GMC 5.3 engines

[gilby]

I"m looking at buying a 2002 GMC pick up. Anything I should be concerned about with this engine. How about the transmissions in these, any negative or positive comments on these, Thanks gilby.

[federline]

I have the 4.8L. The 5.3 is a bored out version of the 4.8L. I bought my 1999 Silverado used, when it was in need of a tune up; and I experienced the only serious transmission fault I know of for these trucks. Once through those, this truck has been troublefree. I have 120,000 miles on mine - replaced the fuel pump, O2 sensors, and had the transmission kit installed that I mention below. That's it. It is running like a champ, still an almost perfect truck.

This is all from memory, so bear with me. Also, I am just a shadetree mechanic, not a pro.

These engines and transmissions have very few chronic flaws. You can tell if the vehicle is afflicted with any (not all are) with a test drive that starts from a completely cold engine and brings everything up to highway operating temperature (engine and transmission).

1) 4.8L, 5.3L and 6.0L: This family of engines are computer-tuned to the brink of lean-ness with many sensors, resulting in great MPG. The downside is that any lack of maintenance of air intake system, fuel supply or spark can make them perform like crap, usually from running too lean. If the Check Engine light comes on, you should get a code puller - it will may read that one or both of the banks are too lean.

--> Once you are at operating temperature, get on an open road or the freeway and mash it down through one or two upshifts (1-2 or 2-3 is best). If it detonates, heasitates, or backfires during shifts, it must get a tune a tune up. If it does, it may even set a Check Engine code.

--> The typical culprits for this are a worn out fuel pump or fuel pressure regulator (low fuel pressure) or a dirty MAF (mass airflow sensor - computer can't figure out how much air is coming in to match the fuel with). For the fuel pump, the easiest way to replace it is to order one online (much cheaper than dealer), and pull the bed off the truck since the pump is in the top of the fuel tank. (Dealers charge full labor estimate for doing it with the bed left on, even thought most take it off.) The fuel pressure regulator is easy to get at under the hood for replacement, too. You easily can test the fuel pressure under the hood with a special tester from an autoparts store or shop - it should be something like 56 psi - below 50 psi and you'll never get it to run good under load. For the MAF, you can carefully remove it, let it cool ALL THE WAY DOWN, and clean the delicate wires with aerosol brake cleaner solvent.

--> For this condition, the shotgun approach is to replace/clean the MAF (new MAF is $150, brake cleaner is $5), replace the fuel pressure regulator ($15), replace the fuel pump ($75-$150), replace the air filter, clean out the air intake and butterfly with fuel injected engine intake cleaner (not carb cleaner) (they tend to soot up), and replace the front oxygen sensors. I also pull a couple fuses in the control panel under the hood to clear out the computer memory. Oh yeah, and make sure you don't use cheap plugs - the only ones I've found that work well are the AC Delco platinum plugs from the dealer, 8 will run about $50.

2) Also, if these engines run too lean for too long (didn't get tune ups or new parts when it needed them), they may get concrete-like carbon deposits at the top of the piston stoke.

--> When it is cold, start it up and let it warm up for 2-3 minutes while you listen under the hood. If it has carbon deposits, one or more cylinders will "tick". It's more than a lifter tick, it's like a diesel noise almost, 'cause it is the piston tapping the deposits. If it goes away within a minute or two, it is treatable with regular Sea Foam applications through the PCV vacuum line and fuel supply, I do mine every 5000 miles. The reason it goes away in this case is because the parts expand as they heat up and clearance is achieved. If it doesn't go away when at normal operating temp and/or is really loud, I'd pass on it - some of these engines have self-destructed when let to get this bad.

3) The auto transmission in some 1/2 ton GM trucks may display a behavior where they will "SLAM" into gears as it shifts. This is usually only noticable when the transmission gets nice and hot, unless it has been let go way too long. Wintertime driving will mask this problem if it exists because the transmission won't heat up all the way. I made it through the winter after the fall when it started without issue, and then it came back in the spring.

