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5.3 replacement

imaniguana

Charter Member
SM 2004
SM 2003
Full Member
Joined
Jan 15, 2002
Messages
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Location
Philly area
The time has come to replace my 5.3.  It only has 165k on the clock, but it's making some nasty noises.  My mechanic says it's days are numbered.  He said for the money, he didn't recommend spending $ troubleshooting it.  He recommends going with a 350 reman.  He said that's what they typically replace the 5.3s with.

I'm looking for better torque in the next engine, but I don't want to go into any kind of big bucks on exotic performance mods.  I just want a rock solid, basic engine.  I don't want to go used.  I want something with a warranty like in a reman.

I also don't want to be forced into something that uses premium fuel.

What are some of the options?
 
My LQ9 6.0 H.O. (364) engine does not "require" premium, but it wouldn't hurt it's feelings if it got some. (Which it never does.)

And isn't there an LQ4 6.0 with slightly less compression than the LQ9?

That engine would most certainly use regular gas unless it's hopped up.

The owner's manual states that premium is the preferred fuel for mine, but it can also run just fine on regular.

I ran premium when I first got the truck, but when it went over $4.00 a gallon back then, I switched to regular and since I never saw any difference in performance or MPG, I decided to stay with the cheap stuff.

The later model 6.2 engines require premium, if I am not mistaken, but that engine is not an option for you, I would think.

I'm sure the guys that are learned in tuners will tell you that you should be able to tune the engine for the grade of fuel you plan on using.

If you choose to go with maximum punch, I bet you will be looking at premium grade.

Back off the tune a tad, and a lower grade of gas should work fine.

I would imagine that either of those 6.0 engines would be a more direct "swap" into your truck than a "350".

But I could be wrong.

Wouldn't be the first time.
 
I am leaning toward an LQ9.  Seems like an ideal upgrade for my purposes.

I understand the injectors would need to be replaced with larger ones, but all of the other 5.3 gear will carry over and bolt on.
 
That's what I thought.

Can anyone recommend some good places to get a reman 6.0?
 
Can I suggest having your current engine checked out by another mechanic?
Maybe it not somethign serious but something simple.

165K is nothing for these engines especially an 03 version unless you ran it without oil.

Unless of course you want a new engine.
 
EXT4ME said:
Perhaps Jasper Engines.

I hear good things about them.

I had tried going to find an engine on Jasper's website a few days ago.  There was no option for the 6.0 for a 1500 Av.  So I called them.  I asked them about getting a 6.0 for my Av and they said they will only sell a like engine for a vehicle as it came from the factory or if that engine was an option from the factory for that vehicle.  So I guess that ruled them out.,. . . . or they ruled themselves out.
 
ygmn said:
Can I suggest having your current engine checked out by another mechanic?
Maybe it not somethign serious but something simple.

165K is nothing for these engines especially an 03 version unless you ran it without oil.

Unless of course you want a new engine.

Good points ygmn!

I also thought 165k was way too soon for this engine to have problems.  That said, when I was going to another mechanic, I started having doubts about that shop's diligence in doing work.  They seemed scatter brained.  So I made up my mind the last time I would use them was for an oil change.  This was around 85,000 miles.  After I got my Av back from them, the engine was making ticking noises.  My thought was during the oil change, they drained the oil, got distracted, forgot they didn't put new oil in, and then started the engine, causing damage.  I cannot prove this, nor can I accuse them of doing this, but I really had such a strong sense that this is what happened.  The engine was never the same since then.

I was thinking about having someone get into the engine and just determine, but not necessarily fix, the problem (unless it was cheap).  I really do not want to buy another engine at this point.  Money is tight and debts are high from being out of work last year.
 
As the car talk guys say...

Go to auto parts store and buy the oil additive products that have MIRACLE or LIFE GIVING etc in the title and add it to crankcase.

are you burning oil?
MPG seem worse?
Any check engine light?

 
ygmn said:
As the car talk guys say...

