Gen Iii Engines (4.8, 5.3, 6.0, Etc)

gmchevroletruck · May 11, 2009

Have always been very impressed with the longevity of many 350 5.7 engines, and we've all seen the buzz on some of the million mile trucks and vans with that engine in it. I have a truck with a 350 also, and have been impressed with it's longevity as well, as it has 270k on it now and seems strong (although the previous owner seemingly lacked on the oil changes, since it's pitch black under the valve cover).

Having a truck with the 5.3 in it also, I snooped around the net to find some info about longevity on these engines, and found some interesting info and quite a positive review of these newer engines, on a Jeep engine swap website, of all things. The link is below, it was pretty interesting to me, maybe you'll find it informative and useful also?

http://www.novak-adapt.com/knowledge/gm_ge...tion_III_v8.htm

One of the things stated on that page is, under the heading "The Result", is: 400,000 mile longevity design. There doesn't seem to be any info available anywhere as to how they came to that conclusion, or what it is based on, although I did find another site once that mentioned trucks at the GM Proving Grounds with those engines that had over 400k on them (religiously maintained and controlled environments for sure).

Was wondering, does anyone know of any cases where these engines, although fairly new, have racked up massive miles (300k plus) without a re-build?

Zembonez · May 11, 2009

There have been a bunch of threads in here on this.

To sum it up, there are many of these engines well over 200K and going strong.

Here's a pic of my delivery driver's 5.3 99 Sierra from last year.

gmchevroletruck · May 11, 2009

There have been a bunch of threads in here on this.

To sum it up, there are many of these engines well over 200K and going strong.

Here's a pic of my delivery driver's 5.3 99 Sierra from last year.

wow! Quite impressive...I'm assuming no rebuild?

It seems with any engine, the key is that once you start it, just never shut it off, keep driving forever...it's those cold starts that kill it.

No matter how you look at it, for a gasoine engine, that is impressive

Zembonez · May 11, 2009

wow! Quite impressive...I'm assuming no rebuild?

It seems with any engine, the key is that once you start it, just never shut it off, keep driving forever...it's those cold starts that kill it.

No matter how you look at it, for a gasoine engine, that is impressive

Those were original miles. He has since replaced the engine, but it went a while beyond that. Pretty impressive.

gmchevroletruck · May 11, 2009

wow! Quite impressive...I'm assuming no rebuild?

It seems with any engine, the key is that once you start it, just never shut it off, keep driving forever...it's those cold starts that kill it.

No matter how you look at it, for a gasoine engine, that is impressive

Those were original miles. He has since replaced the engine, but it went a while beyond that. Pretty impressive.

Absolutely impressive. I'll look for some other threads on here about the topic...any other info out there?

mr_bots · May 12, 2009

The Gen III have been proven to be incredibly reliable, possibly more reliable than a 350. The judgment is still out on the Gen IVs with the addition of AFM and/or VVT on some of them.

Ranger · May 12, 2009

One of the GCs I work for has an 06 2500hd with well over 200k, and this truck is pretty abused...Still runs good though, I jsut saw it a few hours ago with a dump trailer loaded with crap. And that's with the 6.0L...

gmchevroletruck · May 12, 2009

...trying to decide if I should keep the truck or not...130k on it now, runs well although I just put an alternator in it, and possibly an a.c. problem now, to be determined...not major issues, but the first I've encountered on this truck, I believe it's the original tranny (bought it with 89k on it). Has been a solid truck so far, but I've seen some on here have replaced 4 transmissions by 200k (averages out to one every 50k?! - sounds very odd, not typical of my past GM experiences)...If I can get 250k out of it i will be more than happy

gmchevroletruck · May 12, 2009

One of the GCs I work for has an 06 2500hd with well over 200k, and this truck is pretty abused...Still runs good though, I jsut saw it a few hours ago with a dump trailer loaded with crap. And that's with the 6.0L...

Always encouraging to hear of trucks that have been abused, and still plug on...that's awesome.

There are theories out there that say, the more you pamper it, the more problems you will have, and the less you pamper it the longer it will last...I find that pretty hard to believe from a logical standpoint, but...there are cases that almost support that lol! I just can't bring myself to try that on purpose...I use it for what I need out of it, but try to maintain it too

dcschneider · May 12, 2009

I have 170k on my 03 5.3L running as strong as ever

Ranger · May 12, 2009

One of the GCs I work for has an 06 2500hd with well over 200k, and this truck is pretty abused...Still runs good though, I jsut saw it a few hours ago with a dump trailer loaded with crap. And that's with the 6.0L...