The problem, if it exists, results from a solenoid piston in the transmission wearing out the valve it opens and closes normally, leading to fluid leakage through the valve body when it is shifting. This results in slippage on the plates due to low hydraulic pressure, which makes the computer think the transmission is slipping.

It then, as a self preservation measure, goes into "limp home mode" and jacks the internal pressure WAY UP, resulting in shift SLAMS. If it slips for more than 6 seconds (I think) straight, it will light up the Check Engine light. The code pulled from the computer will be a P1087. BUT - if it slips for less than 6 seconds and goes into limp-home mode, it will throw a P1087 WITHOUT lighting the Check Engine light. So, if you suspect this at all, have the codes pulled from the computer.

This tranny problem typically crops up around 80,000 miles like clockwork, if the truck is going to get it. As this problem gets worse, the transmission will start dropping out of overdrive at highway speeds.

The fix at a dealer is to rebuild or replace the entire transmission. However, it is such a common problem, there is a rebuild kit (boring jig and new steel valve sleeve) that any GOOD transmission shop can install for $400 or less, bottom line.

I hope my experiences help you find a good truck. I am really happy with mine.

[nluchau]

You can never go wrong with a Vortec 5.3, I love mine

[caseymcq]

I have an '04 with the 5.3. I love it. It is quiet, starts and runs like a top. Very smooth running. I just bought it in January so I haven't had to oprotunity to pull my boat with it yet. I have 3.73 gears, my milage has been high 16's to low 17's mpg with light use of the 4WD. I will be anxious to see what I get once the weather warms up.

[delcecchi]

Sounds like a bad design to me. Marginal engine and chronic transmission problems. reminds me of my 77 impala with 200 automatic. Is this kind of stuff common with GM products? I thought their problems were due to the union and bad management. This sounds like poor engineering also.

[Capt. H (Ret.)]

I didn't know they produced the 5.3 in 1999 unless it was later in the year. I know that the 5.7 was the main engine for most GM products before the switch to the 5.3. The people I know that have the 5.3 like them and I haven't heard them complain about any problems.

[jwhjr]

I just turned 30K on my 04, and I have had no issues. It pulls the boat great, and I've had it loaded up with wood, rock etc. and it runs just as strong.

[John Mickish]

Quote:

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Sounds like a bad design to me. Marginal engine and chronic transmission problems. reminds me of my 77 impala with 200 automatic. Is this kind of stuff common with GM products? I thought their problems were due to the union and bad management. This sounds like poor engineering also.

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You have got to be kidding. What is it you drive?

[delcecchi]

an explorer and a honda accord. Had a bellyfull of GM with that fine Chevy Impala. Had 70k and a "rebuilt" transmission when I bought it. Tranny went out, had a new or rebuilt one put in by dealer. Put in a rear end because it clunked so bad going around corners. Fortunately got that one at a junkyard, so it wasn't too expensive. In a few more years the tranny was losing oil and slipping terrible. Finally got 50 bucks for it at a junkyard. Had maybe 120k on it.

That was the model year they put the 200 series chevy 2 trannies in V8 Impalas.

Never again.

I have a buddy who feels the same way about fords. And my Tempo was no prize, for sure. But if you want to discuss fine engineering, GM takes the prize.

I'll just leave it at that.

[John Mickish]

The level of engineering on todays vehicles (all manufacturers) is so far advanced compared to as little as 5 years ago. You cannot take your experiences with a mid 1970's vehicle and think they still do it the same way today. With the global market and technology sharing that goes on today all vehicles are good. GM has had techology trade agreements with both Toyota and Honda in recent years, Ford is in cahoots with Mazda and Volvo and Dodge has it's German connection.

I do agree with you, the 200 tranny was junk. The 700R4 wasn't much better but the 4L60E is light years ahead of them.

