GM Truck Club
THE PREMIER CHEVY TRUCK & SUV FORUM
Founded in 2004 ~ We're the #1 Chevy Truck & SUV Forum.
Silverado & Sierra | Tahoe & Yukon | Suburban & Yukon XL | SUV & CROSSOVER
Results 1 to 6 of 6
  1. #1
    Jr. Mechanic b-radical's Avatar
    Join Date
    Nov 2009
    Location
    San Diego, California, United States
    Posts
    130
    Blog Entries
    1

    Default Chevy 4.8L vs 5.3L

    I would like to hears others thoughts on the comparison between the 4.8L engine and the 5.3L. Obviously the 5.3 has more power but what does the 4.8L have that the 5.3L doesn't. I could be wrong but most of the silverados I've seen with superchargers or turbos are 4.8L. Is there a reason the 5.3 hasn't been built with a supercharger/ turbo? With all the bells and whistles which engine is more suitable for speed?

    Is the 4.8L a better fit in terms of transmission life?
    Why do they both get nearly the same MPG?
    I understand the 4.8 has a shorter stroke, is this an advantage?
    How do they compare in weight?

    Thanks for your input


    2000 Silverado, 4.8L, LS
    3" Dynomax cat back exhaust
    Drop-in K&N air filter
    200 amp Nations alternator
    KYB GR2 Shocks
    Bluetooth OBD2 adapter with Torque App on Samsung Note 2
    Custom Stereo System l Pioneer/ Boss door Speakers l 1200 watt Performance Teknique amp l 1 farad capacitor l 2 12" kicker comp subwoofers
    Slider rear window l Locking tailgate, de-baged l 265/75/16 Bridgestone Dueler H/L tires l Fully synthetic oil l Tinted windows
    4l65e upgrades - five pinion planetaries l HD sun shell l high performance band

  2. #2

    Default

    4.8 vs. 5.3 is fairly simple. the 4.8 is cheaper to build and chaper to sell, hence why you often see them in lower optioned trucks or in base reg cab work trucks. they can get slightly better mileage, but usually dont just form the simple fact its a 5000lb truck, and it has to work harder to do the same job the 5.3 does. if memory serves lots of the 4.8s are iron blocks and can handle turbo/super chargers better then the aluminum 5.3. i may be wrong here, going off memory of half remembered articles. the 4.8 is alos more suited for turbos and super chargers due to the fact they build more of their power at higher rpms then the 5.3.
    5.3s can be turboed and supered up, just the same as the 4.8, i dont know if its any more or less common tho.

    transmission wise they are the same.

    Alex


    2011 GMC Sierra SLE 5.3 Z71 4X4 Stealth Gray Metallic / 2004 Chevy Impala LS 3.8 Cappuccino

    Tow mirrors - Diablew Tuned - Flowmaster Regular 40 - Ready Lift 2.5' lift - BFG LT A/T K/Os - Carr Light Wing - TruckLite LED lights - Optima Red Top - 50% Front Window Tint - Line-X bedliner - Airaid MIT - Tekonsha P2 - ARS Billet Grill - Fia custom fit seat covers

  3. #3
    Master Mechanic SupplySgt's Avatar
    Join Date
    Feb 2010
    Location
    Middle TN, displaced Okie
    Posts
    764

    Default

    Most common superchargers build their power at lower RPMs actually, so from that logic the S/C would be better suited for a 5.3. However, I figure that more 4.8 owners have more of a desire to mod the motor due to the lower power output. I almost bought a newer GMC when I was on Active Duty (my idiot self settled on a V6 Dakota because I wanted a stick shift) and after I test drove a pretty nice one with a 4.8, I knew that I would be modding that motor if I had gone it. I would have been more satisfied with the 5.3 if I left everything stock.
    93 Suburban (Southern Slayer): TBI 350, 4L60E
    73 Z28 Camaro: L82, TKO 600

    KJ4CLI



    "...Death smiles at us all, all a man can do is smile back..."

  4. #4
    Sr. Apprentice BoneHead's Avatar
    Join Date
    Feb 2012
    Location
    San Angelo most of the time, Houston at others
    Posts
    61

    Default

    Dumb question about the 4.8. Is it possible to rebuild it as a 5.3? Only reason I ask is because a friend of mine might be getting a 5.3 for his 03 GMC to replace his 4.8. I was thinking about trying to get the 4.8 from him (tranny included) to put in a project car I've got. I'm planning on a rebuild anyhow, it's got 170,000 on it right now. No telling how much by the time I'm able to get it. Just kind of wondering if it was possible. I would appreciate the increase in power and mileage I would get in that car.
    1998 K1500 Suburban
    1977 Chevelle Malibu

    "I'm proud to defend your right to be an idiot!" From a friend in the military.

  5. #5

    Default

    If the bore is the same for both engines (and I believe it is), then the iron block is the same block used for both engines (an aluminum 5.3 is also available).

    The stroke is shorter because the crack and the piston rod are different than the ones used in the 5.3.

    So essentially, they are the same engine. For years, hot-roders have been playing with stroke (rods and crank) to change the power curves on an engine.

    When the bore and stroke are the same (1:1), the engine is said to be square.

    A shorter stroke usually designates a higher revving engine (over-square), also an engine that is more likely to be used in racing and, an engine that is designed to produce it's power at higher rpms.

    A longer stroked engine (usually under-square) will be used when power off the line is required, as in drag racing (or towing big loads).

    So, although not much difference in displacement, there can be significant difference in when the power kicks in, hence the 2 choices.

    GM mates the 4 speed tranny to the 4.8 and the 6 speed tranny to the 5.3.
    Ray

    '09 Avalanche LTZ - Black
    '05 Envoy XL (sold)

  6. #6
    Jr. Mechanic b-radical's Avatar
    Join Date
    Nov 2009
    Location
    San Diego, California, United States
    Posts
    130
    Blog Entries
    1

    Default

    Sweet reply, thanks Ray.


    2000 Silverado, 4.8L, LS
    3" Dynomax cat back exhaust
    Drop-in K&N air filter
    200 amp Nations alternator
    KYB GR2 Shocks
    Bluetooth OBD2 adapter with Torque App on Samsung Note 2
    Custom Stereo System l Pioneer/ Boss door Speakers l 1200 watt Performance Teknique amp l 1 farad capacitor l 2 12" kicker comp subwoofers
    Slider rear window l Locking tailgate, de-baged l 265/75/16 Bridgestone Dueler H/L tires l Fully synthetic oil l Tinted windows
    4l65e upgrades - five pinion planetaries l HD sun shell l high performance band

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •