Replacing my 5.3L, what to look for?

subssonic

subssonic

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[SIZE=10.5pt]Hello I have a 2006 GMC Envoy Denali that is in need of a replacement motor. Is there a certain type of 5.3 I need to buy? If I recall, my motor has the displacement on demand feature. I'm just a little confused because it looks like there are several types of 5.3's. ANY help would be much appreciated!!![/SIZE]


Thanks,
David
 
Will the heads be fine? Are all 5.3L blocks the same, just the heads different?
 
BlazingTrails said:
Looking over the other thread it sounds like you may have spun a bearing. Or possibly had a cam lock up. Did you ever pull the heads? I am at work, so I didn't have time to read the whole thread...
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No I haven't taken anything off/out of the suv
 
You really need to get it apart. It goes quickly if it is on a stand. At that point you can check the heads, see if they are good. If not then you will need a long block. You have a bunch of options really depending on what you want to spend if you want to change anything etc. But really it comes down to the same motor you have in there now and the L33 which has not Displacement on Demand. Time to get things apart and just look at it. Check out car-part.com though. Some good deals on motors on there. Are you planning to do this yourself or take it somewhere?
 
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sarg said:
You really need to get it apart. It goes quickly if it is on a stand. At that point you can check the heads, see if they are good. If not then you will need a long block. You have a bunch of options really depending on what you want to spend if you want to change anything etc. But really it comes down to the same motor you have in there now and the L33 which has not Displacement on Demand. Time to get things apart and just look at it. Check out car-part.com though. Some good deals on motors on there. Are you planning to do this yourself or take it somewhere?
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I was planning to pull the motor myself, but I'm not so sure anymore. It looks REALLY crammed in there.
 
You have a 2WD which makes it a lot easier to pull the motor, so at least you have that going for you. Get quotes on rebuilt motors, short and long blocks, GM crate motors and good low mileage used ones from a salvage yard. Depending on your budget, skill set and shape of the exterior, pick the option that best suits you. I see that you are in Florida, I winter in Fort Myers and I bought a 2006 Saab 9-7x that looks brand new underneath. I would assume that yours would be the same and will give many more years and miles of use. If possible, I think I would do without the DOD option.

Doug
 
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ddgm said:
You have a 2WD which makes it a lot easier to pull the motor, so at least you have that going for you. Get quotes on rebuilt motors, short and long blocks, GM crate motors and good low mileage used ones from a salvage yard. Depending on your budget, skill set and shape of the exterior, pick the option that best suits you. I see that you are in Florida, I winter in Fort Myers and I bought a 2006 Saab 9-7x that looks brand new underneath. I would assume that yours would be the same and will give many more years and miles of use. If possible, I think I would do without the DOD option.

Doug
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So I'm seeing quite a few people say the same thing about deleting the DOD option. What is the advantage with doing that? Seeing that this is my daily and my only concern is reliability and not too bad mpg.
 
[SIZE=medium]I briefly looked but does anyone have a write up on removing the engine. Like tricks of the trade and things to watch out for? Should I pull the tranny with the motor?[/SIZE]
 
subssonic said:
So I'm seeing quite a few people say the same thing about deleting the DOD option. What is the advantage with doing that? Seeing that this is my daily and my only concern is reliability and not too bad mpg.
Click to expand...
DOD is supposed to improve fuel mileage (decrease consumption). I have not found that to be the case since I had mine turned off via a tune. My around town normal driving is netting me about 13.8 mpg, which is what I had before DOD turn off. Most folks that disable it (via a tune or using the Range device) report equal if not greater mpg.

What it does do in a large number of engines, however, is contribute to oil consumption. The rings on the DOD cylinders get stuck and allow oil to blow by into the combustion chamber. The early fixes were to replace the driver's side valve cover (PCV issue), add a windage plate/tray to the crankcase to prevent oil slinging, and as last resorts, re-ring the pistons and hone the cylinder walls. None of those work. I found a truck forum and the stories there were awful. I haven't read about many DOD related engine failures here, but on that forum, there were quite a few. It seems as though we got the best transition into/out of DOD - I couldn't feel or hear it (save for a little ticking when driving by a curb or building), but those folks were talking of hearing (exhaust) and feeling the transition.

Anyway, I'll see if my engine can recover from the exceptionally high oil usage. If not, I'll contemplate a rebuild with non-DOD parts.
 
subssonic said:
[SIZE=medium]I briefly looked but does anyone have a write up on removing the engine. Like tricks of the trade and things to watch out for? Should I pull the tranny with the motor?[/SIZE]
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Spend the few bucks on a Haynes manual and see what they say. I can scan a few pages from mine if you want to get a quick idea of how it says to do it.

As far as puling the tranny with the motor, I have done it both ways. I guess it depends on what the final outcome is to be. If you are not replacing the tranny, leave it in there. Some of the bellhousing bolts may be hard to get to, and that may cause some folks to pull them together and separate them once they are out of the vehicle.
 
Pulling the motor and trans is probably easier really when it comes time to put it back in. Getting it out is a bit harder but not much really. Just pull the driveshaft and disconnect the tranny lines.