Always encouraging to hear of trucks that have been abused, and still plug on...that's awesome.

There are theories out there that say, the more you pamper it, the more problems you will have, and the less you pamper it the longer it will last...I find that pretty hard to believe from a logical standpoint, but...there are cases that almost support that lol! I just can't bring myself to try that on purpose...I use it for what I need out of it, but try to maintain it too

Well the first 100k or so were as a tow rig for one of the main guys for the GC, who pulled a popup camper to Tennessee quite a few times...Then the GC bought out the truck when he bought a new 07 2500hd (actually it was exactly the same configuration- ext cab short bed 4x4 gasser red in color, same options thereabout that I saw)...He's an older guy who probably was a bit easier on it but now it's a real beater- in the 2 years the company has been using it for a runner/tow-er the bed has been seriously mangled, someone backed the tail light into something, and it seriously smells inside from all the smokers...But it still plugs on and I was talking to the guy driving it earlier and he says it's running pretty damn good.

gmchevroletruck · May 12, 2009

One of the GCs I work for has an 06 2500hd with well over 200k, and this truck is pretty abused...Still runs good though, I jsut saw it a few hours ago with a dump trailer loaded with crap. And that's with the 6.0L...

Always encouraging to hear of trucks that have been abused, and still plug on...that's awesome.

There are theories out there that say, the more you pamper it, the more problems you will have, and the less you pamper it the longer it will last...I find that pretty hard to believe from a logical standpoint, but...there are cases that almost support that lol! I just can't bring myself to try that on purpose...I use it for what I need out of it, but try to maintain it too

Well the first 100k or so were as a tow rig for one of the main guys for the GC, who pulled a popup camper to Tennessee quite a few times...Then the GC bought out the truck when he bought a new 07 2500hd (actually it was exactly the same configuration- ext cab short bed 4x4 gasser red in color, same options thereabout that I saw)...He's an older guy who probably was a bit easier on it but now it's a real beater- in the 2 years the company has been using it for a runner/tow-er the bed has been seriously mangled, someone backed the tail light into something, and it seriously smells inside from all the smokers...But it still plugs on and I was talking to the guy driving it earlier and he says it's running pretty damn good.

That's funny...poor thing probably got a bit of T.L.C. in it's early life with the first owner, and now it's being hammered on LOL...quite a testimony to the reliability of GM trucks...I'd be curious to see how long this one keeps plugging without major mechanical repairs...Keep on truckin!

carneyman · May 12, 2009

It seems with any engine, the key is that once you start it, just never shut it off, keep driving forever...it's those cold starts that kill it.

No matter how you look at it, for a gasoine engine, that is impressive

Pretty much. Back on the farm we run 350's, 454's, and 496/502s for irrigation, and they run 24/7, shutting them off only if we get a big rain or to change the oil/spark plugs. Those things run straight for 5-7 months depending on the crop, and they usually last 3-4 years before a rebuild is necessary. Thats running at around 2000 rpm. Not too shabby.

gmchevroletruck · May 12, 2009

It seems with any engine, the key is that once you start it, just never shut it off, keep driving forever...it's those cold starts that kill it.

No matter how you look at it, for a gasoine engine, that is impressive

Pretty much. Back on the farm we run 350's, 454's, and 496/502s for irrigation, and they run 24/7, shutting them off only if we get a big rain or to change the oil/spark plugs. Those things run straight for 5-7 months depending on the crop, and they usually last 3-4 years before a rebuild is necessary. Thats running at around 2000 rpm. Not too shabby.

wow, not too shabby at all...in fact, (and I know this is a loose interpretation, but..), 7 months (210 days) a year for 4 years equals 840 days, or 20,160 hours at 2000rpm, which could be 65 mph on the road, and at that rate, it's equal to 1,310,400 miles. Again, loose interpretation, but very impressive

Ranger · May 12, 2009

Well motors used for generation and at a steady RPM are a lot different than those used in autos...Autos are subject to very different RPM ranges, heat cycles, vibrations from roads, and stress levels (pulling trailers or hauling heavy items). There are some Diesel motors at the airport that have been there more than 15 years and they have way over 50,000 hours (just a guess, didn't look at their hourmeters but they were there for a long time) running almost constantly, only being shut down for inspection/maintenace every 18 months. They were some huge beasts, and one of the maintenace guys told me just one of them could run a small town and they had about 8.