Go to auto parts store and buy the oil additive products that have MIRACLE or LIFE GIVING etc in the title and add it to crankcase.

are you burning oil?
MPG seem worse?
Any check engine light?

I have already been using SPECIAL. . and . . . MAGIC sauce in my engine. . . Z Max.  It worked for about a month.  Put some in again and it didn't help at all.

I do miss Click and Clack. . The Tappet Brothers.  Too bad the one brother got Alzheimer's and died.  Great show, still playing in reruns.


I've been burning a quart of oil a month for about six months.  That increased to about a quart every two weeks.  After I added the SPECIAL MAGIC Z Max sauce, it went back down to a quart a month.

MPG has declined over the past two years to 12-15mpg.

The check engine light has been coming on intermittently.  It sometimes comes on when first starting, but then the engine smooths out and the light goes off.  The mechanic thought it was an intermittent problem with one of the coils.  It usually never happens when I'm at their shop.  So they said to leave the Av with them and they'd test it out on an early morning start to try to pin down the problem.  It's difficult for me to leave my Av with them, as transportation is a problem.  I either have to take an expensive cab ride to get back home or I have to rent a car.
 
If money is tight why not a reman Jasper 5.3?

If you go to the 6.0 as you noted you are going to need new injectors, and with new injectors a custom computer tune.  I put it an ATK 460hp 6.0 but I do my own custom tuning.
 
If you have the tool - I suggest doing at least a compression test.

and get the code read at auto parts store.....

Might only need something as simple as lifter, valve guides, PCV or timing chain, HEad rebuild etc.
Something that costs way less then replacement and you still can get another 200K out of her.


For me if I was in your shoes I would spend a couple of hundred bucks to find out actual problem and see if it can be repaired by going to a good engine man....

Good luck
 
If you do go with a different motor another option is a junkyard engine. The Av's did not come with 6.0's but it is an option in other GM trucks.

If you go with a junkyard engine you can ask for a turnkey engine. That would come with the harness, computer and all connected items such as injectors etc.  Still probably talking $1000 or more and junk yards only generally give 30 day warranties on the engines but is another option as well. I bought a low mileage engine for a car I have and it came with all the accessories, the wire harness, computer etc...

 
redheadedrod said:
If you do go with a different motor another option is a junkyard engine. The Av's did not come with 6.0's but it is an option in other GM trucks.

If you go with a junkyard engine you can ask for a turnkey engine. That would come with the harness, computer and all connected items such as injectors etc.  Still probably talking $1000 or more and junk yards only generally give 30 day warranties on the engines but is another option as well. I bought a low mileage engine for a car I have and it came with all the accessories, the wire harness, computer etc...

Ditto.  If money is tight, this is the way to go.  There are a lot of low mileage 6.0s out there and you can get the complete engine for a little over $1000 with a warranty.  That way you can pick and choose which items to swap out and you will have a bunch of spares you can keep or sell.  I am looking to do this maybe next year when I start towing a travel trailer regularly.
 
Yup, the way I will do it too when it comes time... If done on MY time I expect to get a 6.0 and drop it off at a performance shop with the computer and have them build it up and reprogram the computer. I COULD get an HP tuner and do it myself but by the time I buy the tuner and the manual to learn how to do it myself I am at $1000 and don't yet have the experience to do it right.

Rodney
 
redheadedrod said:
If you do go with a different motor another option is a junkyard engine. The Av's did not come with 6.0's but it is an option in other GM trucks.

If you go with a junkyard engine you can ask for a turnkey engine. That would come with the harness, computer and all connected items such as injectors etc.  Still probably talking $1000 or more and junk yards only generally give 30 day warranties on the engines but is another option as well. I bought a low mileage engine for a car I have and it came with all the accessories, the wire harness, computer etc...
The 6.0 was an option for a few years in the Avy. I believe '09 was a year where you could get the 6.0 and 4.10 gears together.
 
When you get into 2nd gen you have the AFM                                                                                                                                                            [Active Fuel Management].
 
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