the funds, etc. I would try that along with a 4.10.