[federline]

Capt - They had the 5.3 in 1999 - but I have a 1999 with the 4.8. The original poster is inquiring about a 2002 with a 5.3. In 1999, both the older C/K series, and the Silverado 1500 series were built. The plant lines cut over mid year. Makes getting parts for a 1999 tricky if the guy behind the counter doesn't realize this... the usual line I get back is "4.8L?! There was no 4.8L 1999!" To which I reply "go back and pick the right model and you'll see it."

[Kevin Turner]

I've had several 5.3 GMs. Nothn' outta the ordinary as far as repairs.

Darn fine power plant.

[castindad]

federline looking at a 2005 chev. malibu 4cyl. with 10,000 miles on any info would be helpful castindad thanks

[castindad]

federline what is the value of a 1992 dodge caravan motor has 110,00 mile motor not the best? castindad?

[hanson]

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I didn't know they produced the 5.3 in 1999 unless it was later in the year.

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Federline touched on it but yes, they had the 5.3liter in 1999. I have a 99 GMC Sierra (new body style) with a 5.3liter . I've been extremely happy with the truck.

I've had my fuel pump & fuel pressure regulator replaced as well.

Dan Thiem gave me some good advice and that was to simply replace your fuel filter more frequently, due to the fact that trucks go through A LOT more gas than other vehicles.

[Jeremy airjer W]

4 cylinder Malibu - underpowered

92 Caravan - overpriced at any price! What size engine? Did they have the mitsubishi 2.6 litre in 92?

[Whoaru99]

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The 700R4 wasn't much better but the 4L60E is light years ahead of them.

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4L60E is more or less an electronic 700R4 isn't it?

[Whoaru99]

You want to talk about engineering marvels, well try the early model Eagle Vision/Dodge Intrepid/Chrysler Concorde.

Have your front end (tie-rod ends/bushings, swaybar links, etc) replaced every 50-60K...

Don't know if the newer ones (except Eagle Vision, of course) are any better, but I'd sure hope so.

I finally got rid of mine after the left front wheel more or less fell off when the lower ball joint came apart with no warning. Just darn glad I was only going about 10MPH at the time.

Too bad though cause it was a good-looking car and that 3.5L 24-valve had pretty good pep for it's time with good highway MPG too.

[John Mickish]

Yes, the 4L60E is the evolution of the 700R4. It's much more than a 700 with electronics though. There where many updates to the clutches, drums, shafts and seals to be able to handle the power of the new engines. Like most things in life and cars, if used properly it will last a long time, but treat it badly and it will get you back!

[Whoaru99]

Yup, 195K on mine (4L60E) and still going. Regularly pulled a fairly heavy 7x16 enclosed trailer for a good portion of it's life.

[Gus]

80k on the clock for my 2003 5.3L and zero problems other than a power steering pump under warranty and a Check engine light that comes on when it's hot outside. Something in the evaporative systems emmissions is goofy and I get the CEL only in hot weather. Overall, I'd rate the truck a 7. I'm not terribly impressed with it, but I don't think there are any trucks out there besides a toyota that would get a higher score from me. Overall it does get me and my gear from one place to another in comfort. I thought my tahoe with a 5.7L motor towed loads easier without needing to drop it into 3rd.

[federline]

Who are U: 195K! That is *exactly* the reason I bought a GM 1/2 ton. I know many GM 4x4 truck owners who have seen 200K, it just won me over.

[gilby]

Thanks for all the good info, just so you all know, I did purchase the truck and really like it. I know I will be very happy with the truck, the truck is a 2wd, my second one. I"m hoping for good mileage.I always got 18mpg on highway with my old truck,without pulling the boat. should get 20mpg on highway with this one.I'm hoping. Thanks,gilby.

[iffwalleyes]

I had a 2002 and it was a awesome truck. I put 110,000 on it in 2.5 years. I had next to no problems other than standard stuff. No engine and No tranny problems. I trade for another 2002 but this on is a D-Max and it too is awesome. Chevy will be in my garage far into the future. It is amazing the power the 5.3 puts out it is fast and quick. I know several people that owe these and pretty much everyone I know loves them.