4.8L vs. 5.3L

(Forgive me if this question has been asked before)

Does the 4.8L really get any better gas mileage than the 5.3L? And how much horsepower does each engine have?

Am I better off to buy a truck that has a 4.8, or a 5.3? (Won't be doing much towing; basically just to get me from point A to point B and back.)

Thanks. :)

I HAVE THE 4.8 AND I GET 18 IN THE SUMMER AND 16+ IN THE WINTER.
I DRIVE A 2000 SILVERADO 4X4 EXTENDED CAB SHORT BED STYLESIDE. THE POWER IS PLENTY FOR ME, I DON'T TOW OR DRIVE HARD. 50 MILES A DAY COMMUTE.:2cents: :popcorn:

I don't think you could possible tell the difference fuel mileage wise between the two. If you look at the numbers (4.8 or 5.3). There is only .5 liters difference, and that is split between 8 cylinders. Now horsepower might be a noticeable difference. GM only made the Tahoe and Suburban available with the 5.3. The Silverado could come with the 4.3, 4.8, 5.3, and 6.6. Apparently enough a difference to not make the 4.8 available in the SUV's. If you are buying a pickup, the 4.8 will be fine unless you plan on pulling a big boat, then you might want to step up the the 2500 and the Duramax. Hope this helps.

Attached is some info for the 2003 vehicles.
Engine Type V8
Displacement 4.8L 293 CID
RPO LR4
VIN V
Bore 96.0-96.018 mm (3.779-3.78 in)
Stroke 83.0 mm (3.268 in)
Compression Ratio 9.47:1


Engine Type V8
Displacement 5.3L 325 CID
RPO LM7
VIN T
Bore 96.0-96.018 mm (3.779-3.78 in)
Stroke 92.0 mm (3.622 in)
Compression Ratio 9.49:1


Engine Type V8
Displacement 5.3L 325 CID
RPO L59
VIN Z
Bore 96.0-96.018 mm (3.779-3.78 in)
Stroke 92.0 mm (3.622 in)
Compression Ratio 9.49:1

Like Hogster (But without the CAPS) I too have the 4.8 in my '02
I was getting 18 mpg everything being stock
I added BFG ta/ko's and my mileage dropped to 16-17 range.

My friend @ work has an '03 Z71 with stock tires; and he gets 16 in his totally stock rig (Stock tires also)
(Edit; I'm adding for those who don't know.. Z71 comes standard with the 5.3; not the 4.8)

Hope it helps.
-Tom D.

I have an 02 4.8. With 255/75/16's I got around 18-20 mpg hwy. With 265/75/16 BFG A/T's I get 14-15 mpg hwy 13 mpg city. Plenty power for every day driving and light towing.

From what I've heard from several sources, you probably won't be able to tell a difference mileage wise, especially if you have a heavy foot it all seems to average out. So, what it boils down to is can you afford the price difference, or how good a deal is it if used. I mean, if you can afford it and it doesn't seem to cost more in mpg, why not buy it.

Just so you know, I bought the 4.3 6 cyl because I'm a cheapskate and don't tow and am not in that big a hurry to pass the guy at the stoplight. Plenty of power to pull itself very well. With 1500lbs in the back, it suddenly gets weak feeling, but I've only done that once in the 3 years I've owned it. My normal weight is about 500lbs in the back, and I never know that's there.

Ok, I take that back, with 500 lbs in the back, it drives better b/c the rear tires actually have some traction.

I don't think you could possible tell the difference fuel mileage wise between the two. If you look at the numbers (4.8 or 5.3). There is only .5 liters difference, and that is split between 8 cylinders. Now horsepower might be a noticeable difference. GM only made the Tahoe and Suburban available with the 5.3. The Silverado could come with the 4.3, 4.8, 5.3, and 6.6. Apparently enough a difference to not make the 4.8 available in the SUV's. If you are buying a pickup, the 4.8 will be fine unless you plan on pulling a big boat, then you might want to step up the the 2500 and the Duramax. Hope this helps.

Attached is some info for the 2003 vehicles.

Engine Type V8
Displacement 4.8L 293 CID
RPO LR4
VIN V
Bore 96.0-96.018 mm (3.779-3.78 in)
Stroke 83.0 mm (3.268 in)
Compression Ratio 9.47:1
Engine Type V8
Displacement 5.3L 325 CID
RPO LM7
VIN T
Bore 96.0-96.018 mm (3.779-3.78 in)
Stroke 92.0 mm (3.622 in)
Compression Ratio 9.49:1
Engine Type V8
Displacement 5.3L 325 CID
RPO L59
VIN Z
Bore 96.0-96.018 mm (3.779-3.78 in)
Stroke 92.0 mm (3.622 in)
Compression Ratio 9.49:1

Not to sound like a dumbass(too late).. What is RPO???:confused:

Regular Production Order... the codes that specify options. Usually one letter followed by two numbers: Z71, Z28, Z06, G80, etc, etc.