05 Vortec 4.8l V8

[newfiecharger]

HI,

I just purchased a 2005 Silverado 4X4 4.8l V8 with 35000km. I was woundering about the Vortec 4.8l reliability, and fuel economy? Should I let the Oil Life Monitor tell me when to change the oil? I can't seem to find any info on this motor on BITOG or working oil reports (not sure if I'm searching wright. If this as been discussed before please post some links to teach a new BITOG user.

Thanks

 

[MrCritical]

Reliability is excellent. Go by the monitor, but check oil level periodically, more often if you tow. It's the same basic engine as the 5.3 Hwy fuel mileage 20-22mpg with cruise, some less with 4 door due to weight.

 

[ekpolk]

No comment either way, as I don't know all that much about these engines. That said, I've wondered for a long time about why this engine even exists at all. It appears that it pretty much gets the same fuel economy as the 5.3L (but is better than the 6.0). So why does GM bother having both the 5.3 and the 4.8???

 

[Jim 5]

In a lighter regular cab 2wd truck, the 4.8 will deliver better fuel economy, and so will the 4.3L v6 if I'm not mistaken. If the 4.8 has to deal with additional load/weight, then the 5.3 will do as well or better while delivering more power.

I think it costs more to buy the 5.3 which is simply a stroked 4.8, though the difference in cost to manufacture would appear to me to be negligible - different crankshaft and perhaps connecting rods. Incidentally, the 6.0 is just a bored 5.3. Without looking at the serial number, one wouldn't be able to tell the difference between a 4.8, a 5.3 and a 6.0 by looking at the outside.

These are very reliable engines by north american manufacturers' standards. The only issues I am aware of are some piston slap issues until the 2004 model year.

My 5.3 UOA's confirm that the GM OLM is very reliable and conservative. In my own opinion, you can rely on it. Other UOA's of LS series GM v8's based on the OLM are consistent with that conclusion.

Bill_in_Utah of this discussion board ran his 4.8 powered silverado 4x4 for a number of years with fuel economy in the low 20's if I'm not mistaken, and had outstanding UOA's on this engine (like he does on all of his vehicles). You could search by his username and with search terms like "4.8" or "silverado".

 

[Drew99GT]

Good engines IMO, based in the LS-series of GM V-8s (LS1, lS2 etc.). No intake gasket leak issues. Ballsy with good fuel mileage.

 

[bretfraz]

My thought is GM offered the 4.8L V8 as a replacement for the long-standing 4.3L V6. I have not researched this but I'll bet the V6 could not keep up with modern fuel economy and emissions requirements, so GM developed a smaller version of the 5.3/6.0 family instead of spending the mega$$$ to develop an all new high torque "truck" V6.

Most of the old 4.3L applications (S-10, Astro, etc) have been discontinued and the competition was moving to bigger, more powerful engines. Offering a small V8 in certain applications gives GM a marketing edge while keeping costs down. Most of the 4.3L buyers were commercial customers (service vans, work trucks) anyway. They'd buy a V8 if its cost wasn't too high and mileage was comparable to the old V6.

I think the 4.8L V8 is a great engine in a commercial application. Consumers and others have the larger V8's to choose from. GM has a big edge over Ford and Dodge without spending big bucks.

My 5.3L has been bulletproof for 65,000 miles now. They seem to prefer 10W-30 over the OE recommended 5W-30. Piston slap isn't a big issue on '04 and newer models. The OLM seems pretty accurate and I use it as a reliable guide.

 

[GMBoy]

Originally Posted By: Jim 5
In a lighter regular cab 2wd truck, the 4.8 will deliver better fuel economy, and so will the 4.3L v6 if I'm not mistaken. If the 4.8 has to deal with additional load/weight, then the 5.3 will do as well or better while delivering more power.

I think it costs more to buy the 5.3 which is simply a stroked 4.8, though the difference in cost to manufacture would appear to me to be negligible - different crankshaft and perhaps connecting rods. Incidentally, the 6.0 is just a bored 5.3. Without looking at the serial number, one wouldn't be able to tell the difference between a 4.8, a 5.3 and a 6.0 by looking at the outside.

These are very reliable engines by north american manufacturers' standards. The only issues I am aware of are some piston slap issues until the 2004 model year.

My 5.3 UOA's confirm that the GM OLM is very reliable and conservative. In my own opinion, you can rely on it. Other UOA's of LS series GM v8's based on the OLM are consistent with that conclusion.

Bill_in_Utah of this discussion board ran his 4.8 powered silverado 4x4 for a number of years with fuel economy in the low 20's if I'm not mistaken, and had outstanding UOA's on this engine (like he does on all of his vehicles). You could search by his username and with search terms like "4.8" or "silverado".



I may be wrong here, but I thought the 5.3 was mandatory with 4x4. Atleast that was the deal when I was truck shopping in 2006.

 

[newfiecharger]

So far (the last 400km) the truck as been pretty good. Does not go over 2000rpm at 100km (~60mph) and gas is not bad. The gears are 3.42 and G80 locker, I guess this will help with fuel economy. The tranmission is a the 4L60-E, which feels pretty strong.

 

[newfiecharger]

Gas here in Newfoundland Canada is $1.17 per liter. We have seen a lot higher, I think we hit about 1.30 at one point last year.

 

[Bill in Utah]

Quote:
I may be wrong here, but I thought the 5.3 was mandatory with 4x4. Atleast that was the deal when I was truck shopping in 2006.


My 4.8l in a 2000 Silverado is a excellent engine. In a 5000lb 4x4 ext cab truck getting 20+ MPG and had great power.

My Mom has the same truck engine combo in her 2002.

I'd buy another in a heartbeat.

From the Chevy.com web site:

Vortec 4.8L V8 Engine

Vortec 4.8L V8 engine features:

* 295 horsepower @ 5600 rpm
* 305 lb.-ft. of torque @ 4800 rpm
* EPA estimated MPG 14 city/19 highway in 2WD models
* EPA estimated MPG 14 city/18 highway in 4x4 models

So it is still available.

To the OP, Follow the OLM with good conventional oil and you'll be fine.

Bill

 

[MrCritical]

We've had 4x4 crew cabs with the 4.8, so I guess the 5.3 isn't standard with 4x's.

EPA rates the 4.8 higher in hiway mileage than the 4.3 v6.

 

[ekpolk]

Originally Posted By: MrCritical
We've had 4x4 crew cabs with the 4.8, so I guess the 5.3 isn't standard with 4x's.

EPA rates the 4.8 higher in hiway mileage than the 4.3 v6.


According to the data that's showing at Chevrolet.com today, that's correct, but it's also true that the 5.3L gets even better mileage than the 4.8L. I can't tell for sure, but I'd guess that it's because the 5.3L gets the cylinder deactivation feature, whereas the 4.8L does not??? If that's correct, I remain baffled as to why the 4.8L is there as the small "economical" V-8, while it lacks the most obvious mileage enhancer (beyond its size). If they want to make a max fuel econ V-8, wouldn't that seem to point toward a 4.8L with the cylinder deactivation feature from the 5.3L???

 

[MrCritical]

Try to tell GM that. Their hybrid has the 6.2 gasoline.

 

[wapacz]

Its a 6 liter in the hybrid. The larger displacement most likely increases the amount of time it can spend with deactivated cylinders. Which would increase fuel economy.

my guess for the 4.8 is that it is a mix displacement and the amount of them they sell.

 

[ekpolk]

Originally Posted By: wapacz
Its a 6 liter in the hybrid. The larger displacement most likely increases the amount of time it can spend with deactivated cylinders. Which would increase fuel economy.

my guess for the 4.8 is that it is a mix displacement and the amount of them they sell.



Car and Driver has an article on the Tahoe Hybrid in the latest issue (March 2008). The author states that GM used the 6.0L version of the engine for the hybrid because of torque advantage at lower rpms.

I'm sure that the 4.8 is a fine engine, but I still don't get why it's (still) there. It has the same external dimensions at the larger displacement versions, produces lower hp/tq, and lower mpgs.