Best advice is pull the radiator, ac condensor and everything up front first or you may be replacing those too, haha. Remove and label every bolt in baggies as you go. Lastly clean everything while it is out. Much easier.
 
i unbolt the power steering pump and leave it zip-tied to the frame. Saves from having to deal with the fluids. I try and remove as much as i can on the car. remove intake manifold, optionally coil pack brackets to clear the cowl. you can leave the exhaust manifold on if its stock (LTs are a no-go)

if you're pulling the trans along with you need to remove the steering crossmember. you can unclp the harness from left to right and leave it in the car, or take apart the fuse box and leave it on the engine


20140520_204317.jpg
 
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I just finished replacing my 5.3 in an 06 Denali. It was a pretty big job due to the fact that the front axle runs through the bottom of the motor so the front end had to be taken apart to get motor out. The motor mount bolts are almost impoosible to get out without romoving struts as well. When you remove the starter, the hole will allow you to get to all converter bolts to remove tranny from motor. The easiest way to get top two bell housing bolts is to remove throttle body. That also makes plenty of space for motor to come and go. Helps with wire harness connections to tranny too. You will need to remove radiator, a/c condenser, air filter box/wiper fluid reservoir, all front bumper components, grill, headlights, etc. everything up from and it opens up nicely to give you plenty of space. I left my power steering pump dangling there which turned out to be a pain but was manageable. Well if you have any other questions I'll keep an eye on thread....
 
The motor in your vehicle is all aluminum and was very hard for me to find. Its gonna need to be out of another Denali preferably same year to avoid any issues. I bought mine used with about 100k miles from bill smith auto parts in Illinois out of a wrecked one and they had two so worth a shot. They crated it and shipped it to Florida for me where it then came to me by boat in the virgin islands. All cost me about 2500 door to door...I'm still trying to figure out a misfire problem which is probably a sensor but everything else was fine. Anyway I hope this helps...
 
Welcome to the nation. Does the Tx in your handle reference Texas?
Did your 5.3 have the DOD system? Was that part of the problem?
I have been to St Croix a few times for projects at Hess Oil refinery.
I think that it may now be shut down or sold. I am retired and not up
to date on the industry.
 
Hello and yes it is for TX. I'm on STJ but moving back soon for a new job. Rod bearing went and nothing on island to try and repair that so I just bought a used motor..I am not sure what the dod system is but I'm not sure if I have it on vehicle? I basically just decided to swap motors myself and am no regular mechanic but do all my own repairs if possible so I know my way around a vehicle. Computers and sensors are usually where I need all the help. I am having a random misfire issue now but other than that it all went pretty well....
 
DoD is Displacement on demand. It was GM's failed attempt to get better gas mileage, etc. Probably trying to comply with some governmental regulation, but what it does is cuts out fuel to various cylinders when cruising. The bad part is that this seems to lead to excessive wear on those cylinders and a lot of time more oil consumption. There are two ways of getting around this. One is to disable it in the tune, which is what I did. The second, what I plan to do eventually, is replace the lifters, springs and cam along with the valley cover with those from a non-DoD truck. This would also be a great time to put in a new bump stick! These motors really do wake up with a little better cam. The 2006+ had DoD in the 5.3 motors. What year was the motor they shipped out to you?
 
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It was an 06 so it must have it? I have the old motor here as well with a lot of good parts on it so I have been swapping out little things because it came with harness, throttle body, injectors, pretty much everything except bolt on components...I can't seem to figure out a random misfire code it is giving though....been a real pain!!
 
Have you tried disconnecting the coil connector one at a time until you get a cylinder with no change? Did you use new plugs?
 
2005 had DOD because mine did. Tune took care of that.
 
TxMav, have you thought about the injectors? Do you know which cylinder is misfiring? If it isn't the plugs or coils, what about a plug wire?
 
Yea I changed those as well I'm starting to wonder if it is a vacuum leak under throttle body? Thanks though...
 
You know it's strange because it will run fine for a bit but then starts idling rough and about very couple minutes it straightens up only to gradually start idling rough again and so on?? It's like it comes and goes?
 
did you use the computer the "new engine to you" came with? Could your problem be the DOD feature kicking in and out.... wiggle your coil harness connector at every coil and see if anything happens...
 
Knblazer I am not using the new motors computer. Mine was fine so that didn't even cross my mind. Everything was just plug and play I thought? I have gone through the coils but I am going to check them all again and really listen/look for differences in all. If dod is the case, what would my next step be?
 
Not sure if this is related but another thing is my a/c compressor will not engage. I have jumped connectors and still won't kick on. However I jumped it at relay and it comes on so wiring and connections are good but for some reason I guess computer is shutting it down? Just curious if that could be related? Anyway thanks
 
couldn't hurt to run the old computer before you end up pulling your hair out..:p
on the DOD, I have no clue...
 
I had this motor shipped from Illinois to me in the US Virgin Islands so I guess I need to contact seller and see if it is still around? That could be tricky......thanks again
 
TxMaverick75 said:
I had this motor shipped from Illinois to me in the US Virgin Islands so I guess I need to contact seller and see if it is still around? That could be tricky......thanks again
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oh, I thought it came with it...hmm sensors you replaced, were they AcDelco?
 
something else you could do is getting a scanner that can give you misfire counts....
 
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