I found a 99 2wd rcsb Sierra with a 4.8 pretty clean truck low miles. Does the 99 4.8 suck that bad? I had an 04 with one in it years ago it was ok. But I do remember my 99 z71 with a 5.3 being more than a slug. I guess I'm just wondering how much I may not like the 4.8 until I make some big changes. Better yet would I be better off with an 03 and up. I'm all ears let's here some pro and con

 

It's not going to as fast/fun as a 5.3 because of the power difference but maybe it's opinion based for the slug comment.

The plus side is that it's a light truck being 2wd. A cam swap, some nice gears and a tune would make it a real rev happy 4.8.

 

I know in fairness the 5.3 z71 was bigger and heavier. I guess I'm asking to should I get the truck and just not bother with the 4.8 and do a 6.0 swap. I'm rusty on my GMT 800 stats but what was the power difference In the early 4.8's and 5.3's. I use to know but a lot has been forgotten.

 

For 99 it was 255/285ish and the 5.3 was 270/315.

00-03 was like 270ish/285 and the 5.3 was 285/325.

04+ got a power bump above those as well with better cylinder heads and tuning.

99's got the worst end of the deal with very mild calibrations and they had 21lb/hr injectors compared to the 00+ that got 25lb/hr and allow for more power.

 

A truck is a truck, go for styling and what you can affoard over power...

Essentially all the truck motors were the same with fairly mild changes over the course of the GMT 800 run.

As mentioned the 99's 4.8 had smaller injectors.

In 03 all truck motors received coated piston skirts to help with the Piston slap on startup.

In 05 all truck motors received Floating Pin rods. Only the LQ9 received them first in 03.

The only Gen3 engine to receive the 799/243 heads were the L33 in 2005-2007 Classic and those only came in the Extended cab 4x4 trucks.

In 06 the Gen 4 engines came with them in the NNBS SUV's and in 07 on the NNBS trucks.

 

So many trucks out there no way I would unless the plan was a motor swap right away. You are limited on hp even if you turboed it with an early model but that could certainly work and still be plenty fast for a DD. I just couldn't drive a 16-17 second truck even for a little bit lol. If its nice though and cheap enough great place to start!