I'm not sure GMBoy will be at liberty to comment, but if he is...

 

[mrsilv04]

Well, how many years did GM offer the choice of a 5.0 V8 and a 5.7 V8 in their trucks?

Yet everyone sits around here and wonders why they've offered the 4.8 and the 5.3 for the last several years?

Duh! They've done it for as long as I can remember with the 5.0 and the 5.7, before the current line-up.

This is nothing new, folks.

I have an '04 with a 5.3, and my neighbor has an '05 with a 4.8. Both trucks are 2 wheel drive, extended cabs. He drove my truck one evening, and could tell by the seat of his pants that my truck had more engine under the hood, just by driving it.

BTW, we get the same gas mileage.

 

[ekpolk]

Originally Posted By: mrsilv04
Well, how many years did GM offer the choice of a 5.0 V8 and a 5.7 V8 in their trucks?

Yet everyone sits around here and wonders why they've offered the 4.8 and the 5.3 for the last several years?

Duh! They've done it for as long as I can remember with the 5.0 and the 5.7, before the current line-up.

This is nothing new, folks.

I have an '04 with a 5.3, and my neighbor has an '05 with a 4.8. Both trucks are 2 wheel drive, extended cabs. He drove my truck one evening, and could tell by the seat of his pants that my truck had more engine under the hood, just by driving it.

BTW, we get the same gas mileage.


No one suggested that engine choices are some new strange thing, and I think you're missing the point of my question. To put it in a very tight nutshell, what's the point of a smaller-displacement engine choice that puts out less hp and tq, and gets slightly worse gas mileage than it's larger displacement cousins? Most typically, smaller displacement engine choices produce less output than larger engines, but usually, they offer the benefit of getting better fuel economy.

Having the smaller engine offer worse fuel economy IS something unusual.

EDIT: I might add that it's a phenomenon that's not unique to the Chevy line. Another example exists with the 4WD versions of the Toyota RAV-4. The V-6 version (with the large 3.5L no less) actually posts better EPA highway FE than the 2.4L I-4 version does.

 

[Jim 5]

What I don't understand is why a de-stroked 5.3 such as the 4.8 (this being the only real difference) should cost a penny less to buy or manufacture than the 5.3.

In fact, since the 5.3 is the most common and therefore the highest production option, and given that the 4.8 and 5.3 are basically identical (apart from the stroke), then the 5.3 should be, based upon economies of scale, the most inexpensive engine option.

It seems to be marketing, and as an uniformed observer, it appears like the 4.8 exists so that GM can charge "extra" for the 5.3 that most people will choose anyway.

I don't know what I'm talking about here, and am open to being corrected, but I see no other explanation.

 

[glennc]

I think a lot of car companies do this. BMW does it all the time, and they especially like to confuse you as to what engine you are actually getting. For example the 325i in the '80's had a 2.5l, makes sense, but the 325e had a detuned 2.7l that was also used in the 528e, whereas the 3.5l engine used in the 535i was also used, with a turbo, in the 745i. The recent 325i and a 330i both used 3.0l engines in different states of tune for a while, until of course they changed it to something else that is probably equally confusing. I'd need a cheat sheet to keep track of exactly what they put in each car, and there's rarely any price justification other than ensuring that the less expensive cars are also less appealing.

It's just marketing....

 

[ekpolk]

I'd agree that there's probably a strong marketing influence going on here. But I remained baffled by the continued existence of BOTH the 4.3L V-6 and the 4.8L V-8 in the Silverado line (and the lone 4.8L in the Tahoe line). Wouldn't it just be cheaper for GM to kill one of the engines, thereby cleaning up the supply line, inventory, etc., and leave the survivor to alone fill the role of the "cheap" bottom-of-the-line economy engine? Maybe having both allows sales to commercial buyers who insist upon having a six for their ultra-cheap W/Ts while also having a "higher tech" alternative for those buyers who might value that. Dunno, just me thinking on the fly (usually a very dangerous thing...).