5.3 vs 5.7 vortec engine

[Ultimax]

I have a 1998 Yukon 5.7 w/3.73 gear ratio. I would like to upgrade to a newer Yukon or Tahoe. I have test driven a couple of newer 5.3 Yukons w/3.73 gears and the 5.7 seems to have more acceleration and gets up to 65-70 MPH much faster with less throttle. Everything being equal, has anyone else noticed that the 5.7 is a stronger runner than the 5.3?

[Chris97K1500]

The max hp and torque are at different rpm ranges. The 5.7 hits it's peaks sooner, the 5.3 hits it's peak higher in the rpm range. I think the 5.7 may be a little better off the line, but once they both are reving high, the 5.3 will perform better. Chris

[350vortec]

Man this question will go on forever.I like my 350 better but the 5.3s are bad as*.I will always like the 350's better,they have been around the block a few times.Thay are reliable and great performance,and I like the lowend torque,I would rather have have my torque lower than 4,000rpm which is where the 5.3 peaks out at.You have heard my opinion but people will probably come on here sayin I am an idiot for thinkin the 350's are better.

[dogzapper]

I've had both and truly enjoy the 5.3 more. Yeah, the 5.7 might be slightly zippier, but the 5.3 seems quieter/smoother and gets MUCH better gas mileage.

 

In an era when gas is nearing two bucks a gallon, the 5.3 engine, with its 18-20 mpg on the freeway, looks pretty good.

 

Given a choice, I'd personally choose the 5.3.

 

Steve

[Hecktorx]

I've driven both and it's really hard to compare the two. They have two totally different feels and I wouldn't be unhappy with either motor.

 

IMO-The 5.3 is definately a faster motor but the 5.7 seems to handle weight better. My 5.3 averages about 17mpg while and I got about 15mpg with my 5.7.

 

It is hard to get a good comparison though. The 5.7 was a Z71 regular cab, short bed with an auto and 3.73s. The 5.3 is also a reg cab shortbed Z71 auto but has 4.10s. This probably makes it feel so much faster to me. My 03 is about 300lbs lighter then the 98 was too.

 

Now my friend had a 96 4-door Yukon. He traded it in for an 02 Yukon. Both had the same gearing, 3.73. The 02 seems to perform better, but there isn't as big of gap between performance and gas mileage that it is with the pick-ups. He says he got about 14mpg in the 96 and he's getting about 16mpg in the 02. He doesn't tow or carry heavy loads, so I don't know how they did with weight.

 

We both agree on one thing though. We both loved the old trucks but neither one of us would give up the new ones to go back to the old ones, even if we could still buy the old ones brand new.

[SilveradoWV]

They are both great engines, I think the new generation engines are faster and overall well rounded. The 350 is a torque monster though. IMO the 350 is a better engine at the lower RPMs but is lacking in power as the RPMs climb, where as the new engines arent as good at the lower RPMs but are GREAT as the RPMs climb. They just seem like 2 totally different engines, and I personally think the new engines are better suited to todays buyers who use there trucks as daily commuters and use them as trucks for towing and such. This is why I think the 5.3 is better, not because it has more power or less power or whatever, it is just better suited to Truck buyers IMO.

[350vortec]

That was well said guys

[Elwood 2000]

I too have owned both and the 5.3 is a better engine, in my opinion.

 

The torque curve for the 5.3 is a long and flat curve instead of a sharp peak with a drop off. The provides more "power" thru the RPM band and a better towing experience. If you have ever towed a load with the truck, you will know what I am talking about. The 5.3 is a very smooth engine and a good runner. While, still not proven like the 5.7, all the benifits add up to a better engine overall.

 

There will however be a special place in my heart for the 5.7. The 5.3 has large shoes to fill by trying to replace the single best all around engine ever produced.

[422 SS]

I too have owned both and the 5.3 is a better engine, in my opinion.

 

The torque curve for the 5.3 is a long and flat curve instead of a sharp peak with a drop off. The provides more "power" thru the RPM band and a better towing experience. If you have ever towed a load with the truck, you will know what I am talking about. The 5.3 is a very smooth engine and a good runner. While, still not proven like the 5.7, all the benifits add up to a better engine overall.

 

There will however be a special place in my heart for the 5.7. The 5.3 has large shoes to fill by trying to replace the single best all around engine ever produced.

A more fair comparison would be the 6.0 liter.Considering the difference in cubes a 305 would be a closer comparison to the 5.3.The 350 vortec is a torquey and reliable but can't hang with a 6.0.I have a equal comparison from 3500 cargo vans I've owned.99 350 4.10 used for in town hard work daily pulling a very heavy trailer with up to 4,000 lbs in the cargo area.Averaged 8 mpg and a dog on launch.03 6.0 4.10 doing the same job never less than 12mpg and night and day difference in acceleration.The new engines are so much smoother and more powerful that its an illusion that the 350 is stronger.I've seen dyno graphs of both and the 6.0 is stronger from idle to redline.Remember the newer trucks have torque management that cuts the power on shifts with the autos.The old trucks don't have it.This will acount for some of the seat of the pants difference illusion.Line up two 3/4 ton 2 wheel drive 4.10 geared pickups,one with a 350 the other a 6.0 and see what happens.I would not be afraid to line up next to a 8.1 HD in my 6.0 van.I have owned both and the 6.0 would stomp some ass.The 6.0 is the best small block truck engine the General has ever made.I'm not talking tradition but performance wise.